Patent Publication Number: US-10774574-B2

Title: Operation of vehicle power doors

Description:
BACKGROUND 
     Vehicle closure systems may use a Hall Effect sensor mounted to a vehicle and associated outputs of the Hall Effect sensor to control a drive motor closing a door of the vehicle. In this regard, the Hall Effect sensor may be utilized to determine a speed or position of the door relative to a position of a body of the vehicle. However, Hall Effect sensors may be associated with drift and thus, require compensation. Further, if power is lost during the door closing operation, recalibration of the Hall Effect sensor may be required. 
     BRIEF DESCRIPTION 
     According to one aspect, a system for vehicle power door operation may include a first accelerometer, a second accelerometer, a motor controller, and an electronic control unit (ECU). The first accelerometer may be mounted to a first portion of a vehicle. The second accelerometer may be mounted to a second portion of the vehicle. The motor controller may control a power operation of a door of the vehicle. The ECU may receive a first measurement from the first accelerometer, receive a second measurement from the second accelerometer, determine an orientation of the vehicle relative to a reference plane based on the first measurement and the second measurement, and adjust the power operation of the power door by the motor controller based on the determined orientation. 
     The first measurement or the second measurement may include a proper acceleration measurement or a coordinate acceleration measurement. The first accelerometer may be mounted to a vehicle body of the vehicle, the second accelerometer may be mounted to a power door of the vehicle, and the motor controller may control a power operation of the power door of the vehicle. The first accelerometer may be integrated with the ECU. The first accelerometer and the second accelerometer may be 2-axis or 3-axis accelerometers. Adjusting the power operation of the power door by the motor controller may include reversing a direction of the power operation of the power door or stopping operation of the power door. The system may include a bus operably connecting the first accelerometer, the second accelerometer, the motor controller, and the ECU. The ECU may determine any movement of the vehicle relative to the reference plane based on the first measurement and the second measurement and adjust the power operation of the power door by the motor controller based on the determined movement. 
     According to one aspect, a system for vehicle power door operation may include a first accelerometer, a second accelerometer, a motor controller, and an electronic control unit (ECU). The first accelerometer may be mounted to a first portion of a vehicle. The second accelerometer may be mounted to a second portion of the vehicle. The motor controller may control a power operation of a door of the vehicle. The ECU may receive a first measurement from the first accelerometer, receive a second measurement from the second accelerometer, determine any movement of the vehicle relative to a reference plane based on the first measurement and the second measurement, and adjust the power operation of the power door by the motor controller based on the determined movement. 
     The first measurement or the second measurement may include a proper acceleration measurement or a coordinate acceleration measurement. The first accelerometer may be mounted to a vehicle body of the vehicle, the second accelerometer may be mounted to a power door of the vehicle, and the motor controller may control a power operation of the power door of the vehicle. The first accelerometer may be integrated with the ECU. The first accelerometer and the second accelerometer may be 2-axis or 3-axis accelerometers. Adjusting the power operation of the power door by the motor controller may include reversing a direction of the power operation of the power door or stopping operation of the power door. The system may include a bus operably connecting the first accelerometer, the second accelerometer, the motor controller, and the ECU. The ECU may determine an orientation of the vehicle relative to the reference plane based on the first measurement and the second measurement and adjust the power operation of the power door by the motor controller based on the determined orientation. 
     According to one aspect, a system for vehicle power door operation may include a first accelerometer, a second accelerometer, a motor controller, and an electronic control unit (ECU). The first accelerometer may be mounted to a first portion of a vehicle. The second accelerometer may be mounted to a second portion of the vehicle. The motor controller may control a power operation of a door of the vehicle. The ECU may receive a first measurement from the first accelerometer, receive a second measurement from the second accelerometer, determine an orientation of the vehicle relative to a reference plane based on the first measurement and the second measurement, determine any movement of the vehicle relative to the reference plane based on the first measurement and the second measurement, and adjust the power operation of the power door by the motor controller based on the determined orientation and the determined movement. 
