Patent Publication Number: US-2019179314-A1

Title: Vehicle inspection system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/949,375, filed 10 Apr. 2018, which claims priority to U.S. Provisional Application No. 62/491,840, filed 28 Apr. 2017. The entire disclosures of these patent applications are incorporated herein by reference. 
    
    
     FIELD 
     The inventive subject matter described herein relates to inspecting vehicle systems. 
     BACKGROUND 
     Maintaining the health of a vehicle is important to the safety and longevity of a vehicle. Routine maintenance is performed to ensure that components and systems of the vehicles are functioning properly. Over time, vehicle systems and components may become damaged and/or fail. Some vehicles may respond to failure by stopping movement of the vehicle, not performing at peak performance, or the like. Alternatively, damaged and/or failed vehicle systems and components may lead to catastrophic results leading to significant financial losses, loss of life, or the like. 
     The vehicles may be manually inspected to diagnose the health of the vehicle and to maintain the health of the vehicle systems and components. When inspected, either for routine maintenance or as a result of a failure, vehicles may be taken to a repair center where a maintenance operator is provided a given set of troubleshooting instructions. These instructions can take a significant amount of time to complete with many tasks and steps to complete. Additionally, some tasks are difficult for the maintenance operator to execute because they require additional measurement equipment, are tedious to perform (e.g., if a specific execution sequence is essential), or may place the maintenance operator at an elevated risk (e.g., taking engine measurements near the engine while the engine is operating). 
     BRIEF DESCRIPTION 
     In one embodiment, an inspection system includes one or more sensors that are selectively coupled to a vehicle during one or more of an inspection event or a maintenance event for the vehicle and a controller that is operable to cause a control system of the vehicle that controls plural operations of the vehicle to initiate a first operation and a different, second operation of the plural operations of the vehicle. The controller is configured to determine whether the control system of the vehicle has first sensor information indicative of a state of the vehicle during the first operation of the vehicle. The controller is configured to send a command signal to the control system of the vehicle in order to direct the control system of the vehicle to change vehicle operations from the first operation to the second operation of the vehicle responsive to determining that the control system lacks the first sensor information that was requested. The controller obtains second sensor information from the one or more sensors based on the second operation of the vehicle and determines a condition of one or more components of the vehicle based on the first sensor information and the second sensor information. 
     In one embodiment, a method includes selectively coupling one or more sensors of an inspection system to a vehicle during one or more of an inspection event or a maintenance event for the vehicle. The method includes operably coupling a controller with the one or more sensors of the inspection system wherein the controller is operable to cause a control system of the vehicle to initiate a first operation of the vehicle and a different, second operation of the vehicle. During the first operation of the vehicle it is determined whether the control system of the vehicle has first sensor information indicative of a state of the vehicle. Responsive to determining that the control system lacks the first sensor information, the controller sends a command signal to the control system of the vehicle in order to direct the control system of the vehicle to change vehicle operations from the first operation to the second operation of the vehicle. Second sensor information is obtained from the one or more sensors based on the second operations of the vehicle. A condition of one or more components of the vehicle is determined based on the first sensor information and the second sensor information. 
     In one embodiment, a system includes a first sensor configured to determine an operating characteristic of a vehicle and a second sensor configured to determine one or more of an externality characteristic of the first sensor or an externality characteristic of the vehicle. The externality characteristic of the first sensor is representative of one or more external conditions to which the first sensor is exposed. The externality characteristic of the vehicle is representative of one or more external conditions to which the vehicle is exposed. The system includes a controller configured to diagnose an operational state of the vehicle based on the operating characteristic of the vehicle and based on the one or more of the externality characteristic of the first sensor or the externality characteristic of the vehicle 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Reference is now made briefly to the accompanying drawings, in which: 
         FIG. 1  illustrates a schematic illustration of an inspection system of a vehicle system in accordance with one embodiment; 
         FIG. 2  illustrates a schematic illustration of an onboard control system for a propulsion-generating vehicle in accordance with one embodiment; 
         FIG. 3  illustrates a schematic illustration of a controller in accordance with one embodiment; 
         FIG. 4  illustrates a schematic illustration of a sensor system in accordance with one embodiment; 
         FIG. 5  illustrates an exploded illustration of the sensor system of  FIG. 4  in accordance with one embodiment; and 
         FIG. 6  illustrates a flowchart of a method for determining a fault state of a vehicle in accordance with one embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     One or more embodiments of the inventive subject matter described herein relate to systems and methods that inspect a vehicle in order to diagnose a condition and the health of the vehicle. The systems and methods include a controller that is transferably coupled with a control system onboard the vehicle that controls operation of the vehicle. For example, the controller may be transferred between off-board and onboard the vehicle, wherein the controller is coupled with the control system when the controller is transferred onboard the vehicle. One or more processors of the controller may determine whether the control system has sensor information indicative of a state of the vehicle. Optionally, one or more sensor systems coupled with the controller, coupled with the control system, coupled with the vehicle, or the like, may have sensor information of the control system. 
     Responsive to determining that the control system lacks the sensor information, the one or more processors send a command signal to the control system instructing the control system of the vehicle to perform one or more operations. For example, the command signal instructs the control system to perform one or more operations in order for the controller to obtain sensor information based on the performance of operations by the vehicle. Using the sensor information and/or the status data obtained by the performance of operations by the vehicle, the one or more processors of the controller determines a condition of the vehicle. For example, the controller may autonomously and/or semi-autonomously determine an operational state, a fault state, a damaged state, or the like, of one or more components of the vehicle. 
     In one or more embodiments, the systems and methods include a first sensor system and a second sensor system. The first and second sensor systems may be operably coupled with one or more of the control system of the vehicle or with the controller. The first sensor system is configured to determine an operating characteristic of the vehicle, and second sensor system is configured to determine an externality characteristic of the first sensor system or an externality characteristic of the vehicle. For example, the externality characteristic of the first sensor system may represent an external condition to which the first sensor system is exposed to. The externality characteristic of the vehicle may represent an external condition to which the vehicle is exposed to. Using the operating characteristic of the vehicle determined by the first sensor system, the externality characteristic of the first sensor system determined by the second sensor system, the externality characteristic of the vehicle determined by the second sensor system, or any combination therein, the controller diagnoses an operational state of the vehicle. For example, the controller may autonomously and/or semi-autonomously diagnose an operational state, a fault state, a damaged state, a health score, or the like, of one or more components and or one or more systems of the vehicle. 
     This subject matter may be used in connection with rail vehicles and rail vehicle systems, or alternatively may be used with other types of vehicles. For example, the subject matter described herein may be used in connection with automobiles, trucks, mining vehicles, other off-highway vehicles (e.g., vehicles that are not designed or are not legally permitted for travel on public roadways), aerial vehicles (e.g., fixed wing aircraft, drones or other unmanned aircraft, or the like), or marine vessels. 
     The vehicle system can include two or more vehicles mechanically coupled with each other to travel along a route together. Optionally, the vehicle system can include two or more vehicles that are not mechanically coupled with each other, but that travel along a route together. For example, two or more automobiles may wirelessly communicate with each other as the vehicles travel along the route together as a vehicle system to coordinate movements with each other. Optionally, a vehicle system or consist may be formed from a single vehicle. 
       FIG. 1  illustrates one embodiment of an inspection system  100  used to determine a condition of one or more vehicles  106  of a vehicle system  102 . The illustrated vehicle system  102  includes propulsion-generating vehicles  106 A,  106 B that travel together along a route  114 . Although the vehicles  106  are shown as being mechanically coupled with each other, optionally the vehicles may not be mechanically coupled with each other. Instead, the vehicles can communicate with each other (while remaining mechanically separate) in order to coordinate the movements of the vehicles with each other so the vehicles travel together along the routes. 
     The propulsion-generating vehicles  106 A,  106 B are shown as locomotives and the vehicle system  102  is shown as a train in the illustrated embodiment. Alternatively, the vehicles  106  may represent other vehicles such as automobiles, rail vehicles, marine vessels, mining vehicles, aerial droves, other aerial vehicles, or the like and the vehicle system  102  can represent a grouping or coupling of these vehicles. The number and arrangement of the vehicles  106  in the vehicle system  102  is provided as one example and is not intended as a limitation on all embodiments of the subject matter described herein. 
     The propulsion-generating vehicles  106  can be arranged in a distributed power (DP) arrangement. For example, the vehicle system  102  can include a first vehicle  106 A that issues control signals to a second vehicle  106 B. The designations “first” and “second” are not intended to denote spatial locations of the propulsion-generating vehicles  106  in the vehicle system  102 , but instead are used to indicate which propulsion-generating vehicle  106  is communicating (e.g., transmitting, broadcasting, or a combination of transmitting and broadcasting) control signals and which propulsion-generating vehicle  106  is being remotely controlled using the control signals. For example, the first vehicle  106 A may or may not be disposed at a front end of the vehicle system  102  (e.g., along a direction of travel of the vehicle system  102 ). Additionally, the remote second vehicle  106 B need not be separated from the first vehicle  106 A or may be separated from the first vehicle  106 A by one or more other propulsion-generating vehicles  106  and/or non-propulsion-generating vehicles. 
