Patent Publication Number: US-10787124-B2

Title: Methods and apparatus to facilitate pedestrian detection during remote-controlled maneuvers

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/121,078 filed Sep. 4, 2018, which is herein incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to automated vehicle features and, more specifically, remote-controlled vehicle maneuvers and pedestrian detection. 
     BACKGROUND 
     In recent years, vehicles have been equipped with automated vehicle maneuvering features such as parallel parking assistance, trailer-hitching assistance, braking assistance, etc. Automated vehicle maneuvering features often make vehicles more enjoyable to drive, alert drivers to potential obstructions, and/or assist drivers in making relatively precise maneuvers. Information from automated vehicle maneuvering features is often presented to a driver via an interface of a vehicle. 
     SUMMARY 
     The appended claims define this application. The present disclosure summarizes aspects of the embodiments and should not be used to limit the claims. Other implementations are contemplated in accordance with the techniques described herein, as will be apparent to one having ordinary skill in the art upon examination of the following drawings and detailed description, and these implementations are intended to be within the scope of this application. 
     An example vehicle is disclosed. The vehicle comprises: external indicators and a processor and memory. The processor and memory are in communication with the external indicators and a remote device. The processor is configured to: determine whether the remote device is in a travel zone related to the vehicle; determine a risk assessment if the remote device is in the travel zone; and communicate a warning based on the risk assessment via the external indicators. 
     An example method is disclosed. The method comprises: determining, with a processor, whether a remote device is in a travel zone related to a vehicle; determining, with the processor, a risk assessment if the remote device is in the travel zone; and communicating, with external indicators of the vehicle, a warning based on the risk assessment to a driver. 
     An example system is disclosed. The system comprises: a mobile device; a key fob; and a vehicle. The vehicle comprises wheels; external indicators; and a processor and memory. The processor and memory are in communication with the mobile device, the remote device, and the external indicators. The processor is configured to: control the wheels based on signals from the mobile device; determine whether the remote device is in a travel zone related to the vehicle; determine a risk assessment if the remote device is in the travel zone; and communicate a warning based on the risk assessment via one or more of the external indicators and the mobile device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the invention, reference may be made to embodiments shown in the following drawings. The components in the drawings are not necessarily to scale and related elements may be omitted, or in some instances proportions may have been exaggerated, so as to emphasize and clearly illustrate the novel features described herein. In addition, system components can be variously arranged, as known in the art. Further, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is a side schematic view of a vehicle operating in accordance with the teachings of this disclosure in an environment. 
         FIG. 2  is a top schematic view of the vehicle of  FIG. 1 . 
         FIG. 3  is a block diagram of the electronic components of the vehicle of  FIG. 1 . 
         FIG. 4  is a more detailed block diagram of the risk analyzer of  FIG. 3 . 
         FIG. 5  illustrates an example travel zone defined by the risk analyzer of  FIG. 3 . 
         FIG. 6  illustrates another example travel zone defined by the risk analyzer of  FIG. 3 . 
         FIG. 7  illustrates another example travel zone defined by the risk analyzer of  FIG. 3 . 
         FIG. 8  illustrates another example travel zone defined by the risk analyzer of  FIG. 3 . 
         FIG. 9  is a look-up table stored in a memory of the electronic components of  FIG. 8 . 
         FIG. 10  illustrates a mobile device used to remotely control the vehicle of  FIG. 1 . 
         FIG. 11  is a flowchart of a method to prevent contact between the vehicle of  FIG. 1  and a driver during a remote-controlled maneuver, which may be implemented by the electronic components of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS 
     While the invention may be embodied in various forms, there are shown in the drawings, and will hereinafter be described, some exemplary and non-limiting embodiments, with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated. 
     Automated vehicle maneuvering features include parallel parking assistance, trailer-hitching assistance, and braking assistance, among others. Parallel parking assistance detects and steers a vehicle into a parallel parking spot. Trailer-hitching assistance detects and steers a vehicle to a trailer hitch coupler. Braking assistance automatically slows and/or stops a vehicle when a pedestrian or other obstruction is detected near a vehicle. 
     Traditionally, with trailer-hitching assistance, a vehicle detects a hitch coupler of a trailer and a driver commands vehicle motion from the driver&#39;s seat by holding down a button. While the button is held, the vehicle reverses toward the trailer. However, this precludes the driver from monitoring a potential height mismatch between the vehicle&#39;s towing tongue and the trailer&#39;s hitch coupler. In some instances, the hitch coupler may be lower than the towing tongue. In some such instances, the vehicle must then be moved away from the trailer, the trailer raised, and the trailer-hitching assistance process repeated. 