     The first measurement or the second measurement may include a proper acceleration measurement or a coordinate acceleration measurement. The first accelerometer may be mounted to a vehicle body of the vehicle, the second accelerometer may be mounted to a power door of the vehicle, and the motor controller may control a power operation of the power door of the vehicle. The first accelerometer and the second accelerometer may be 2-axis or 3-axis accelerometers. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an illustration of an exemplary system for vehicle power door operation, according to one aspect. 
         FIG. 2  is an illustration of an exemplary system for vehicle power door operation, according to one aspect. 
         FIG. 3  is an illustration of an exemplary system for vehicle power door operation, according to one aspect. 
         FIG. 4  is an illustration of an exemplary system for vehicle power door operation, according to one aspect. 
         FIG. 5  is an illustration of an exemplary system for vehicle power door operation, according to one aspect. 
         FIG. 6  is an illustration of an example component diagram of the system for vehicle power door operation, according to one aspect. 
         FIG. 7  is an illustration of an example flow diagram of a method for vehicle power door operation, according to one aspect. 
         FIG. 8  is an illustration of an example computer-readable medium or computer-readable device including processor-executable instructions configured to embody one or more of the provisions set forth herein, according to one aspect. 
         FIG. 9  is an illustration of an example computing environment where one or more of the provisions set forth herein are implemented, according to one aspect. 
     
    
    
     DETAILED DESCRIPTION 
     The following terms are used throughout the disclosure, the definitions of which are provided herein to assist in understanding one or more aspects of the disclosure. 
     “Vehicle”, as used herein, refers to any moving vehicle that is capable of carrying one or more human occupants and is powered by any form of energy. In some cases, a motor vehicle includes one or more engines. The term “vehicle” may also refer to an autonomous vehicle and/or self-driving vehicle powered by any form of energy. The vehicle may carry one or more human occupants or other cargo. Further, the term “vehicle” may include vehicles that are automated or non-automated with pre-determined paths or free-moving vehicles. 
     “Module”, as used herein, includes, but is not limited to, a non-transitory computer readable medium that stores instructions, instructions in execution on a machine, hardware, firmware, software in execution on a machine, and/or combinations of each to perform a function(s) or an action(s), and/or to cause a function or action from another module, method, and/or system. A module may include logic, a software controlled microprocessor, a discrete logic circuit, an analog circuit, a digital circuit, a programmed logic device, a memory device containing executing or executable instructions, logic gates, a combination of gates, and/or other circuit components, such as the modules, systems, devices, units, or any of the components of  FIG. 1 . Multiple modules may be combined into one module and single modules may be distributed among multiple modules. 
     “Bus”, as used herein, refers to an interconnected architecture that is operably connected to other computer components inside a computer or between computers. The bus may transfer data between the computer components. The bus may be a memory bus, a memory processor, a peripheral bus, an external bus, a crossbar switch, and/or a local bus, among others. The bus may also be a vehicle bus that interconnects components inside a vehicle using protocols such as Media Oriented Systems Transport (MOST), Controller Area Network (CAN), Local Interconnect network (LIN), among others. 
     “Communication”, as used herein, refers to a communication between two or more computing devices (e.g., computer, personal digital assistant, cellular telephone, network device) and/or components and may be, for example, a network transfer, a file transfer, an applet transfer, an email, a hypertext transfer protocol (HTTP) transfer, and so on. A computer communication may occur across, for example, a wireless system (e.g., IEEE 802.11), an Ethernet system (e.g., IEEE 802.3), a token ring system (e.g., IEEE 802.5), a local area network (LAN), a wide area network (WAN), a point-to-point system, a circuit switching system, a packet switching system, among others. 
     “Operable connection”, as used herein, or a connection by which entities are “operably connected”, is one in which signals, physical communications, and/or logical communications may be sent and/or received. An operable connection may include a wireless interface, a physical interface, a data interface, and/or an electrical interface. For example, one or more of the components of  FIG. 1  may be operably connected with one another, thereby facilitating communication therebetween. 