     The control signals issues by the first vehicle  106 A to the second vehicle  106 B may include directives that direct operations of the remote second vehicle  106 B. These directives can include propulsion commands that direct propulsion subsystems of the second vehicle  106 B to move at a designated speed and/or power level, brake commands that direct the second vehicle to apply brakes at a designated level, and/or other commands, or the like. The first vehicle  106 A issues the control signals to coordinate the tractive efforts and/or braking efforts provided by the propulsion-generating vehicle  106 B in order to propel the vehicle system  102  along the route  114 , such as a track, road, waterway, or the like. 
     The control signals can be communicated using a communication system  116 . In one or more embodiment, the control signals are wirelessly communicated using the communication system  116 . The communication system  116  may include one or more components onboard the propulsion-generating vehicles  106  that are used to establish a communication link  112  between the vehicles  106  in the vehicle system  102 . 
     The communication system  116  may include wireless transceiving hardware and circuitry (e.g., antennas  110 ) disposed onboard the propulsion-generating vehicles  106 . For example, the second vehicle  106 B may be remotely controlled by the first vehicle  106 A by the communication link  112  established between the first and second vehicles  106 A,  106 B. Additionally or alternatively, the propulsion-generating vehicles  106  may be communicatively linked through a wired connection between one or more of the propulsion-generating vehicles  106  or non-propulsion-generating vehicles. 
     The propulsion-generating vehicles  106 A,  106 B each include a control system  108  disposed onboard the vehicles  106 . The control system  108  can include hardware circuits or circuitry that include and/or are connected with one or more processors that perform the operations described herein in connection with the control system  108 . The control system  108  can control or limit movement of the vehicles  106  and/or the vehicle system  102  based on one or more limitations. For example, the control system  108  can prevent the vehicles  106  from entering a restricted area, can prevent the vehicles  106  from exiting a designated area, can prevent the vehicles  106  from traveling at a speed that exceeds an upper speed limit, can prevent the vehicles from traveling at a speed less than a lower speed limit, can instruct the vehicles  106  to travel according to a designated trip plan generated by an energy management system, can control one or more of a throttle setting, brake setting, speed setting, radiator fan speed, pump speed, coolant flow rate, or the like of the vehicles. For example, the control system  108  may monitor and/or control operations of a cooling system of the vehicles such as increase, decrease, stop, limit, or the like, the amount of coolant (e.g., air or liquid coolant) that flows through the cooling system of the vehicle  106 . The control system  108  will be discussed in more detail below with  FIG. 2 . 
     The inspection system  100  includes a controller  104  that is transferably coupled with the control system  108  of one or more of the vehicles  106 . For example, the controller  104  may be coupled with (e.g., connected to, plugged into) the control system  108  of the first vehicle  106 A, subsequently uncoupled with (e.g., disconnected, unplugged) the control system  108  of the first vehicle  106 A, and then subsequently coupled with (e.g., connected to, plugged into) one or more of the control system  108  of the second vehicle  106 B, an alternative vehicle system, or the like. The controller  104  is off-board the vehicle system  102  during movement of the vehicle system  102 . For example, the controller  104  is off-board the vehicle  106  and/or the vehicle system  102  when the vehicle system  102  is traveling along the route  114  from a first location to a different, second location (e.g., during typical transit of the vehicle system  102 ). Alternatively, the controller  104  is transferred to be onboard the vehicle  106  and/or vehicle system  102  during alternative movement of the vehicle system  102 . For example, the controller  104  may be transferred from off-board the vehicle  106  to onboard the vehicle  106  when the vehicle  106  or vehicle system  102  has slowed, has come to a stop, has been forced to a stop due to a fault of the vehicle, or the like. For example, the controller  104  may be transferred to be onboard the vehicle  106  at a vehicle repair center, or the like. 
     The controller  104  is operably coupled with the control system  108  for an inspection event or a maintenance event for the one or more vehicles  106  of the vehicle system  102 . The inspection event may include inspection of one or more components of the vehicle  106  (e.g., radiator fans, pumps, heat exchangers, compressors, or the like), one or more systems of the vehicle  106  (braking system, cooling system, propulsion subsystem, communication systems, or the like). For example, one or more components, one or more systems, or a combination of one or more components and/or systems therein, may need to be inspected by the controller  104  of the inspection system  100  in order to determine an operational state, a fault state, a damaged state, a health score, a condition, or the like, of the components and/or systems of the vehicle system  102 . The maintenance event may include maintenance (e.g., repair, replacement, or the like) of a component of the vehicle  106  and/or of a system of the vehicle  106 . For example, one or more components, one or more systems, or a combination of one or more components and/or systems therein, may need to be repaired based on a condition of the components and/or systems determined by the controller  104 . 
     The controller  104  may communicate with the control system  108  via a wireless communication link, a wired connection, or the like, during the inspection event and/or during the maintenance event. For example, in the illustrated embodiment of  FIG. 1 , the controller  104  is disposed onboard the vehicle  106  during the inspection event, and may communicate with the control system  108  via a wired connection. Additionally or alternatively, the controller  104  may be disposed off-board the vehicle  106  during the inspection and/or maintenance event and may communicate with the control system  108  via a wireless connection. Optionally, the controller  104  may be disposed off-board the vehicle  106  during a first inspection event, and may be subsequently disposed onboard the vehicle  106  during the same, first inspection event. The controller  104  may be transferable between onboard and off-board the vehicle  106  during inspection, maintenance, or the like, of the vehicle system  102 . For example, the controller  104  may be a laptop computer, a tablet computer, or an alternative cordless device, that may be operably coupled with the control system  108  when the controller  104  is onboard the vehicle, may be operably coupled with an external sensor that is transferable between off-board and onboard the vehicle  106  (e.g., an inspection sensor system that is operably coupled to the vehicle during inspection and/or maintenance of the vehicle), or the like. Alternatively or additionally, the controller may be one or more of: handheld; portable; battery powered; powered via a removable power cord that is connectable to an external power source; both battery powered and powered via a power cord; and/or communicatively connectable to a vehicle (for transmitting and receiving signals from the vehicle) via wireless and/or wired connections, e.g., Ethernet. 
     The controller  104  controls movement of the vehicle  106  with the control system  108  during the inspection event and/or maintenance event. For example, the controller  104  may selectively over-ride, take control of, or the like, one or more settings of the control system  108  that control operations and/or movement of the vehicle  106  when the controller  104  is coupled with the control system  108 . Additionally or alternatively, the controller  104  may not control movement of the vehicle  106  with the control system  108  during the inspection event and/or maintenance event. For example, the controller  104  may inspect and/or maintain the vehicle  106  while the vehicle  106  travels along the route  114 . The controller  104  sends one or more command messages to the control system  108  in order to obtain sensor information indicative of a state of the vehicle  106  in order to determine a condition of the vehicle  106 . Additionally or alternatively, the controller  104  may be operably coupled with the control system  108  in order to control one or more operations of the vehicle  106  in order to obtain sensor information indicative of a state of the vehicle  106  in order to determine the condition of the vehicle. The controller  104  will be discussed in more detail below with  FIG. 3 . 
     The inspection system  100  includes one or more control system sensors  230  that are maintained at a position onboard the vehicle  106 . The control system sensors  230  are operably coupled with the controller  104  and/or with the control system  108 . For example, the vehicle  106  may have control system sensors that are not transferable between onboard and off-board the vehicle  106 . For example, the one or more control system sensors may be fixed onboard the vehicle  106  and sense information (e.g., monitor, gather, measure, collect, read, or the like) of systems of the vehicle (e.g., the propulsion subsystem, an energy-management system, or the like) and/or components of the vehicle during movement of the vehicle  106  (e.g., during a trip). The control system sensors  230  will be described in more detail below. 
     The inspection system  100  includes one or more external sensor systems  130  that are selectively coupled to the vehicle  106  during an inspection event and/or a maintenance event of the vehicle  106  in accordance with one embodiment. The external sensor systems  130  may sense temperature, pressure, vibrations, fluid flow rates, gas flow rates, visually inspect via a camera, audio inspect via a microphone, or the like. For example, the external sensor systems  130  may be coolant temperature sensors, manifold absolute pressure sensors, air flow meters, or the like, configured to sense (e.g., monitor, gather, measure, read, collect, or the like) information that is indicative of the state of the vehicle  106 , the state of one or more components of the vehicle, and/or the state of one or more systems or the vehicle. One example of a configuration of the external sensor systems  130  is described below with  FIGS. 4 and 5 . 
     The external sensor system  130 A may be a first external sensor system, and the external sensor system  130 B may be a second external sensor system. The designations “first” and “second” are not intended to be spatial locations of the external sensor systems  130 , but instead are used to indicate which external sensor system may have first sensor information and which external sensor system may have second sensor information. The first and/or second external sensor systems  130 A,  130 B are selectively coupled to the first and/or second vehicle  106 , to the vehicle system  102 , or any combination therein. For example, the first external sensor system  130 A may be a coolant temperature sensor. selectively coupled to the vehicle  106  at a location near the engine water inlet conduit in order to sense the coolant temperature during inspection of the vehicle cooling system. Alternatively, the first external sensor system  130 A (e.g., the coolant temperature sensor) may be selectively disconnected from the vehicle  106  if the inspection event does not include inspection of the vehicle cooling system. For example, the external sensor systems  130  may be selectively disconnected from the vehicle  106  subsequent to the inspection event and/or the maintenance event. One or more external sensor systems  130  may be transferred off-board the vehicle  106  subsequent to the inspection event, and one or more external sensor systems  130  may remain disposed onboard the vehicle  106  subsequent to the inspection event. 