     This disclosure provides methods and apparatus to remotely control vehicle maneuvers and detect pedestrians. By remotely controlling vehicle maneuvers, a driver may adjust a trailer hitch coupler&#39;s height before the vehicle arrives at the trailer. By detecting pedestrians, the vehicle may be stopped and/or provide a warning before the driver or other pedestrian is caught between the vehicle and the trailer. 
       FIG. 1  is a side schematic view of a vehicle  110  operating in in an environment  100 .  FIG. 2  is a top schematic view of the vehicle  110 . 
     As shown in  FIG. 1 , the environment  100  includes a roadway  101 , the vehicle  110 , the mobile device  171 , a key fob  172 , a driver  180 , and a trailer  190 . An arrow  111  shown in  FIG. 1  indicates that the vehicle  110  is traveling in reverse toward the trailer  190 . In the example of  FIG. 1 , the driver  180  is between the vehicle  110  and the trailer  190  to monitor the vehicle&#39;s  110  progress toward the trailer  190 . The vehicle  110  detects the trailer  190 , determines a path to the trailer, and steers itself toward the trailer  190 . The driver  180  controls the vehicle&#39;s  110  speed along the path via the mobile device  171 . In some examples, the driver  180  controls the vehicle&#39;s  110  speed by commanding the vehicle  110  to either stop (e.g., zero speed) or move at a set predetermined speed (e.g., 3 miles per hour, 5 miles per hour, etc.). 
     The vehicle  110  may be a standard gasoline powered vehicle, a hybrid vehicle, an electric vehicle, a fuel cell vehicle, and/or any other mobility implement type of vehicle. The vehicle  110  includes parts related to mobility, such as a powertrain with an engine, a transmission, a suspension, a driveshaft, and/or wheels, etc. The vehicle  110  may be non-autonomous, semi-autonomous (e.g., some routine motive functions controlled by the vehicle  110 ), or autonomous (e.g., motive functions are controlled by the vehicle  110  without direct driver input). As shown in  FIG. 1  the vehicle  110  includes wheels  112 , a towing ball  113 , sensors  120 , external indicators  130 , a transceiver  140 , an on board computing platform (OBCP)  150 , and an infotainment head unit (IHU)  160 . 
     The trailer  190  includes a hitch coupler  191 . The hitch coupler  191  is configured to receive and secure about the towing ball  113 . Thus, the trailer  190  may be swingably connected to the vehicle  110  via the towing ball  113  and the hitch coupler  191 . 
     The vehicle  110  is in communication with the mobile device  171  and the key fob  172  via the transceiver  140 . 
     The sensors  120  may be arranged in and around the vehicle  110  in any suitable fashion. The sensors  120  may be mounted to measure properties around the exterior of the vehicle  110 . Additionally, some sensors  120  may be mounted inside the cabin of the vehicle  110  or in the body of the vehicle  110  (such as, the engine compartment, the wheel wells, etc.) to measure properties in the interior of the vehicle  110 . For example, such sensors  120  may include accelerometers, odometers, tachometers, pitch and yaw sensors, wheel speed sensors, microphones, tire pressure sensors, and biometric sensors, etc. In the illustrated example, the sensors  120  are object-detecting and range-finding sensors (e.g., a camera, LIDAR, RADAR, ultrasonic, etc.). In some examples, the sensors  120  are mounted at the front and rear of the vehicle  110 . The sensors  120  detect objects (e.g., the trailer  190 , the driver  180 , etc.) about the vehicle  110 . In other words, the sensors  120  generate obstruction information for the vehicle  110 . 
     The external indicators  130  include a horn  131 , headlights and taillights  132 , windows  133 , internal speakers  134 , external speakers  135 , and a puddle lamp  136 . The external indicators  130  may be used to generate an escalating series of warnings for the driver  180  and/or other pedestrians between the vehicle  110  and the trailer  190  as the vehicle  110  reverses toward the trailer  190 . 
     The horn  131 , internal speakers  134 , and the external speakers  135  generate audio warnings (e.g., horn chirps, horn blasts, pre-recorded spoken messages, etc.). In some examples, the windows  133  are opened to aid in making an audio warning produced by the internal speakers  134  more audible to the driver  180  and/or other pedestrians outside the vehicle  110 . 
     The headlights and taillights  132  and the puddle lamp  136  generate visual warnings (e.g., light flashes, light displays, etc.). In some examples, the puddle lamp  136  casts a lighted image  137  on the roadway  101  during a remote-controlled auto-hitch maneuver, as shown in  FIG. 2 . The image  137  may include an outline of an area behind the vehicle  110  out of which the driver  180  and/or other pedestrians should stay. The image  137  may include a written message warning the driver  180  and/or other pedestrians to stay away from behind the vehicle  110 . The puddle lamp  136  may be any type of light source (e.g., light-emitting diode, incandescent, laser, etc.). 