     “Infer” or “inference”, as used herein, generally refers to the process of reasoning about or inferring states of a system, a component, an environment, a user from one or more observations captured via events or data, etc. Inference may be employed to identify a context or an action or may be employed to generate a probability distribution over states, for example. An inference may be probabilistic. For example, computation of a probability distribution over states of interest based on a consideration of data or events. Inference may also refer to techniques employed for composing higher-level events from a set of events or data. Such inference may result in the construction of new events or new actions from a set of observed events or stored event data, whether or not the events are correlated in close temporal proximity, and whether the events and data come from one or several event and data sources. 
       FIG. 1  is an illustration of an exemplary system  100  for vehicle power door operation, according to one aspect. The system  100  for vehicle power door operation may be implemented on a vehicle to facilitate anti-entrapment for one or more doors of the vehicle during vehicle power door operations, such as power opening or power closing of respective doors. As used herein, a door (e.g., power door) is used interchangeably with a tailgate, a power tailgate  120 , or a power trunk. In other words, although some examples may be described with reference to a power door or the power tailgate  120 , it is understood that these embodiments may be implemented with respect to either. Additionally, the system  100  for vehicle power door operation may provide adjustments during vehicle power door operations. 
     According to one aspect, the system  100  for vehicle power door operation may include an electronic control unit (ECU)  110  which includes a first accelerometer  112 . Stated another way, according to this aspect, the first accelerometer  112  may be integrated with the ECU  110 . It will be appreciated that, according to other aspects, the first accelerometer  112  may be mounted at other locations or positions on a vehicle body  102  of the vehicle. In any event, in  FIG. 1 , the power tailgate  120  of the vehicle may have a second accelerometer  122  mounted thereto. A motor controller  130  may be utilized to open and close the power tailgate  120 . As a result of the opening and closing of the power tailgate  120 , the second accelerometer  122  may travel along a path  150 . In  FIG. 1 , the path  150  of the second accelerometer  122  is generally downwards, in the same direction as gravity, but in other scenarios, such as the scenario as will be described with reference to  FIG. 3  herein, the path  150  of the second accelerometer  122  may include an upward portion or component, in the opposite direction as gravity. 
     The first accelerometer  112  and the second accelerometer  122  may be 2-axis, multi-axis accelerometers, or 3-axis accelerometers which detect a magnitude and a direction of acceleration. In this regard, the first accelerometer  112  and the second accelerometer  122  may provide measurements as proper acceleration or as coordinate acceleration. The first accelerometer  112  may be mounted to a first portion of the vehicle while the second accelerometer  122  may be mounted to a second portion of the vehicle. The first accelerometer  112  may provide a first measurement to the ECU  110  and the second accelerometer  122  may provide a second measurement to the ECU  110 . These first and second measurements may include a proper acceleration measurement or a coordinate acceleration measurement, measurements relating to an orientation of the corresponding accelerometer with respect to gravity, movement associated with the corresponding accelerometer, etc. 
     Using these first and second measurements, the ECU  110  may calculate a position, an orientation, a velocity, an angle associated with the power tailgate  120  opening with respect to gravity, or other movement of the vehicle without any other external references. In other words, using the first and second measurements from the first accelerometer  112  and the second accelerometer  122 , respectively, the ECU  110  may determine (e.g., via a comparison of the first and second measurements) an orientation of the vehicle relative to a reference plane  160  or any movement associated with the vehicle relative to the reference plane  160 . Stated yet another way, the ECU  110  may determine the orientation of the vehicle relative to the reference plane  160  based on the first measurement and the second measurement (as will be described with reference to  FIGS. 3-4 ) and determine any (e.g., associated) movement of the vehicle (as will be described with reference to  FIG. 5 ) relative to the reference plane  160  based on the first measurement and the second measurement (e.g., via the comparison of respective measurements). 
       FIG. 2  is an illustration of an exemplary system  100  for vehicle power door operation, according to one aspect. In  FIG. 2 , a third accelerometer  212  may be mounted to a third portion of the vehicle (e.g., a rear portion of the vehicle body  102 ). Similarly to the first accelerometer  112  and the second accelerometer  122 , the third accelerometer  212  may also provide a measurement of proper acceleration or coordinate acceleration. Because the vehicle is parked on a flat ground plane, the third accelerometer  212  may register a reading of 9.81 m/s 2  while the vehicle is at rest, due to the Earth&#39;s gravity (e.g., which may be used as another reference plane  250 ), for example. Additionally, these measurements, the ECU  110  may calculate an angle  270  associated with the power tailgate  120  opening with respect to gravity  250  (without using any external references). 