     The external sensor systems  130  are transferable between onboard and off-board the vehicle  106  and are operably coupled with the controller  104  in accordance with one embodiment. The first and second external sensor systems  130 A,  130 B may be transferred between off-board and onboard the vehicle  106 , transferred between a first location and a second location onboard the vehicle  106 , transferred between the first vehicle  106 A and the second vehicle  106 B, or the like. 
     The first external sensor system  130 A may sense (e.g., monitor, gather, measure, collect, read, or the like) first sensor information (e.g., the engine oil inlet temperature) during a first operation of the vehicle  106 , and the second external sensor system  130 B may sense (e.g., monitor, gather, measure, collect, read, or the like) second sensor information (e.g., the engine water inlet temperature) during a second operation of the vehicle  106 . For example, the first external sensor system  130 A may be selectively coupled to the vehicle  106  at a first location (e.g., coupled to an engine oil inlet conduit in order to measure the temperature of the oil that is directed into the engine) during a first operation of the vehicle  106  (e.g., at an increasing speed of the vehicle), and the second external sensor  130 B may be selectively coupled to the vehicle  106  at a second location (e.g., coupled to an engine water inlet conduit in order to measure the temperature of the coolant that is directed into the engine) during a second operation of the vehicle  106  (e.g., at a decreasing speed of the vehicle) during a vehicle inspection event. 
     Optionally, the first and second external sensor systems  130  may be disposed at a same location onboard the vehicle  106  in order to sense the first sensor information during the first operation of the vehicle with the first external sensor system  130 A, and to sense the second sensor information during the second operation of the vehicle with the second external sensor system  130 B. Optionally, the first external sensor system  130 A may be selectively coupled to the vehicle, and the second external sensor system  130 B may not be selectively coupled to vehicle. 
     In the illustrated embodiment, the first and second external sensor systems  130  are disposed onboard the first vehicle  106 A. Optionally, the first external sensor system  130 A may be disposed onboard the first vehicle  106 A, and the second external sensor system  130 B may be disposed onboard the second vehicle  106 B. For example, in the distributed power arrangement, the first vehicle  106 A may instruct the second vehicle  106 B to change the brake setting. The second external sensor system  130 B may sense the second sensor information (e.g., measure the air brake pressure of the second vehicle  106 B propulsion subsystem) during operation of the vehicle system  102 . 
     In one embodiment, the first external sensor system  130 A determines an operating characteristic of the vehicle  106 . For example, the first external sensor  130 A may sense (e.g., measure, read, collect) sensor information that is indicative of how one or more components and/or one or more systems of the vehicle  106  are operating. In one example, the first external sensor system  130 A may be a pressure sensor configured to measure the air pressure of the air brake system. The first external sensor system  130 A may determine that an air compressor of the brake system is not operating to increase the pressure in the brake system within a designated time limit. In another example, the first external sensor system  130 A, selectively coupled with the vehicle  106 , may determine that a heat exchanger of the cooling system is reducing the temperature of the coolant to a designated temperature range. Optionally, the operating characteristic may be any alternative characteristic of the vehicle  106 . 
     In one embodiment, the second external sensor system  130 B determines an externality characteristic of the first external sensor system  130 A that is representative of an external condition to which the first external sensor system  130 A is exposed. The external condition may be an ambient temperature, ambient pressure, ambient humidity, or the like, of the environment to which the first external sensor system  130 A is exposed. For example, the second external sensor system  130 B may determine that the first external sensor system  130 A is exposed to a temperature that is greater than a designated threshold temperature, such as when the first external sensor system  130 A is sensing operating characteristics of a vehicle when the vehicle is located in Phoenix, Ariz. compared to when the vehicle is located in Buffalo, N.Y. Additionally or alternatively, the external condition to which the first external sensor system  130 A is exposed may be a temperature, pressure, humidity, or the like, of the vehicle  106 . For example, the first external sensor system  130 A may be operably coupled to an exhaust conduit of the engine. The second external sensor system  130 A may determine that the first external sensor system  130 A is exposed to a temperature that is greater than a designated threshold temperature, such as when the first external sensor system  130 A is operably coupled to an engine exhaust conduit compared to when the first external sensor system  130 A is operably coupled to an engine coolant input conduit. 
     Additionally, the second external sensor system  130 B determines an externality characteristic of the vehicle  106  that is representative of an external condition to which the vehicle  106  is exposed. For example, the second external sensor system  130 B may determine that the vehicle is exposed to an air pressure that is lower than a designated threshold pressure, such as when the vehicle  106  is located in Denver, Colo. compared to when the vehicle  106  is located in New Orleans, La. 
     In one embodiment, the external sensor systems  130  verify the functionality of the control system sensors  230 . For example, the external sensor systems  130  may validate the sensed information that is obtained, monitored, collected, measured, read, or the like, by the control system sensors  230 . The external sensor systems  130  may sense information that is the same, or similar to the sensed information sensed by the control system sensors  230  in order to check that the control system sensors  230  are functioning correctly, in order to check if one or more of the control system sensors  230  are not functioning correctly, or the like. 
       FIG. 2  is a schematic illustration of the control system  108  disposed onboard the vehicles  106  in accordance with one embodiment. The control system  108  controls operation of the vehicles  106 . The control system  108  can include or represent one or more hardware circuits or circuitry that include, are connected with, or that both include and are connected with one or more processors, controllers, or other hardware logic-based devices that perform the operations described herein in connection with the control system  108 . The control system  108  is connected with an input  204  and an output  206 . The control system  108  can receive manual input from an operator of the vehicle  106  through the input  204 , such as a touchscreen, keyboard, electronic mouse, microphone, throttle handle, switch, or the like. For example, the control system  108  can receive manually input changes to the tractive effort, braking effort, speed, power output, and the like, from the input  204 . For example, the control system  108  may receive a single instance of an actuation of the input  204  to initiate the established communication link  112  between the vehicles  106 A,  106 B. 
     The control system  108  can present information to the operator of the vehicles  106  using the output  206 , which can represent a display screen (e.g., touchscreen or other screen), speakers, printer, or the like. For example, the control system  108  can present the identities and statuses of the vehicles  106 A,  106 B, identities of missing vehicles (e.g., those vehicles from which the vehicle  106 A has not yet received status information), contents of one or more command messages, or the like. 
     The control system  108  is connected with a propulsion subsystem  208  of the vehicle  106 . The propulsion subsystem  208  provides tractive effort and/or braking effort of the propulsion-generating vehicles  106 . The propulsion subsystem  208  may include or represent one or more engines, motors, alternators, generators, brakes, batteries, turbines and the like, that operate to propel the vehicles  106  under the manual or autonomous control that is implemented by the control system  108 . For example, the control system  108  can generate control signals autonomously or based on manual input that is used to direct operations of the propulsion system  208 . 
     The control system  108  is connected with a communication device  210  and a memory  212  in the vehicle  106 . The memory  212  can represent an onboard device that electrically and/or magnetically stores data. For example, the memory  212  may represent a computer hard drive, random access memory, read-only memory, dynamic random access memory, an optical drive, or the like. The memory  212  stores status data of the vehicle  106  and/or the vehicle system  102  that is indicative of the state of the vehicle  106  and/or vehicle system  102  during transit of the vehicle  106  and/or vehicle system  102 . For example, the memory  212  may store data obtained from previous operations of the propulsion subsystem  208  of the vehicle  106  and/or of the propulsion subsystem  208  of each vehicle of the vehicle system  102  (e.g., data from the most recent trip, the ten most recent trips, all past trips, or the like). Additionally or alternatively, the memory may store data obtained from previous operations of individual components of the propulsion subsystem  208 , such as one or more of radiator shutter functionality, radiator cooling fan functionality, coolant flow rates, engine temperature measurements, engine water inlet temperatures, engine lube inlet temperatures, or the like. 
     The communication device  210  includes or represents hardware and/or software that is used to communicate with other vehicles in the vehicle system  102 . For example, the communication device  210  may include a transceiver and associated circuitry (e.g., antenna  110  of  FIG. 1 ) for wirelessly communicating (e.g., communicating and/or receiving) linking messages, command messages, reply messages, repeat messages, or the like. Optionally, the communication device  210  includes circuitry for communicating messages over a wired connection, such as an electric multiple unit (eMU) line of the vehicle system  102  (not shown), catenary or third rail of electrically powered vehicles, or another conductive pathway between or among the vehicles  106  of the vehicle system  102 . 
     The control system  108  is connected with an energy management system  217 . The energy management system  217  can include hardware circuits or circuitry that include and/or are connected with one or more processors that perform the operations described herein in connection with the energy management system  217 . The energy management system  217  can create a trip plan for trips of the vehicles  106  and/or the vehicle system  102  that includes the vehicles  106 . A trip plan may designate operational settings of the propulsion-generating vehicles  106  and/or the vehicle system  102  as a function of one or more of time, location, or distance along a route for a trip. Traveling according to the operational settings designated by the trip plan may reduce fuel consumed and/or emissions generated by the vehicles and/or the vehicle system  102  relative to the vehicles and/or vehicle system traveling according to other operational settings that are not designated by the trip plan. The identities of the vehicles in the vehicle system  102  may be known to the energy management system  217  so that the energy management system  217  can determine what operational settings to designate for a trip plan to achieve a goal of reducing fuel consumed and/or emissions generated by the vehicle system  102  during the trip. 