     The example transceiver  140  includes antenna(s), radio(s) and software to broadcast messages and to establish connections between the vehicle  110 , the key fob  172 , and the mobile device  171 . 
     The OBCP  150  controls various subsystems of the vehicle  110 . In some examples, the OBCP  150  controls power windows, power locks, an immobilizer system, and/or power mirrors, etc. In some examples, the OBCP  150  includes circuits to, for example, drive relays (e.g., to control wiper fluid, etc.), drive brushed direct current (DC) motors (e.g., to control power seats, power locks, power windows, wipers, etc.), drive stepper motors, and/or drive LEDs, etc. In some examples, the OBCP  150  processes information from the sensors  120  to execute and support remote-control vehicle maneuvering features and automated vehicle maneuvering features. Using obstruction information provided by the sensors  120 , the OBCP  150  determines a path for the vehicle to follow to the trailer  190 , determines whether to warn the driver  180  and/or other pedestrians of the vehicle  110 &#39;s approach toward the trailer  190 , and/or determines whether to stop the vehicle  110  before contacting an obstruction. 
     The infotainment head unit  160  provides an interface between the vehicle  110  and a user. The infotainment head unit  160  includes digital and/or analog interfaces (e.g., input devices and output devices) to receive input from the user(s) and display information. The input devices may include, for example, a control knob, an instrument panel, a digital camera for image capture and/or visual command recognition, a touch screen, an audio input device (e.g., cabin microphone), buttons, or a touchpad. The output devices may include instrument cluster outputs (e.g., dials, lighting devices), actuators, a heads-up display, a center console display (e.g., a liquid crystal display (“LCD”), an organic light emitting diode (“OLED”) display, a flat panel display, a solid state display, etc.), and/or speakers. In the illustrated example, the infotainment head unit  160  includes hardware (e.g., a processor or controller, memory, storage, etc.) and software (e.g., an operating system, etc.) for an infotainment system (such as SYNC® and MyFord Touch® by Ford®, Entune® by Toyota®, IntelliLink® by GMC®, etc.). Additionally, the infotainment head unit  160  displays the infotainment system on, for example, the center console display. In some examples, the IHU  160  includes the internal speakers  134 . 
     In the examples of  FIGS. 1 and 2 , the mobile device  171  is a remote device. The mobile device  171  may be, for example, a smartphone a cellular telephone, a tablet, etc. The mobile device  171  includes a transceiver to send and receive messages from the transceiver  140 . In operation, during a remote-controlled auto-hitch maneuver, the mobile device  171  serves as a user interface for the driver  180  to control backward and/or forward movement of the vehicle  110 . More specifically, the OBCP  150  determines and controls steering of the vehicle  110  and the driver  180  controls the rotation speed and rotation direction of the wheels  112  via the mobile device  171 . As described above, in some examples, the driver  180  controls the rotation of the wheels  112  by commanding the wheels to either stop turning (e.g., zero rotation) or turn at a set predetermined value (e.g., 30 revolutions per minute, 50 revolutions per minute, etc.). In some examples, the rotation speed of the wheels  112  may be limited to a predetermined threshold during remote-controlled maneuvers. 
     In the examples of  FIGS. 1 and 2 , the key fob  172  is a remote device and includes a transceiver to send and receive messages from the transceiver  140 . In operation, during a remote-controlled auto-hitch maneuver, the key fob  172  serves as a localizing device for the OBCP  150  to determine a location of the driver  180  in relation to the vehicle  110 . More specifically, the OBCP  150  analyzes signals from the key fob  172  to determine a location of the key fob  172 . The OBCP  150  may analyze signals from the key fob  172  via, for example, time-of-flight analysis, low-frequency signal strength analysis, low-energy signal strength analysis, angle of arrival analysis, dead reckoning, etc. It should be understood that the method used for localization of the driver  180  in relation to the vehicle  110  will determine how precisely the driver  180  can be located (e.g., low-frequency signal strength analysis may be less precise than time-of-flight analysis). 
     In some examples, the key fob  172  is combined into the mobile device  171  (e.g., “phone-as-key”). It should therefore be understood that, in such examples, the vehicle  110  tracks the location of the driver  180  via the mobile device  171 . 