       FIG. 3  is an illustration of an exemplary system  100  for vehicle power door operation, according to one aspect. In  FIG. 3 , the vehicle is parked facing uphill on an incline  310 . In other words, the vehicle is parked such that the first accelerometer  112  is located farther up the incline  310  than the second accelerometer  122  and the third accelerometer  212 . As a result of this parking configuration, the third accelerometer  212  is located on a downhill side of the incline  310  and this orientation may be recognized by the ECU  110  based on an analysis of the first and second measurements. Further, the second accelerometer  122 , during a power closing operation, may travel along a first portion  320  of the path and a second portion  330  of the path. 
     It will be appreciated that the first portion  320  of the path is associated with a vector component which is in the same direction as gravity  250 , while the second portion  330  of the path is associated with a vector component which is in the opposite direction as gravity  250 . In this regard, the ECU  110  may receive measurements (e.g., the first measurement, the second measurement, and/or the third measurement, etc.) from the first accelerometer  112 , the second accelerometer  122 , and/or the third accelerometer  212 , respectively, and determine an orientation of the vehicle relative to the reference plane  160  based on the respective measurements. While this example is described with respect to the first accelerometer  112 , the second accelerometer  122 , and the third accelerometer  212 , it will be appreciated that fewer (e.g., two) or more accelerometers may be implemented according to other aspects. 
     In any event, the ECU  110  may determine the orientation of the vehicle relative to the reference plane  160 , and in this example, determine that the vehicle is facing uphill on the incline  310 . Further, the second accelerometer  122  may continually provide updated second measurements throughout a power tailgate  120  closure operation from the first portion  320  of the path to the second portion  330  of the path. As previously discussed, along the first portion  320  of the path, the second accelerometer  122  may merely provide second measurements indicative of a downward component in the same direction as gravity  250 . However, at a transition point  350  between the first portion  320  of the path and the second portion  330  of the path, the second accelerometer  122  may provide second, updated measurements indicative of an upward component in the opposite direction as gravity  250 . 
     In this regard, the ECU  110  may adjust the power operation of the power tailgate  120  by the motor controller  130  based on this newly determined orientation of the power tailgate  120  and associated second accelerometer  122  (e.g., due to the change between the vertical movement component associated with the first portion  320  of the path and the second portion  330  of the path). For example, along the first portion  320  of the path, the ECU  110  may adjust the power operation of the power tailgate  120  by commanding the motor controller  130  to increase torque in a first direction (e.g., a counterclockwise direction in  FIG. 3 ). 
     According to one aspect, the ECU  110  may adjust the power operation of the power tailgate  120  by the motor controller  130  based on the determined orientation of the vehicle, the angle  270  associated with the power tailgate  120  opening with respect to gravity  250 , an angle  370  of the incline  310 , and/or a weight associated with the power tailgate  120  structure. Along the second portion  330  of the path, the ECU  110  may adjust the power operation of the power tailgate  120  by commanding the motor controller  130  to increase torque in a second direction (e.g., a clockwise direction in  FIG. 3 ) which is opposite of the first direction. In this way, safety may be enhanced during vehicle power door operation. 
     According to other aspects, the ECU  110  may calculate an angle  370  associated with the incline  310  and/or the transition point  350  between the first portion  320  of the path and the second portion  330  of the path. In this regard, if the second accelerometer  122  senses an unexpected measurement event (e.g., a vibration exceeding a threshold, a sudden change in acceleration, etc.), the ECU  110  may implement an anti-entrapment measure and adjust the power operation of the power tailgate  120  by the motor controller  130  by reversing a direction of the power operation of the power tailgate  120  or stopping operation of the power tailgate  120  or power door. 