     The control system  108  includes the one or more control system sensors  230 . The control system sensors  230  sense temperature, pressure, vibrations, fluid flow rates, gas flow rates, visually inspect via a camera, audio inspect via a microphone, or the like, of one or more components and/or systems of the vehicle  106 . For example, the control system sensors  230  may be coolant temperature sensors, manifold absolute pressure sensors, air flow meters, or any alternative sensors. The control system sensors  230  are operably coupled with one or more components and/or systems of the vehicle  106  in order to sense information indicative of the components and/or systems during movement of the vehicle (e.g., during a trip). Additionally, the control system sensors  230  are operably coupled with the controller  104  during the inspection event and/or the maintenance event of the vehicle  106 . For example, the controller  104  may obtain sensor information from the control system sensors  230  during an inspection event of the vehicle. 
       FIG. 3  illustrates a schematic illustration of the controller  104  in accordance with one embodiment. The controller  104  is transferable between off-board and onboard the vehicle  106 . The controller  104  may be onboard and/or off-board the vehicle  106  and/or the vehicle system  102  and is operably coupled with the control system  108  of the vehicle  106 . For example, the controller  104  may be wirelessly connected to the control system  108 , mechanically coupled via an Ethernet cable, or the like. The controller  104  represents hardware circuitry that includes and/or is connected with one or more processors (e.g., microprocessors, controllers, field programmable gate arrays, integrated circuits, or the like) that perform the operations described herein in connection with the controller  104 . The method of operation of the controller  104  will be discussed in more detail below with  FIG. 6 . 
     The controller  104  generates command signals that are communicated by a communication unit  302 . The command signals control operations of the vehicle  106 . For example, the command signals instruct the control system  108  to initiate one or more operations of the vehicle during inspection and/or maintenance of the vehicle  106 . The communication unit  302  can send and/or receive communication signals with the vehicle  106  by a communication link  120  between the control system  108  and the controller  104 . The controller  104  receives one or more of status data, sensor information, image data, or the like, that is stored by the memory  212  of the control system  108 . For example, the controller  104  may receive status and/or sensor information that is indicative of the current state of the vehicle  106 , that is indicative of the state of the vehicle  106  during a previous operation (e.g., a past trip), that is indicative of the state of components and/or systems of the vehicle  106  during an instructed operation of the vehicle  106 , or the like. 
     In one or more embodiments, the controller  104  may control the communication device  210  of the control system  108  by activating the communication device  210 . The control system  108  examines the messages that are received by the communication device  210 . For example, the control system  108  of the vehicle  106  can examine received command messages to determine if the directives have been sent by the controller  104 , sent from one or more additional vehicles of the vehicle system  102 , or from any other system. The control system  108  implements the directive by creating control signals that are communicated to one or more systems of the vehicle  106  and/or one or more systems of the vehicle system  102  for autonomous control and/or implementation of the directive. For example, the braking system of the vehicle system  102  may need to be inspected. The controller  104  may communicate a directive that instructs the control system  108  of the first vehicle  106 A to increase the throttle setting of the propulsion subsystem of the first vehicle  106 , and subsequently communicate a second directive to the control system  108  instructing the system  102  to increase a brake setting of the system  102  in order for the braking system, and components associated with the braking system, to be inspected. Optionally, the controller  104  may communicate directives to the control system  108  to simulate operating conditions of the vehicle  106  in order to inspect, maintain, or determine a condition of any alternative system, any subsystem of a vehicle system  102 , any components of the vehicle  106 , or the like. Optionally, the controller  104  may communicate directives to the control system  108  of the first vehicle  106  to simulate operating conditions of the second vehicle  106 B in the distributed power arrangement. 
     The controller  104  can include one or more input devices  306  and/or output devices  308  such as a keyboard, an electronic mouse, stylus, microphone, touch pad, or the like. The input and/or output devices  306 ,  308  are used to communicate command signals to the control system  108 . Additionally or alternatively, the input and/or output devices  306 ,  308  may be used to communicate signals with an alternative vehicle system, a repair center, a dispatch center, or the like. 
     The controller  104  can include one or more displays  304  such as a touchscreen, display screen, electronic display, or the like. The displays may visually, graphically, statistically, or the like, display information to the operator of the controller  104 . In one example, the displays  304  may provide instructions to one or more operators of the controller  104  and/or one or more operators of the vehicle  106  that instruct the operators how to inspect or maintain the vehicle  106 . For example, the instructions may communicate to the operator a task to perform (e.g., measure the water pressure of the cooling system), when to perform the task (e.g., after the propulsion subsystem has reached a designated speed), how to perform the task (e.g., read measurements from the first external sensor system  130 A), or the like, in order to determine a condition of the vehicle  106  (e.g., a condition of the cooling system, a condition of components of the cooling system, or the like). Additionally or alternatively, the controller  104  may autonomously and/or semi-autonomously (e.g., without operator input) determine a condition of a system of the vehicle (e.g., the condition of the cooling system of the vehicle), a condition of a component of the vehicle (e.g., a heat exchanger of the cooling system), or the like. 
     The controller  104  is operably connected with components and/or systems of the vehicle system  102 . Additionally or alternatively, the controller  104  may be operably connected with components or alternative systems onboard and/or off-board the vehicle system  102 . For example, the controller  104  may be wirelessly connected with a vehicle repair center in order to autonomously locate a spare part to replace a faulty component of the vehicle  106 , create a work order to have the faulty component replaced, update a status of the vehicle  106  indicating to an operator of one or more systems that the vehicle  106  needs repair, or the like. 
     The controller  104  can include a power unit  310 . The power unit  310  powers the controller  104 . For example, the power unit may be a battery and/or circuitry that supplies electrical current to power other components of the controller  104 . Additionally or alternatively, the power unit  310  may provide electrical power to one or more other systems. 
     The controller  104  includes a vehicle selector  320 . The operator of the controller  104  can activate the vehicle selector  320  in order to select the vehicle of the vehicle system  102  from which the controller  104  would like to obtain sensor information from. For example, the controller  104  may be operably coupled with the control system  108  onboard the first vehicle  106 A, however the operator of the controller  104  may want to obtain status data from the second vehicle  106 B. The operator of the controller  104  may select the second vehicle  106 B, or one or more additional vehicles of the vehicle system  102  using the vehicle selector  320 . For example, the command signal communicated by the controller  104  may instruct the control system  108  onboard the first vehicle  106 A to request status data from the memory  212  of the second vehicle  106 B (e.g., via the communication link  112 ) in order to receive the status data of the second vehicle  106 B at the control system  108  of the first vehicle  106 A and communicate the received status data to the controller  104  (e.g., via the distributed power arrangement communication link  120 ). 
     The controller  104  is connected with a memory  326 . The memory  326  can represent a device that electrically and/or magnetically stores data. For example, the memory  212  may represent a computer hard drive, random access memory, read-only memory, dynamic random access memory, an optical drive, or the like. The memory  326  stores status data indicative of the state of the vehicle or vehicle system that is obtained by the controller  104 . For example, the memory  326  may store data indicating a determined condition of the vehicle, condition of one or more systems of the vehicle, condition or one or more components of the vehicle, or the like. For example, the memory  326  may store the sensor information related to a damaged component in order for an operator to better understand how, why, or when the component was damaged. Additionally or alternatively, the controller  104  may transfer data between the memory  326  and an alternative database outside of the controller  104 . For example, the controller  104  may wirelessly transfer data via the communication unit  302  from the memory  326  to a server and/or database at a location away from the vehicle  106 . 
     The controller  104  also includes a primary device  322  and a secondary device  324 . The primary device  322  can include hardware circuits or circuitry and/or software that includes and/or are connected with one or more processors that perform the operations described herein in connection with the primary device  322 . The primary device  322  can read the sensor information indicative of the state of the vehicle. For example, the primary device  322  may be a first data acquisition device and may receive the sensor information of the vehicle  106  from the memory  212  onboard the vehicle  106 , where the sensor information is indicative of the state of the vehicle  106 , the state of the systems of the vehicle  106 , the state of components of the systems of the vehicle  106 , or the like. The state of the vehicle may indicate how the vehicle is performing, the health of the vehicle, usage of components and/or systems of the vehicle, or the like. For example, the sensor information may indicate that a radiator shutter is malfunctioning, that the engine oil inlet temperature is outside of a designated threshold temperature, that the coolant fluid volume is outside of a designated threshold volume, or the like. The sensor information may be first sensor information that is obtained from the external sensor systems  130 , the control system sensors  230 , or the like, during a first operation of the vehicle  106 , wherein the first operation of the vehicle  106  is initiated by the controller  104  during the inspection event and/or maintenance event of the vehicle  106 . Additionally or alternatively, the sensor information may be first sensor information that is obtained from the memory  212  that is stored from previous movement of the vehicle (e.g., a previous trip, previous inspection event, previous maintenance event, or the like). 
     As one example, the primary device  322  can request temperature measurements of a coolant in a cooling system to determine if a heat exchanger of the cooling system is reducing the temperature of the coolant or if the heat exchanger is not reducing the temperature of the coolant. As another example, the primary device  322  can request pressure measurements of an air brake system to determine whether an air compressor of the brake system is operating to increase the pressure in the brake system within an upper time limit. As another example, the primary device  322  can request pressure measurements of a pump within the cooling system of the vehicle to determine if the pressure of coolant that is going into and/or out of the pump is within a designated range. 