       FIG. 3  is a block diagram of electronic components  300  of the vehicle  110 .  FIG. 4  is a more detailed block diagram of the risk analyzer  340  of  FIG. 3 .  FIGS. 5-8  illustrate example travel zones  510 ,  610 ,  710 ,  810  defined by the risk analyzer  340 .  FIG. 9  is a look-up table  950  stored in a memory  320  of the electronic components  300 .  FIG. 10  illustrates the mobile device  171  used to remotely control the vehicle  110 . 
     As shown in  FIG. 3 , the first vehicle data bus  302  communicatively couples the sensors  120 , the horn  131 , the lights  132 , the windows  133 , the internal speakers  134 , the external speakers  135 , the puddle lamp  136 , the OBCP  150 , and other devices connected to the first vehicle data bus  302 . In some examples, the first vehicle data bus  302  is implemented in accordance with the controller area network (CAN) bus protocol as defined by International Standards Organization (ISO) 11898-1. Alternatively, in some examples, the first vehicle data bus  302  may be a Media Oriented Systems Transport (MOST) bus, a CAN flexible data (CAN-FD) bus (ISO 11898-7), or an Ethernet bus. The second vehicle data bus  304  communicatively couples the OBCP  150  the transceiver  140 , the IHU  160 , the mobile device  171 , and the key fob  172 . The second vehicle data bus  304  may be a MOST bus, a CAN bus, a CAN-FD bus, or an Ethernet bus. In some examples, the OBCP  150  communicatively isolates the first vehicle data bus  302  and the second vehicle data bus  304  (e.g., via firewalls, message brokers, etc.). Alternatively, in some examples, the first vehicle data bus  302  and the second vehicle data bus  304  are the same data bus. 
     The OBCP  150  includes a processor or controller  310  and memory  320 . In the illustrated example, the OBCP  150  is structured to include a trailer detector  330  and the risk analyzer  340 . Alternatively, in some examples, the trailer detector  330  and the risk analyzer  340  may be incorporated into another electronic control unit (ECU) with its own processor  310  and memory  320 . 
     In operation, the trailer detector  330  locates the hitch coupler  191  of the trailer  190  and determines a path for the vehicle  110  to follow to move the towing ball  113  into place for coupling with the hitch coupler  191  based on obstruction information from the sensors  120 . The trailer detector  330  communicates with the steering of the vehicle  110  to turn the wheels of the vehicle  110  toward the detected hitch coupler  191  of the trailer  190 . The trailer detector  330  communicatively connects the powertrain of the vehicle  110  with the mobile device  171 . Thus, the mobile device  171  may remotely control the rotational speed and direction of the wheels of vehicle  110 . 
     In operation, the risk analyzer  340  defines travel zones  510 ,  610 ,  710 ,  810 , locates the key fob  172 , determines whether the key fob  172  is in range for remote control, determines whether the key fob  172  is inside the vehicle  110 , determines whether the key fob  172  is in a travel zone  510 ,  610 ,  710 ,  810 , estimates a trajectory of the driver  180  holding the key fob  172 , determines a risk assessment of whether the vehicle  110  will contact the driver  180 , and determines whether to present warnings to the driver  180  and/or stop the vehicle  110 . The risk analyzer  340  makes these determinations and estimations based on obstruction information from the sensors  120  and signals from the key fob  172 . 
     The processor or controller  310  may be any suitable processing device or set of processing devices such as, but not limited to: a microprocessor, a microcontroller-based platform, a suitable integrated circuit, one or more field programmable gate arrays (FPGAs), and/or one or more application-specific integrated circuits (ASICs). The memory  320  may be volatile memory (e.g., RAM, which can include non-volatile RAM, magnetic RAM, ferroelectric RAM, and any other suitable forms); non-volatile memory (e.g., disk memory, FLASH memory, EPROMs, EEPROMs, non-volatile solid-state memory, etc.), unalterable memory (e.g., EPROMs), read-only memory, and/or high-capacity storage devices (e.g., hard drives, solid state drives, etc.). In some examples, the memory  320  includes multiple kinds of memory, particularly volatile memory and non-volatile memory. 
     The memory  320  is computer readable media on which one or more sets of instructions, such as the software for operating the methods of the present disclosure can be embedded. The instructions may embody one or more of the methods or logic as described herein. In a particular embodiment, the instructions may reside completely, or at least partially, within any one or more of the memory  320 , the computer readable medium, and/or within the processor  310  during execution of the instructions. The memory  320  stores threshold data  350  and zone data  360 . 