     In any event, with the first accelerometer  112  mounted on the first portion of the vehicle and the second accelerometer  122  mounted to the second portion of the vehicle (e.g., different than the first portion or separate and away from the first portion), the ECU  110  may determine the position of the power tailgate  120  by comparing the first measurement (e.g., an absolute measurement indicative of the position of the vehicle body  102 ) and the second measurement (e.g., an absolute measurement indicative of the position of the power tailgate  120 ), thereby producing a relative measurement indicative of the position of the power tailgate  120  relative to the vehicle body  102  and/or trunk latch. 
       FIG. 4  is an illustration of an exemplary system  100  for vehicle power door operation, according to one aspect. In  FIG. 4 , the vehicle is parked facing downhill, rather than facing uphill, and the ECU  110  may make an orientation determination accordingly based on the first and second measurements from the respective first accelerometer  112  and the second accelerometer  122 . Here, during the power tailgate  120  closing operation, the second accelerometer  122  may travel along a path  420  which is associated with the downward component of gravity  250  along the entire path  420 . In this regard, the ECU  110  may command the motor controller  130  to adjust the power operation of the power tailgate  120  to increase torque (in the clockwise direction in  FIG. 4 ) based on the determined orientation of the vehicle. 
       FIG. 5  is an illustration of an exemplary system  100  for vehicle power door operation, according to one aspect. In this example, an individual  502  is getting out of the vehicle, thereby causing the vehicle, including the first accelerometer  112  and the second accelerometer  122  (and the third accelerometer  212 , if used) to move  510  in a vertical direction. Because the first accelerometer  112  and the second accelerometer  122  may provide first and second measurements indicative of this vertical movement  510 , the ECU  110  may adjust the power operation of the power tailgate  120  by commanding the motor controller  130  accordingly. 
     According to another aspect, if another individual  522  is blocking the path of the power tailgate  120 , when the power tailgate  120  contacts  530  the individual at that portion of the path, the first accelerometer  112  and the second accelerometer  122  may provide first and second measurements associated with different characteristics than when movement  510  occurs (e.g., opposite polarity with respect to gravity  250 ) or signatures than when the individual is getting out of the vehicle (e.g., sharing the same polarity vertical component). For example, the ECU  110  may determine, from the first measurement and the second measurement, that the movement of the vehicle is primarily localized to an area near the second accelerometer  122 . This may be taken as an inference that the individual  522  is blocking, at  530 , the power tailgate  120  from closing. In this regard, the ECU  110  may enable anti-entrapment measures to be implemented by the motor controller  130 , such as by reversing the direction of the power tailgate operation or by stopping the operation of the door or tailgate. 
     On the other hand, other types of movement, such as the oscillation  510  associated with the individual  502  getting out of the vehicle, may be indicative (e.g., when the first and second measurements are analyzed by the ECU  110 ) of movement of both the first accelerometer  112  and the second accelerometer  122  in a concurrent fashion, thereby enabling the ECU  110  to infer that no anti-entrapment measures are to be implemented, for example. 
     Because the first accelerometer  112  and the second accelerometer  122  are mounted at different positions, the difference in movement detected by the respective accelerometers may be measured, and movement of the vehicle as a whole may be determined, enabling movement associated with the power tailgate  120  to be isolated from the movement near the ECU accelerometer  112 , thereby enabling the ECU  110  to implement entrapment mitigation operations of the power tailgate  120  (e.g., by controlling the motor controller  130 ) more efficiently and/or accurately (e.g., mitigating false positives and more accurately determining entrapment scenarios). 
       FIG. 6  is an illustration of an example component diagram of the system  100  for vehicle power door operation, according to one aspect. The system  100  for vehicle power door operation may include the vehicle having the vehicle body  102 , the ECU  110 , an accelerometer (e.g., the first accelerometer  112  of  FIG. 1 ) integral to the ECU  110 , a processor  622 , and a memory  624 . The processor  622  and memory  624  may perform the determinations or calculations described herein using the measurements received from respective accelerometers. The memory  624  may store control maps or control tables which may include instructions for the motor controller  130  for power operations of the power door or power tailgate  120 . The ECU  110  may modify or adjust the implementation of these control maps or control tables based on the aforementioned features related to the first measurement taken by the first accelerometer  112  and the second measurement taken by the second accelerometer  122 . 