     If the sensor information from the vehicle  106  is incomplete, or if the controller  104  is unable to accurately, or within a predetermined threshold, determine the condition of the vehicle  106 , the controller  104  may rely on the secondary device  324  in order to accurately, or within a certain threshold, determine the condition of the vehicle  106 . For example, if the first sensor information does not allow the controller  104  to determine the condition of the vehicle (e.g., condition of the vehicle, systems, components, or the like), the controller  104  directs the control system  108  to change operations from a first operation to a different, second operation of the vehicle  106  by sending a command signal to the control system  108 . 
     The secondary device  324  can include hardware circuits or circuitry and/or software that includes and/or are connected with one or more processors that perform the operations described herein in connection with the secondary device  324 . The secondary device  324  can generate the command signals that are communicated to the control system  108  that direct the control system  108  to perform the one or more different, second operations of the vehicle  106 . For example, the secondary device  324  may be a second data acquisition device and may generate a command signal that instructs the control system  108  how to initiate one or more operations without changing a configuration setup of the control system  108 . The secondary device  324  generates the command signals that are communicated to the control system  108  in order for the controller  104  to receive the complete status data (e.g., in order to obtain the status data that is lacking) of the vehicle  106  to determine a condition of the components, systems, or the like of the vehicle  106  during the inspection event and/or maintenance event. 
     As one example, the memory  212 , the control system sensors  230 , or the control system  108  does not have the first sensor information indicative of temperature measurements of the coolant in the cooling system to determine if the heat exchanger of the cooling system is reducing the temperature of the coolant or if the heat exchanger is not reducing the temperature of the coolant. The secondary device  324  may direct the control system  108  of the vehicle  106  to initiate a second operation of the propulsion subsystem  208  (e.g., change a brake setting, or the like) as the propulsion subsystem  208  would normally operate during movement or during an operational state/phase other than an inspection state. For example, the secondary device  324  may direct the vehicle  106  to move around a railyard in order to check the status of the brakes, the engine, the distributed power arrangement, or the like. The secondary device  324  may direct the control system  108  to pump coolant through the cooling system in order to measure the temperature of the coolant. As another example, the control system  108  does not have pressure measurements of the air brake system to determine if the air brake system is operating to increase the pressure in the brake system. The secondary device  324  may instruct the control system  108  to apply the air brakes in order to obtain second sensor information from the external sensor systems  130  and/or the control system sensors  230  that is indicative of the time it takes for the air pressure within the air brake system to increase. 
     The secondary device  324  directs the control system  108  to perform an operation (e.g., a second operation) to obtain second sensor information when the control system  108  does not have the first sensor information. The different, second operation of the vehicle that the secondary device  324  instructs the control system  108  to perform is an operation that the vehicle  106  only performs during movement of the vehicle. For example, during a typical inspection event, individual systems and/or components may be inspected, and the individual systems and/or components may be forced into operation. For example, the air brakes may be engaged or disengaged, the cooling system may be pressurized or depressurized, electrical wiring may be tested, the radiator cap may be visually checked for defects, or the like. Alternatively, the controller  104  directs the control system  108  to initiate operations of the vehicle as the vehicle would operate during normal operation in order to obtain sensor information when the systems and components of the vehicle  106  work together. In one example, the electrical wiring may be tested by individually controlling electrical contacts in order to determine a power ground circuit. 
     The controller  104  instructs the vehicle  106  to perform operations without the vehicle  106  being aware that the vehicle  106  is being inspected and/or maintained. For example, the secondary device  324  may instruct the propulsion subsystem  208  to operate at a throttle setting (e.g., a speed that mimics a speed the vehicle would normally travel at during movement up an increasing terrain along a route), and subsequently direct the propulsion subsystem  208  to increase a brake setting (e.g., a brake setting that mimics a setting the vehicle would normally apply at a decreasing terrain along the route). By instructing the vehicle to perform operations that the vehicle would perform during normal operation of the vehicle, the controller  104  may obtain sensor information indicating the state of the vehicle when the vehicle systems and/or components function together. For example, information regarding the discharge of air from the air brakes as well as information around the air compressor operating conditions can be collected as sensor information indicative of a state of the braking system, the air compressor, the air conduits, or the like. 
     In the illustrated embodiment of  FIG. 3 , the primary device  322  and the secondary device  324  are shown as being connected with the controller  104 . Optionally, one or more of the primary device  322  or the secondary device  324  may be transferably coupled with the controller  104 . Additionally or alternatively, the controller  104  may include the primary device  322  and may not include the secondary device  324 . For example, the secondary device  324  may be coupled to the control system  108  of the vehicle and wirelessly communicate with the controller  104 . 
     Additionally or alternatively, in one or more embodiments, the primary device  322  may be unable to obtain the requested status information if the control system  108  is not equipped with the correct control system sensors  230 . For example, the vehicle  106  may not be equipped with a coolant temperature sensor, a manifold absolute pressure sensor, an air flow meter, or an alternative sensing device configured to indicate the state of the vehicle  106  and/or the state of one or more components and/or systems of the vehicle  106 . One or more external sensor systems  130  may be selectively coupled with the vehicle  106  in order for the controller  104  to obtain sensor information from the external sensor systems  130  indicating the state of the vehicle  106 , the state of components of the vehicle  106 , the state of the systems of the vehicle  106 , or the like. 
     Additionally or alternatively, in one or more embodiments, a maintenance tool (not shown) may be coupled with the controller  104  during a maintenance event for the vehicle  106 , for a sensor of the vehicle  106 , for the control system  108 , or the like. For example, the maintenance tool may be a cleaning device, such as a pressure washer, that is coupled with the controller  104 . The controller  104  may autonomously or semi-autonomously direct the cleaning device to operate when the vehicle  106  is stationary, until a cleaning process is complete, until the controller  104  confirms that the cleaning operation is complete, for a designated length of time, or the like. Optionally, the maintenance tool may be any alternative device that receives instructions from the controller  104  to perform an operation in accordance with the received instructions, for example, to assist with the vehicle inspection event. 
     Returning to  FIG. 1 , the controller  104  is configured to obtain sensor information of the vehicle  106  by sending command signals to the control system  108  onboard the vehicle  106 . The command signals may be one or more of requests for sensor information, instructions for the control system  108  to initiate an operation by the vehicle  106 , or the like. For example, the controller  104  is configured to control or stimulate movement of the vehicle  106  by instructing the control system  108  to initiate one or more operations of the vehicle, wherein the one or more operations are one or more operations performed by the control system  108  during movement of the vehicle  106  prior to and/or subsequent to an inspection event of the vehicle  106  by the controller  104 . For example, the command signals may instruct the control system  108  to operate at a throttle setting that mimics a throttle setting of the vehicle  106  during a trip (e.g., before or after an inspection event). 
     The one or more processors of the controller  104  allows for inspection and/or maintenance of the vehicle  106  when the control system  108  lacks the sensor information indicative of the state of the vehicle  106 . The secondary device  324  manipulates the vehicle  106  into performing an operation that results in the sought sensor information data being generated. For example, the secondary device  324  sends command signals to the control system  108  directing the vehicle  106  to perform one or more operations that simulates real-world operations of the vehicle system  102 . The controller  104  obtains the sought sensor information that is generated to autonomously or semi-autonomously determine a condition of one or more components, one or more systems, or a combination therein, of the vehicle  106 . For example, the controller  104  determines a condition of the vehicle indicative that may be an operational state, a fault state, a damaged state, or the like, of one or more components and/or systems of the vehicle  106 . 
       FIG. 4  illustrates a schematic illustration of one example of the external sensor system  130  of  FIG. 1  in accordance with one embodiment.  FIG. 5  illustrates an exploded illustration of the external sensor system  130  in accordance with one embodiment.  FIGS. 4 and 5  will be discussed in detail together. In the illustrated embodiment, the external sensor system  130  is a sensor that is used to measure a temperature of one or more components, systems, or the like, of the vehicle  106 . Additionally or alternatively, the external sensor system  130  may be any alternative sensor used to sense alternative information (e.g., pressures, flow rates, vibrations, visual information, audio information, or the like). 
     The external sensor system  130  may be used to read one or more surface temperatures of the vehicle  106  and/or a temperature inside of the surfaces of the vehicle  106 . For example, the external sensor system  130  may be used to read the engine oil temperature, coolant temperature, or the like, of the vehicle  106 . Optionally, the external sensor system  130  may be used to read the ambient temperature of the vehicle  106 . Optionally, the external sensor system  130  may be used to read an alternative temperature. Additionally or alternatively, the external sensor system  130  may be an alternative sensor used to sense one or more characteristics of the vehicle  106 , one or more characteristics of the environment of the vehicle  106 , or any combination therein. For example, the external sensor system  130  may be used to determine an externality characteristic of the external sensor system  130  that may be indicative of one or more external conditions to which the external sensor system  130  is exposed. Additionally or alternatively, the externality characteristic may indicate one or more external conditions to which the vehicle  106  is exposed. The externality characteristics may include an ambient temperature, an ambient humidity, an ambient barometric pressure, or the like. 
     The external sensor system  130  has a magnet  402  that is used to maintain a position of the external sensor system  130  at a location of the vehicle  106 . For example, the magnet may keep the external sensor system  130  pressed against a curved metal pipe, a flat metal surface, wall, or the like, of the vehicle  106 . The magnet  402  has a first side  422 , second sides  424 , and a gap  426  between the second sides  424 . In the illustrated embodiment, the magnetic  402  is generally C-shaped. Alternatively, the magnet  402  may have any alternative shape and/or size. Additionally or alternatively, the external sensor system  130  may use an alternative method and/or material to maintain a position at a location. For example, the sensor system  130  may be adhered to a surface with an adhesive material. 