     In some examples, the threshold data  350  includes the look up table  950 . As shown in  FIG. 9 , the look up table  950  corresponds estimated contact time values  951  to risk assessment values  952  and to warnings  953  for the vehicle  110 . In other words, the look up table  950  provides predetermined risk assessments  952  and corresponding warnings  953  for a given estimated contact time  951 . As shown in the examples of  FIG. 9 , as the estimated contact times  951  decrease, the corresponding risk assessment values  952  increase and the disruptiveness of the warnings  953  increase. As shown in the example of  FIG. 9 , an estimated contact time of 25 seconds or less, but more than 20 seconds corresponds to a 0.30 risk assessment value  952  for which the vehicle  110  may flash the lights  132 . As shown in the example of  FIG. 9 , an estimated contact time of 5 seconds or less corresponds to a 0.90 risk assessment value  952  for which the vehicle  110  may stop moving. In some examples, for a given risk assessment value  952 , the vehicle  110  may generate the corresponding warning  953  and any of the preceding warnings  953 . Thus, in such examples, for the 0.90 risk assessment value  952 , the vehicle  110  may stop, flash the lights  132 , chirp the horn  131 , and/or blast the horn  131 . Blasting the horn  131  refers to sounding the horn  131  for an extended period (e.g., 1 or more seconds, etc.).  FIG. 6  shows additional examples of estimated contact time, risk assessment value, and warning correspondences. It should be understood and appreciated that the look up table  950  depicted in  FIG. 9  is an abridged example and that a look up table stored in the memory  320  may include additional estimated contact times, risk assessment values, and warnings. It should also be understood that the look up table  950  may be updated when the vehicle  110  is serviced and/or during routine Over-the-Air (OTA) updates. Updates to the look up table  950  may be performed via the transceiver  140 , the IHU  160 , and/or an on board diagnostics (OBD) port of the vehicle  110 . 
     The terms “non-transitory computer-readable medium” and “tangible computer-readable medium” should be understood to include a single medium or multiple media, such as a centralized or distributed database, and/or associated caches and servers that store one or more sets of instructions. The terms “non-transitory computer-readable medium” and “tangible computer-readable medium” also include any tangible medium that is capable of storing, encoding or carrying a set of instructions for execution by a processor or that cause a system to perform any one or more of the methods or operations disclosed herein. As used herein, the term “tangible computer readable medium” is expressly defined to include any type of computer readable storage device and/or storage disk and to exclude propagating signals. 
     As shown in  FIG. 4 , the risk analyzer  340  includes a data receiver  410 , a zone determiner  420 , a location determiner  430 , a trajectory estimator  440 , a contact time determiner  450 , an assessment threshold comparator  460 , and a feedback generator  470 . 
     In operation, the data receiver  410  receives obstruction information sent by the sensors  120 , signals from the mobile device  171 , and signals from the key fob  172 . More specifically, the data receiver  410  receives images, reflections, and echoes of obstructions behind the vehicle  110  captured by the sensors  120 . Additionally, the data receiver  410  receives strengths, arrival times, and arrival angles of the signals from the mobile device  171  and the key fob  172 . 
     In operation, the zone determiner  420  defines a travel zone of the vehicle  110  out of which the driver  180  and other pedestrian are to stay. More specifically, the zone determiner  420  accesses the zone data  360  stored in the memory  320 . The zone determiner  420  applies a predetermined travel zone to the vehicle  110  and/or the trailer  190  based on the zone data  360 . In some examples, the travel zone has a minimum size. In some examples, the travel zone increases in size as the speed of the vehicle  110  increases and vice versa. 
     In some embodiments, the travel zone  510  is defined as an area through which the vehicle  110  passes while approaching the trailer  190 , as shown in  FIG. 5 . More specifically, the trailer detector  330  detects the trailer  190  and determines a path  505  for the vehicle  110  to follow to approach the vehicle  110  to the hitch coupler  191 . In this embodiment, the travel zone  510  covers locations through which the vehicle  110  will pass while following the path  505 . Thus, in this embodiment, the travel zone  510  decreases in area as the vehicle  110  moves toward the trailer  190 . 
     In some embodiments, the travel zone  610  is defined as an area within a specified radius r around the hitch coupler  191 , as shown in  FIG. 6 . Thus, in this embodiment, the travel zone  610  is static. 
     Additionally, in some embodiments, the zone determiner  420  defines a control zone that the driver  180  must remain within to remotely control the vehicle  110 . More specifically, the zone determiner  420  applies a predetermined control zone to the vehicle  110  based on the zone data  360  accessed from the memory  320 . In some embodiments, the control zone  720  is an area within a predetermined distance (e.g., six meters, etc.) of the outermost portions of the vehicle  110 , as shown in  FIGS. 7 and 8 . The outermost portions of the vehicle  110  are sometimes referred to as the skin of the vehicle  110 . 
     In some embodiments, the travel zone  710  is defined as an area immediately behind the vehicle  110  and within the control zone  720 , as shown in  FIG. 7 . Thus, in this embodiment, the travel zone  710  travels with the vehicle  110 . 
     In some embodiments, the travel zone  810  is defined as an intersection of the control zone  720  about the vehicle  110  and an area within a specified radius r around the hitch coupler  191 , as shown in  FIG. 8 . In other words, in such embodiments, the travel zone  810  is an area where the control zone  720  overlaps the radius r about the hitch coupler  191 . Thus, the travel zone  810  increases in size as the vehicle  110  approaches the hitch coupler  191  and vice versa. 
     In operation, the location determiner  430  determines whether the driver  180  is within the defined travel zone and/or control zone. More specifically, the location determiner  430  analyzes signals from the key fob  172  to determine a location of the key fob  172  relative to the vehicle  110 . In other words, the location determiner  430  localizes the key fob  172  to determine a location of the driver  180 . Methods by which the location determiner  430  localizes the key fob  172  include, for example, time-of-flight analysis, signal strength analysis, angle of arrival analysis, dead reckoning, etc. 
     In some embodiments, once the location of the key fob  172  is determined, the location determiner  430  determines whether the key fob  172  is within the range of the control zone  720 . In other words, the location determiner  430  compares the location of the key fob  172  to the defined control zone  720 . In some embodiments, if the key fob  172  is outside of the control zone  720 , the location determiner  430  pauses the remote-controlled vehicle maneuver. In some embodiments, if the key fob  172  is inside the vehicle  110 , the location determiner  430  pauses the remote-controlled vehicle maneuver. Pausing the remote-controlled vehicle maneuver includes communicating with the powertrain of the vehicle  110  to stop the vehicle  110  and/or canceling the maneuver. 
     Further, the location determiner  430  determines whether the key fob  172  is within the travel zone. In other words, the location determiner  430  compares the location of the key fob  172  to the defined travel zone. It should be understood that the location determiner  430  searches for the key fob  172  repeatedly. In other words, the location determiner  430  analyzes the signals from the key fob  172  and determines the location of the key fob  172  according to a predetermined sample rate (e.g., 8 samples per second, 10 samples per second, 16 samples per second, etc.). Thus, the location determiner  430  updates the location of the key fob  172  when the driver  180  moves relative to the vehicle  110 . 
     In operation, the trajectory estimator  440  estimates a trajectory of the driver  180  as the driver  180  moves relative to the vehicle  110 . More specifically, the trajectory estimator  440  estimates a speed and direction at which the driver  180  is walking relative to the vehicle  110  based on the updated key fob  172  locations from the location determiner  430 . 
     In operation, the contact time determiner  450  estimates when the vehicle  110  would hypothetically contact the driver  180  if the vehicle  110  continued to approach the trailer  190  and the driver  180  remained in the travel zone. More specifically, the contact time determiner  450  determines a closing speed at which the driver  180  and the vehicle  110  approach one another based on the estimated trajectory of the driver  180  from the trajectory estimator  440  and the speed at which the vehicle  110  approaches the trailer  190 . Further, the contact time determiner  450  estimates a time period remaining until the vehicle  110  would hypothetically reach the driver  180  based on the closing speed. This remaining time period may be referred to as an estimated contact time. In other words, the contact time determiner  450  estimates how much time remains for the driver  180  move away from the vehicle  110  before hypothetically contacting the vehicle  110 . It should be understood that the risk analyzer  340  is configured to stop the vehicle  110  before the vehicle  110  contacts the driver  180 , as will be explained in greater detail below. 
     In operation, the assessment threshold comparator  460  selects a predetermined risk assessment value based on the estimated contact time from the contact time determiner  450 . More specifically, the assessment threshold comparator  460  accesses the threshold data  350  (e.g., the look up table  950 ) stored in the memory  320 . The assessment threshold comparator  460  compares the estimated contact time to threshold data  350  and selects the corresponding risk assessment value. Further, the assessment threshold comparator  460  selects the warning corresponding to the selected risk assessment value from the threshold data  350 . In some embodiments, the assessment threshold comparator  460  additionally selects any other warnings corresponding to risk assessments having values lower than the selected risk assessment value. 