     The external sensor system  130  has a first support layer  404  and a second support layer  406 . The first support layer  404  is sized and/or shaped in order to be positioned inside of the gap  426  of the magnet  402  when the external sensor system  130  is assembled. For example, the first support layer  404  may be manufactured of a flexible or rigid material such as foam, or the like. A first side  428  of the first support layer  404  is received into the gap  426  of the magnet  402 . The first support layer  404  is essentially cubed in shape and is sized and/or shaped in order to substantially fill the gap  426 . Alternatively, the first support layer  404  may have any alternative shape and/or size. Optionally, the external sensor system  130  may be devoid of the first support layer  404 . For example, the magnet  402  may have an alternative shape that is devoid the gap  426 , and the system  130  may be devoid the first support layer  404  that substantially fills the gap  426 . 
     The second support layer  406  is sized and/shaped in order to be positioned on the second sides  424  of the magnet  402 . The second support layer  406  has a rectangular cross-sectional shape and is manufactured of a flexible material, a rigid material, or any alternative material. For example, in the illustrated embodiment, the second support layer  406  is a strengthened foam material, such as Styrofoam, having a first side  432  and a second side  434 . The first side  432  that is operably coupled to a second side  430  of the first support layer  404  and operably coupled to the second sides  424  of the magnet  402 . For example, the first side  432  of the second support layer  406  may be pressed up against the second side  430  of the first support layer  404 . The first support layer  404  provides support for the second support layer  406  at the gap  426  when the external sensor system  130  is assembled. For example, the first support layer  404  may prevent the second support layer  406  from curving, bending, or the like, into the gap  426  when the external sensor system  130  is assembled, when the sensor system  130  is mounted to a surface of the vehicle  106 , or the like. The first support layer  404  enables the second support layer  406  to remain positioned essentially flat between the second sides  424  of the magnet  402 . 
     The system  130  includes a temperature sensor  410  that reads the temperature of the surface that the system  130  is operably coupled to. For example, the temperature sensor  410  may be a thermistor, a resistance temperature detector, a heat flux sensor, a temperature gauge, a thermocouple, or the like. A first end  438  of the temperature sensor  410  is disposed between a thermal conductive layer  408  and the second support layer  406 . The thermal conductive layer  408  transfers heat from the surface that the external sensor system  130  is operably coupled with to the sensor  410 , and the second support layer  406  isolates (e.g., thermally, physically, or the like) the first end  438  of the sensor  410  from the magnet  402 , convection to ambient air, or the like. A second end  436  of the temperature sensor  410  extends a distance away from the thermal conductive layer  408  and through a passage  448  of the magnet  402 . For example, the second end  436  extends a distance away from the system  130  in order to be operably coupled to the control system  108 , the controller  104 , an alternative sensor reader, or the like. 
     The thermal conductive layer  408  that has a first side  440  that is coupled to the second side  434  of the second support layer  406  when the sensor system  130  is assembled. For example, the thermal conductive layer  408  may be a thermal pad that transfers heat from the surface that the external sensor system  130  is operably coupled with to pass through the thermal conductive layer  408  to the first end  438  of the sensor  410 . 
     The first support layer  404 , the second support layer  406 , the thermal conductive layer  408  and the temperature sensor  410  may be held in an assembled position with the magnet  402  with one or more conductive adhesive layers  412 . For example, the conductive adhesive layer  412  may be one or more pieces of a conductive tape with an adhesive side  444  and a non-adhesive side  446 . The adhesive side  444  of the conductive adhesive layer  412  is adhered to the magnet  402  in order to assemble the external sensor system  130 . The conductive adhesive layer  412  may enable heat to be transferred from the surface to which the external sensor system  130  is coupled to, to the temperature sensor  410 . 
       FIG. 6  illustrates a flowchart of a method  600  for inspecting and/or maintaining a vehicle with the inspection system  100  in accordance with one embodiment. At  602 , one or more sensors are selectively coupled to a vehicle during an inspection event and/or a maintenance for a vehicle  106 . For example, one or more external sensor systems  130  may be transferably coupled to the vehicle  106  to inspect the vehicle  106 . At  604 , the controller  104  is operably coupled with the control system  108  that controls operations of the vehicle  106 , and is operably coupled with the one or more sensors. The controller  104  is operably coupled with the control system  108  in order to cause the control system  108  to initiate one or more operations of the vehicle  106  during the inspection event and/or maintenance event. Additionally, the controller  104  is operably coupled the control system sensors  230  and the one or more external sensor systems  130  in order to obtain sensor information indicative of a state of the vehicle  106 . 
     At  606 , a decision is made by the controller  104  to determine if the control system  108  has first sensor information indicative of a state of the vehicle during a first operation of the vehicle  106 . For example, the vehicle  106  may have over-heated and the vehicle  106  is transferred to a repair center. The controller  104  may request first sensor information from the memory  212  of the control system  108 , from the control system sensors  230 , from the external sensor systems  130 , or any combination of one or more of therein, that is indicative of the state of the vehicle  106 , for example, when the vehicle  106  overheated. For example, the controller  104  may request sensor information of the first operation of the vehicle  106 . The first operation of the vehicle  106  may be to bring engine speed of the vehicle  106  to a first throttle setting in order to gather information that includes radiator shutter functionality, radiator cooling fan functionality, coolant flow rates, engine oil temperature measurements, engine coolant temperature measurements, engine lube temperature measurements, or the like, during the first operation of the vehicle  106 . The first sensor information may be in the form of numerical data, graphical data, statistical data, pass/fail indicator, or the like. Optionally, the first sensor information may include current and/or stored operational data associated with the vehicle system  102 . For example, the first sensor information may include operational data and/or maintenance data of the radiator shutter stored in the memory  212 . If the controller  104  determines that the control system  108  does have the first sensor information indicative of the state of the vehicle  106 , then flow of the method proceeds towards  612 . Alternatively, if the controller  104  determines that the control system  108  does not have the first sensor information indicative of the state of the vehicle  106 , then flow of the method proceeds towards  608 . 
     Additionally or alternatively, in one or more embodiments the controller  104  may determine if the control system  108  of the first and second vehicles  106 A,  160 B have the first sensor data. For example, the controller  104  may be operably coupled with the control system  108  of the first vehicle  106 A, and may request sensor information from both the first and second vehicles  106 A,  106 B in order to determine a condition of one or more of the first or second vehicles  106 A,  106 B and/or of the vehicle system  102 . The control system  108  of the first vehicle  106 A may operate using the distributed power configuration of the vehicle system  102  (of  FIG. 1 ) to communicate the request signal to the second vehicle  106 B via the communication link  112 . 
     At  608 , the controller  104  sends a command signal to the control system  108  from the controller  104  in order to direct the control system  108  to change vehicle operations from the first operation to a different, second operation. For example, the first sensor information that is sensed during the first operation of the vehicle  106  may not indicate the condition of the vehicle  106 . The secondary device  324  of the controller  104  may send a command signal to the control system  108  instructing the control system  108  to operate at a second operation. For example, the second operation may be to bring the engine speed of the vehicle  106  to a second throttle setting that is greater than the first throttle setting, in order to gather second sensor information that includes radiator shutter functionality, radiator cooling fan functionality, coolant flow rates, engine oil temperature measurements, engine coolant temperature measurements, engine lube temperature measurements, or the like, during the second operation of the vehicle  106 . For example, the controller  104  may instruct the control system  108  to change one or more operations of components or systems of the vehicle  106  that force the components or systems to change, relative to waiting for the components or systems to change independently. The controller  104  may instruct the control system  108  to initiate one or more operations that are performed by the control system  108  during movement of the vehicle  106 . For example, the command signals from the controller  104  may instruct the control system  108  to operate as it would operate (e.g. normal and/or typical throttle settings, brake settings, speed settings, radiator fan speeds, pump speeds, coolant flow rates, or the like) prior to and/or subsequent to the controller  104  determining a condition of the vehicle. For example, the control system  108  may instruct the propulsion subsystem  208  to operate at full power, to operate at varying intervals of increasing and/or decreasing power, to operate at full power then increase the brake setting (e.g., settings that mimic normal or typical operations of the vehicle traveling along the route). 
     Additionally, by instructing the control system  108  to perform one or more operations with the vehicle  106  that are normal and/or typical operations of the vehicle  106 , the controller  104  does not change a configuration setup of the control system  108 . For example, the controller  104  may instruct the control system  108  to initiate an operation such that the performed operation does not require the control system  108  to change a configuration or setup between the control system  108  and the propulsion subsystem  208 , the energy management system  217 , or any other system. 
     Additionally or alternatively, the controller  104  may not be able to instruct the control system  108  to perform one or more operations. For example, the vehicle  106  may be an old vehicle model with a control system  108  that that is not compatible with and/or cannot receive all command signals from the controller  104 . An operator of the vehicle  106  and/or the controller  104  may instruct the vehicle  106  to perform one or more operations with the vehicle  106  in order for the controller  104  to obtain the sensor information of the vehicle  106 . 
     Additionally or alternatively, in one or more embodiments, the controller  104  may send a command signal to the control system  108  of the first vehicle  106 A instructing the control system  108  of the second vehicle  106 B to perform one or more operations. For example, the control system  108  of the first vehicle  106 A may utilize the distributed power configuration of the vehicle system  102  (of  FIG. 1 ) to communicate the command signal to the second vehicle  106 B via the communication link  112  in order for the controller  104  to determine a condition of the second vehicle  106 B. 