     In operation the feedback generator  470  generates feedback based on the selected warnings from the assessment threshold comparator  460 . More specifically, the feedback generator  470  generates audio messages and/or visual messages warning a driver  180  of the approaching vehicle  110 . Further, the feedback generator  470  sends the messages for display via the IHU  160 , the lights  132 , and/or the puddle lamp  136  and/or for announcement via the speakers  134 ,  135  and/or the horn  131 . Additionally, the feedback generator  470  communicates with the powertrain of the vehicle  110  to slow or stop the vehicle  110 . 
     Also, as shown in  FIG. 10 , the feedback generator  470  communicates warnings to the mobile device  171 . More specifically, the feedback generator  470  sends messages  1010  and/or illustrations  1020  for display to the driver  180  via a display  173  of the mobile device  171 . The message  1010  may include a text description of the status of the remote-control hitching process, a warning to exit the travel zone, and/or instructions to avoid contact with the vehicle  110 . The illustration  1020  may depict the vehicle  110  and the driver  180  in the travel zone. 
       FIG. 11  is a flowchart of a method  1100  to prevent contact between the vehicle  110  and the driver  180  of  FIG. 1  during a remote-controlled maneuver, which may be implemented by the electronic components  300  of  FIG. 3 . The flowchart of  FIG. 11  is representative of machine readable instructions stored in memory (such as the memory  320  of  FIG. 3 ) that comprise one or more programs that, when executed by a processor (such as the processor  310  of  FIG. 3 ), cause the vehicle  110  to implement the example trailer detector  330  and risk analyzer  340  of  FIGS. 3 and 4 . Further, although the example program(s) is/are described with reference to the flowchart illustrated in  FIG. 11 , many other methods of implementing the example risk analyzer  340  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. 
     Initially, at block  1102 , the trailer detector  330  determines a path for the vehicle  110  to follow to approach the trailer  190 . As discussed above, the trailer detector  330  determines the path based on obstruction information from the sensors  120 . 
     At block  1104 , the zone determiner  420  defines a travel zone and, in some embodiments, a control zone related to the vehicle  110 . More specifically, the zone determiner  420  accesses the zone data  360  stored in the memory  320  and applies a predetermined travel zone (e.g., one of the travel zones  510 ,  610 ,  710 ,  810 ) and a predetermined control zones (e.g., control zone  720 ) to the vehicle  110 , as discussed above. 
     At block  1106 , the location determiner  430  localizes the key fob  172 . More specifically, the location determiner  430  analyzes wireless signals from the key fob  172  to determine a location of the key fob  172  relative to the vehicle  110 , as discussed above. 
     At block  1108 , the location determiner  430  determines whether the key fob  172  is in range. More specifically, the location determiner  430  compares the location of the key fob  172  to the defined the control zone  720 , as discussed above. 
     If, at block  1108 , the location determiner  430  determines that the key fob  172  is in range, the method  1100  proceeds to block  1110 . 
     If, at block  1108 , the location determiner  430  determines that the key fob  172  is out of range, the method  1100  proceeds to block  1130 . 
     At block  1130 , the location determiner  430  pauses the remote-controlled vehicle maneuver. More specifically, the location determiner  430  communicates with the powertrain of the vehicle  110  to stop the vehicle  110  and/or cancels the maneuver, as discussed above. The method  1100  then returns to block  1102 . 
     At block  1110 , the location determiner  430  determines whether the key fob  172  is in the vehicle  110 , as discussed above. 
     If, at block  1110 , the location determiner  430  determines that the key fob  172  is in the vehicle  110 , the method  1100  proceeds to block  1130 . 
     If, at block  1110 , the location determiner  430  determines that the key fob  172  is out of the vehicle  110 , the method  1100  proceeds to block  1112 . 
     At block  1112 , the location determiner  430  determines whether the key fob  172  is within the travel zone. More specifically, the location determiner  430  compares the location of the key fob  172  to the defined travel zone, as discussed above. 
     If, at block  1112 , the location determiner  430  determines that the key fob  172  is not inside (i.e., outside) the travel zone, the method  1100  proceeds to block  1128 . 
     If, at block  1112 , the location determiner  430  determines that the key fob  172  is inside the travel zone, the method  1100  proceeds to block  1114 . 
     At block  1114 , the trajectory estimator  440  estimates a trajectory of the driver  180 . More specifically, the trajectory estimator  440  estimates a speed and direction of the driver  180  holding the key fob  172  relative to the vehicle  110 , as discussed above. The method  1100  proceeds to block  1116 . 
     At block  1116 , the contact time determiner  450  produces a contact time estimate of when the vehicle  110  will hypothetically contact the driver  180 . More specifically, the contact time determiner  450  determines hypothetically how much time remains until the vehicle  110  contacts the driver  180  if the vehicle  110  were to continue approaching the trailer  190  and the driver  180  were to continue on his or her trajectory, as discussed above. The method  1100  proceeds to block  1118 . 
     At block  1118 , the assessment threshold comparator  460  compares the contact time estimate to predetermined risk assessment thresholds and corresponding warnings. More specifically, the assessment threshold comparator  460  accesses the threshold data  350  stored in the memory  320  and selects a risk assessment value according to the contact time estimate, as discussed above. The method  1100  proceeds to block  1120 . 
     At block  1120 , the assessment threshold comparator  460  determines whether to stop the vehicle  110  based on the selected risk assessment value. More specifically, the assessment threshold comparator  460  determines whether the warning corresponding to the selected risk assessment value includes stopping the vehicle  110 , as discussed above. 
     If, at block  1120 , the assessment threshold comparator  460  determines that the warning corresponding to the selected risk assessment value includes stopping the vehicle  110 , the method  1100  proceeds to block  1122 . 
     At block  1122 , the feedback generator  470  stops the vehicle  110 . More specifically, the feedback generator  470  communicates with the powertrain of the vehicle  110  to stop approaching the trailer  190 , as discussed above. The method  1100  proceeds to block  1124 . 
     At block  1124 , the feedback generator  470  relays messages to the driver  180  that the remote-control maneuver is stopped. More specifically, the feedback generator  470  announces audio messages and/or displays visual messages via the vehicle  110  and/or the mobile device  171 , as discussed above. The method  1100  then returns to block  1102 . 
     If, at block  1120 , the assessment threshold comparator  460  determines that the warning corresponding to the selected risk assessment value does not include stopping the vehicle  110 , the method  1100  proceeds to block  1126 . 
     At block  1126 , the feedback generator  470  relays messages to the driver  180  that the driver  180  is the travel zone and/or instructing the driver  180  to move away from the vehicle  110 . More specifically, the feedback generator  470  announces audio messages and/or displays visual messages via the vehicle  110  and/or the mobile device  171 , as discussed above. The method  1100  then proceeds to block  1128 . 
     At block  1128 , the trailer detector  330  moves the vehicle  110  toward the hitch coupler  191  of the trailer  190 . More specifically, the trailer detector  330  communicates with the steering and powertrain of the vehicle  110  and the mobile device  171  to guide the vehicle  110  via remote control, as discussed. The method  1100  then returns to block  1102 . 
     In this application, the use of the disjunctive is intended to include the conjunctive. The use of definite or indefinite articles is not intended to indicate cardinality. In particular, a reference to “the” object or “a” and “an” object is intended to denote also one of a possible plurality of such objects. Further, the conjunction “or” may be used to convey features that are simultaneously present instead of mutually exclusive alternatives. In other words, the conjunction “or” should be understood to include “and/or”. The terms “includes,” “including,” and “include” are inclusive and have the same scope as “comprises,” “comprising,” and “comprise” respectively. 
     From the foregoing, it should be appreciated that the above disclosed apparatus and methods may aid drivers by allowing drivers to remotely control their vehicle maneuvers while preventing contact between the driver and the vehicle. By allowing drivers to remotely control their vehicles, drivers may more closely observe the vehicle maneuver. In instances where the vehicle maneuver is assisted guidance toward a trailer hitch, the driver may observe whether the trailer hitch matches a vehicle towing in height. Thus, remote control of the assisted trailer guidance may prevent repetition of the trailer-hitching process, thereby saving time and associated fuel. Additionally, warning drivers of the approaching remote-controlled vehicle may remind drivers to be vigilant while performing vehicle maneuvers via remote control. It should also be appreciated that the disclosed apparatus and methods provide a specific solution—warning drivers of approaching remote-controlled vehicles—to a specific problem—potential contact between drivers, vehicles, and/or trailers during remote-controlled maneuvers. Further, the disclosed apparatus and methods provide an improvement to computer-related technology by increasing functionality of a processor to define travel and/or control zones related to a vehicle, determine a location of a driver outside of the vehicle, determine a trajectory of the driver, estimate a time remaining until a potential contact between the driver and the vehicle, select a risk assessment based on the estimated contact time, and generate warnings based on the risk assessment. 
     As used here, the terms “module” and “unit” refer to hardware with circuitry to provide communication, control and/or monitoring capabilities, often in conjunction with sensors. “Modules” and “units” may also include firmware that executes on the circuitry. 
     The above-described embodiments, and particularly any “preferred” embodiments, are possible examples of implementations and merely set forth for a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiment(s) without substantially departing from the spirit and principles of the techniques described herein. All modifications are intended to be included herein within the scope of this disclosure and protected by the following claims.