     At  610 , the controller  104  obtains the second sensor information based on the second operation of the vehicle  106 . For example, the controller  104  may obtain the second sensor information from one or more of the external sensor system  130 , the control system sensors  230 , or the memory  212 . The control system  108  communicates the second sensor information based on the performed second operations of the vehicle  106  to the controller  104  (e.g., via the communication link  120 ). 
     At  612 , the controller  104  determines a condition of the vehicle  106 , a condition of one or more components of the vehicle  106 , or a condition of one or more systems of the vehicle, based on the first and second sensor information that is indicative of an operational state, a fault state, a damaged state, of the components and/or systems of the vehicle. The fault state may be indicative of one or more of a faulty system of a faulty component; the damaged state may be indicative of a level of damage to a system or a component; the operational state may be indicative of the functionality of a system or a component. For example, the controller  104  may determine that the radiator shutters do not actuate when the engine speed exceeds a determined limit; may determine that the air compressor of the brake system fails to increase the pressure of in the brake system within a minimum time limit; may determine that the heat exchanger does not reduce the temperature of the coolant in the cooling system to a designated temperature; may determine that the radiator cooling fan operates only when the temperature of the cooling system is below a determined temperature; may determine that the water tank of the cooling system leaks water; may determine that the oil pressure drop across a lube oil cooler and filter exceeds a designated pressure threshold; or the like. 
     In one embodiment, the controller  104  determines a condition and diagnoses an operational state of the vehicle  106  based on one or more of the operating characteristic of the vehicle determined by a first sensor, on the externality characteristic of the first sensor determined by a second sensor, or on the externality characteristic of the vehicle  106  determined by the second sensor. For example, the control system sensors  230  may have the sensor information indicative of the operating characteristic of the vehicle  106 . The control system sensors  230  (e.g., a cooling system temperature sensor) may determine that the heat exchanger is not reducing the temperature of the coolant in the cooling system of the vehicle  106 . The external sensor systems  130  may determine one or more externality characteristics representative of one or more external conditions to which the control system sensors  230  are exposed. For example, the external sensor systems  130  may determine that the control system sensors  230  are disposed at a location onboard the vehicle  106  that is hotter relative to alternative locations onboard the vehicle  106 . For example, the external sensor systems  130  may determine that the control system sensors  230  are disposed near the engine exhaust conduit which may have a higher temperature than the engine coolant inlet conduit. Additionally or alternatively, the external sensor system  130  may determine one or more externality characteristics representative of one or more external conditions to which the vehicle  106  is exposed. For example, the external sensor systems  130  may determine that the vehicle  106  is being inspected and/or maintained at a first repair center that has a higher humidity relative to a different, second repair center. For example, the vehicle  106  may be inspected at a location in Florida that has a greater ambient humidity level than a repair center located in Colorado. The externality conditions of the vehicle and the sensors may impact the operational characteristic of the vehicle  106 . For example, an operating vehicle  106  exposed to a higher ambient temperature may overheat more quickly relative to an operating vehicle  106  exposed to a lower ambient temperature; a vehicle exposed to a higher ambient humidity may cause the electric wiring to short more easily relative to a vehicle exposed to a lower ambient humidity. Optionally, the first external sensor system  130 A may determine the externality characteristics of the control system sensors  230  and/or the vehicle  106  when the vehicle  106  is operating at a first geographical location, and alternatively the second external sensor system  130 B may determine the externality characteristics of the control system sensors  230  and/or the vehicle  106  when the vehicle  106  is operating at a second geographical location. 
     At  614 , a decision is made if the determined condition of the vehicle  106  requires a responsive action to be implemented. For example, the controller  104  may determine whether or not to implement a responsive action in response to determining that the radiator shutter is failing to actuate, in response to the radiator cooling fan operating only when the temperature of the cooling system is below a determined temperature, in response to determining that the water tank of the cooling system has a leak, or the like. If a responsive action is required, then flow of the method proceeds towards  616 . If a responsive action is not required (e.g., a component and/or system does not need to be repaired, replaced, inspected further, or the like), then flow of the method proceeds towards  620 . 
     At  616 , a responsive action from plural different response actions is selected to be implemented. For example, if the controller  104  has determined a condition of the components and/or systems of the vehicle  106  based on the first and second sensor information, then a responsive action may be selected in order to repair, correct, fix, improve the fault state, improve the state of health, or the like, of one or more components the vehicle  106 . The plural different responsive actions may include one or more of scheduling routine maintenance of the vehicle, scheduling non-routine maintenance (e.g., immediate) of the vehicle, not taking any responsive action, repair or replace a damaged or worn component of the vehicle, repair or replace a damaged system of the vehicle, generate a work order for maintenance in order to repair or replace the component and/or system, notify the operator of the vehicle system  102  that the controller  104  has identified a condition of the system or component that requires a responsive action, update a status of the vehicle  106  indicating to one or more operators or other vehicles the condition of the vehicle  106 , store the first and second sensor information in the memory  326  of the controller  104 , store the determined faulty state (e.g., the faulty component, faulty system, or the like) in the memory  326  of the controller  104 , schedule a cleaning operation in order to clean a component, the vehicle  106  and/or vehicle system using the cleaning device, or the like. Additionally or alternatively, the selected responsive action may be any alternative responsive action. 
     At  618 , the responsive action that is selected from the plural different responsive actions is implemented. For example, if the controller  104  has determined that the vehicle  106  has a damaged radiator shutter, then the controller  104  may autonomously and/or semi-autonomously generate a work order identifying the damaged radiator shutter and schedule non-routine maintenance (e.g., immediate) of the vehicle  106  in order to replace the damaged radiator shutter. Additionally or alternatively, if the controller  104  has determined that the vehicle  106  has a measured volume of coolant that is below a designated threshold (e.g., the engine is overheating), then the controller  104  may autonomously or semi-autonomously generate a work order with instructions to add coolant to the cooling system of the vehicle  106 . 
     At  620 , the controller  104  determines a health score of the vehicle  106  based on the determined condition of the vehicle, the components, or the systems of the vehicle. For example, the controller  104  may determine that the vehicle  106  has a low health score (e.g., the vehicle is in poor health) if the difference between the first and second sensor information and predetermined target values of sensor information is high (e.g., above or greater than a designated threshold). For example, the sensor information may indicate that the volume of coolant flowing through the cooling system is low, however the measured volume of coolant flowing through the cooling system is a value greater than a predetermined target volume of coolant (e.g., not a fault state). Then the controller  104  may indicate that the health score of the cooling system of the vehicle  106  is low. Alternatively, if the measured volume of coolant flowing through the cooling system is high (e.g., is a measured value generally close to the predetermined target volume value), then the controller  104  may indicate that the health score of the cooling system of the vehicle  106  is high (e.g., the vehicle is in good health). In another example, the controller  104  has determined that a radiator shutter is damaged. The controller  104  may indicate that the health score of the cooling system of the vehicle  106  is low (e.g., the vehicle is in poor health) in response to the determined damaged radiator shutter. 
     In one or more embodiments, the controller  104  is coupled with the first vehicle  106 A in order to diagnose a state of health of the first vehicle  106 A. The controller  104  may be subsequently transferred off-board the first vehicle  106 A and onboard the second vehicle  106 B and coupled with the control system  108  that is onboard the second vehicle  106 B in order to determine a condition of the second vehicle  106 B. For example, the controller  104 , when onboard the first vehicle  106 A, may instruct the control system  108  of the first vehicle  106 A to perform a first set of operations, and may autonomously diagnose a first condition (e.g., a malfunctioning radiator shutter) of the first vehicle  106 A. The controller  104 , when onboard the second vehicle  106 B, may instruct the control system  108  of the second vehicle  106 B to perform a second set of operations, wherein the second set of operations may be unique or the same as the first set of operations instructed to the first vehicle  106 A. Additionally, the controller  104  may autonomously diagnose a second condition (e.g., engine coolant volumes are too low, or are below a designated threshold) of the second vehicle  106 B. Alternatively, the second condition may be the same as the first condition of the first vehicle. 
     In one embodiment of the subject matter described herein, an inspection system includes one or more sensors that are selectively coupled to a vehicle during one or more of an inspection event or a maintenance event for the vehicle and a controller that is operable to cause a control system of the vehicle that controls plural operations of the vehicle to initiate a first operation and a different, second operation of the plural operations of the vehicle. The controller is configured to determine whether the control system of the vehicle has first sensor information indicative of a state of the vehicle during the first operation of the vehicle. The controller is configured to send a command signal to the control system of the vehicle in order to direct the control system of the vehicle to change vehicle operations from the first operation to the second operation of the vehicle responsive to determining that the control system lacks the first sensor information that was requested. The controller obtains second sensor information from the one or more sensors based on the second operation of the vehicle and determines a condition of one or more components of the vehicle based on the first sensor information and the second sensor information. 
     Optionally, the first and second operations of the vehicle that are directed by the controller are operations performed by the control system during movement of the vehicle. 
     Optionally, the condition is indicative of one or more of an operational state, a fault state, or a damaged state of the one or more of the components of the vehicle. 
     Optionally, the controller is configured to determine a health score of the vehicle based on the condition of the one or more of the components of the vehicle. 
     Optionally, the controller is configured to one or more of autonomously or semi-autonomously determine the condition of the one or more components of the vehicle. 
     Optionally, the controller is configured to control movement of the vehicle with the control system during the one or more of the inspection event or the maintenance event for the vehicle. 
     Optionally, the controller is configured to select a responsive action to implement from plural different responsive actions based on the condition of the one or more of the components of the vehicle. 
     Optionally, a first sensor of the one or more sensors is configured to determine an operating characteristic of the vehicle, and a second sensor of the one or more sensors is configured to determine an externality characteristic of the first sensor, wherein the externality characteristic is representative of one or more external conditions to which the first sensor is exposed. 
     Optionally, the controller is configured to diagnose an operational state of the vehicle based on the operating characteristic of the vehicle and based on the externality characteristic of the first sensor. 
     In one embodiment of the subject matter described herein, a method includes selectively coupling one or more sensors of an inspection system to a vehicle during one or more of an inspection event or a maintenance event for the vehicle. The method includes operably coupling a controller with the one or more sensors of the inspection system wherein the controller is operable to cause a control system of the vehicle to initiate a first operation of the vehicle and a different, second operation of the vehicle. During the first operation of the vehicle it is determined whether the control system of the vehicle has first sensor information indicative of a state of the vehicle. Responsive to determining that the control system lacks the first sensor information, the controller sends a command signal to the control system of the vehicle in order to direct the control system of the vehicle to change vehicle operations from the first operation to the second operation of the vehicle by sending a command signal to the control system of the vehicle. Second sensor information is obtained from the one or more sensors based on the second operations of the vehicle. A condition of one or more components of the vehicle is determined based on the first sensor information and the second sensor information. 
     Optionally, the first and second operations of the vehicle that are directed by the controller are operations performed by the control system during movement of the vehicle. 
     Optionally, the method also includes determining a health score of the vehicle based on the condition of the one or more of the components of the vehicle. 
     Optionally, determining the condition of the vehicle is carried out by the controller one or more of autonomously or semi-autonomously. 
     Optionally, the method also includes selecting a responsive action to implement from plural different responsive actions based on the condition of the one or more of the components of the vehicle. 
     Optionally, the method also includes determining, with a first sensor of the one or more sensors, an operating characteristic of the vehicle, and determining with a second sensor of the one or more sensors, an externality characteristic of the first sensor, wherein the externality characteristic is representative of one or more external conditions to which the first sensor is exposed. 
     Optionally, the method also includes diagnosing an operational state of the vehicle based on the operating characteristic of the vehicle and based on the externality characteristic of the first sensor. 
     In one embodiment of the subject matter described herein, a system includes a first sensor configured to determine an operating characteristic of a vehicle and a second sensor configured to determine one or more of an externality characteristic of the first sensor or an externality characteristic of the vehicle. The externality characteristic of the first sensor is representative of one or more external conditions to which the first sensor is exposed. The externality characteristic of the vehicle is representative of one or more external conditions to which the vehicle is exposed. The system includes a controller configured to diagnose an operational state of the vehicle based on the operating characteristic of the vehicle and based on the one or more of the externality characteristic of the first sensor or the externality characteristic of the vehicle 
     Optionally, the controller is operable to cause a control system of the vehicle that controls operations of the vehicle to initiate one or more of the operations of the vehicle. The controller is configured to obtain one or more of the operating characteristics or the externality characteristics responsive to initiating the one or more operations of the vehicle in order to diagnose the operational state of the vehicle. 
     Optionally, the controller is configured to determine a health score of the vehicle based on the operational state of the vehicle. 
     Optionally, the controller is configured to one or more of autonomously or semi-autonomously diagnose the operational state of the vehicle. 
     Optionally, the controller is configured to select a responsive action to implement from plural different responsive actions based on the operational state of the vehicle. 
     In one embodiment of the subject matter described herein, a method includes requesting status data of a control system that controls operation of a vehicle from an inspection system that is off-board the vehicle during movement of the vehicle. The method includes determining whether the control system of the vehicle has the status data indicative of a state of the vehicle. Responsive to determining that the control system lacks the status data that was requested, the method includes directing the control system of the vehicle to perform one or more operations with the vehicle by sending a command signal to the control system of the vehicle from the inspection system without changing a configuration setup of the control system, obtaining the status data that was requested based on the performance of the one or more operations by the vehicle, and determining a fault state of the vehicle based on the one or more operations at the inspection system. 
     Optionally, the one or more operations of the vehicle that are directed by the inspection system are one or more operations performed by the control system during movement of the vehicle one or more of prior to or subsequent to inspection of the vehicle by the inspection system. 
     Optionally, the fault state is indicative of one or more of a faulty system or a faulty component. 
     Optionally, the method further includes diagnosing the fault state as one or more of a faulty system or a faulty component of the vehicle, wherein diagnosing the one or more of the faulty system or the faulty component includes selecting a responsive action to implement from plural different responsive actions. 
     Optionally, the method further includes implementing the responsive action that is selected from the plural different responsive actions. 
     Optionally, the method further includes determining a health score of the vehicle based on one or more of the state of the vehicle of the fault state of the vehicle from the inspection system. 
     Optionally, the method further includes controlling movement of the vehicle with the control system while the inspection system is onboard the vehicle. 
     In another embodiment of the subject matter described herein, a system includes an inspection system that is off-board a vehicle during movement of the vehicle. The inspection system includes one or more processors configured to request status data of a control system that controls operations of the vehicle. The one or more processors are configured to determine whether the control system of the vehicle has the status data indicative of a state of the vehicle, direct the control system of the vehicle to perform one or more operations with the vehicle by sending a command signal to the control system of the vehicle without changing a configuration setup of the control system responsive to determining that the control system lacks the status data that was requested, obtain the status data that was requested based on the performance of the one or more operations by the vehicle, and determine a fault state of the vehicle based on the one or more operations at the inspection system. 
     Optionally, the one or more operations of the vehicle that are directed by the inspection system are one or more operations performed by the control system during movement of the vehicle one or more of prior to or subsequent to inspection of the vehicle by the inspection system. 
     Optionally, the fault state is indicative of one or more of a faulty system or a faulty component. 
     Optionally, the one or more processors are configured to diagnose the fault state as one or more of a faulty system or a faulty component of the vehicle, wherein diagnosing the one or more of the faulty system or the faulty component includes selecting a responsive action to implement from plural different responsive actions. 
     Optionally, the one or more processors are configured to implement the responsive action that is selected from the plural different responsive actions. 
     Optionally, the one or more processors are configured to determine a health score of the vehicle based on one or more of the state of the vehicle or the fault state of the vehicle. 
     Optionally, the one or more processors are configured to control movement of the vehicle with the control system while the inspection system is onboard the vehicle. 
     Optionally, the one or more processors are configured to autonomously determine the fault state of the vehicle. 
     Optionally, the inspection system further includes a primary device and a secondary device, wherein the primary device determines the state of the vehicle and the secondary device determines the fault state of the vehicle. 
     In another embodiment of the subject matter described herein, a system includes an inspection system that is off-board a vehicle during movement of the vehicle. The inspection system includes one or more processors configured to request status data of a control system that controls operations of the vehicle. The one or more processors are configured to determine whether the control system of the vehicle has the status data indicative of a state of the vehicle. The one or more processors are configured to direct the control system of the vehicle to perform one or more operations with the vehicle by sending a command signal to the control system of the vehicle without changing a configuration setup of the control system responsive to determining that the control system lacks the status data that was requested. The one or more processors are configured to obtain the status data that was requested based on the performance of the one or more operations by the vehicle, determine a fault state of the vehicle based on the one or more operations at the inspection system, and determine a health score of the vehicle based on one or more of the state of the vehicle or the fault state of the vehicle. 
     Optionally, the one or more operations of the vehicle that are directed by the inspection system are one or more operations performed by the control system during movement of the vehicle one or more of prior to or subsequent to inspection of the vehicle by the inspection system 
     Optionally, the fault state is indicative of one or more of a faulty system or a faulty component. 
     Optionally, the one or more processors are configured to diagnose the fault state as one or more of a faulty system or a faulty component of the vehicle, wherein diagnosing the one or more of the faulty system or the faulty component includes selecting a responsive action to implement from plural different responsive actions and implementing the responsive action that is selected from the plural different responsive actions. 
     This written description uses examples to disclose several embodiments of the inventive subject matter and also to enable one of ordinary skill in the art to practice the embodiments of inventive subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the inventive subject matter is defined by the claims, and may include other examples that occur to one of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. 
     The foregoing description of certain embodiments of the present inventive subject matter will be better understood when read in conjunction with the appended drawings. To the extent that the figures illustrate diagrams of the functional blocks of various embodiments, the functional blocks are not necessarily indicative of the division between hardware circuitry. Thus, for example, one or more of the functional blocks (for example, processors or memories) may be implemented in a single piece of hardware (for example, a general purpose signal processor, microcontroller, random access memory, hard disk, and the like). Similarly, the programs may be stand-alone programs, may be incorporated as subroutines in an operating system, may be functions in an installed software package, and the like. The various embodiments are not limited to the arrangements and instrumentality shown in the drawings. 
     As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” of the present inventive subject matter are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising,” “including,” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property. 
     It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the subject matter set forth herein without departing from its scope. While the dimensions and types of materials described herein are intended to define the parameters of the disclosed subject matter, they are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the subject matter described herein should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. § 112(f), unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.