     Additionally, other accelerometers (e.g., the third accelerometer  212  of  FIG. 2 ) may be mounted to other portions of the vehicle body  102 . The system  100  may include a vehicle door structure which may be the power tailgate  120 , and include the second accelerometer  122 . A motor system  612  may include the motor controller  130  driving a motor  614 , which enables power operations of the power tailgate  120  or vehicle door structure by moving the power door or power tailgate  120 . The system  100  may include a bus  602  which operably connects the first accelerometer  112 , the second accelerometer  122 , the motor controller  130 , and the ECU  110 . 
       FIG. 7  is an illustration of an example flow diagram of a method  700  for vehicle power door operation, according to one aspect. The method  700  may include receiving a first measurement from a first accelerometer  112  mounted to a first portion of a vehicle at  702 , receiving a second measurement from a second accelerometer  122  mounted to a second portion of the vehicle at  704 , determining an orientation of the vehicle relative to a reference plane  160  based on the first and second measurements at  706 , determining a movement of the vehicle relative to the reference plane  160  based on the first and second measurements at  708 , and adjusting a power operation of a power door, power trunk, or power tailgate  120  via a motor controller  130  based on the determined orientation and/or the determined movement at  710 . 
     According to one aspect, the determined orientation may include an orientation of the vehicle (e.g., facing uphill or facing downhill), an angle  370  of the incline  310  (e.g., hill), an angle  270  of a door relative to a reference plane  160  or another reference plane  250  (e.g., gravity), a weight associated with the power door or power tailgate  120 , etc. Further, the determined movement may include a vibration of the vehicle localized near the power door or power tailgate  120 , an oscillation of the vehicle as a whole, etc. In any event, the power operation may be adjusted accordingly and in a manner to improve safety and/or implement anti-entrapment (e.g., by commanding the motor controller  130  to reverse a direction of operation, slow down, speed up, increase torque in a first direction, increase torque in a second direction, decrease torque, cease or stop operation, etc.). 
     Thus, as seen from the above description, the systems and techniques described herein provide for many benefits and are advantageous in several different ways. For example, the systems and methods for vehicle power door operation may account for more than merely the position and the speed of the power door relative to the position and the speed of the vehicle body  102  by accounting for the impact associated with gravity  250  and the orientation of the vehicle with respect to the incline  310  (e.g., determining whether the vehicle is parked on an up-slope or on a down-slope). 
     Additionally, if power is lost and subsequently restored, the use of the accelerometers enables the system  100  to continue operation without any need for calibration because accelerometers do not need to be reset to a home position to be utilized. In this way, the two or more accelerometers mounted at different locations of the vehicle enable the system  100 , in real-time, to compensate for movement and/or orientation of the vehicle and/or an incline  310  during operation of the power door or the power tailgate  120 . 
     Still yet another benefit of the systems and methods for vehicle power door operation is the determination of movement of different portions of the vehicle relative to one another and to the environment or the reference plane  160 . For example, with reference to  FIG. 5  described above, it can be seen that the vehicle body  102  of the vehicle and the power tailgate  120  of the vehicle move generally in unison. However, in other scenarios, such as where a child is jumping in the backseat of the vehicle, the vehicle body  102  of the vehicle and the power tailgate  120  of the vehicle may not necessarily move in concert with one another. As yet another example, if a passenger sits in the front passenger seat while the power tailgate  120  is closing, the system  100  may receive inputs from both the first accelerometer  112  and the second accelerometer  122 , and the ECU  110  may control the motor controller  130  of the power tailgate  120  accordingly. 
     Still another aspect involves a computer-readable medium including processor-executable instructions configured to implement one aspect of the techniques presented herein. An embodiment of a computer-readable medium or a computer-readable device devised in these ways is illustrated in  FIG. 8 , wherein an implementation  800  includes a computer-readable medium  808 , such as a CD-R, DVD-R, flash drive, a platter of a hard disk drive, etc., on which is encoded computer-readable data  806 . This encoded computer-readable data  806 , such as binary data including a plurality of zero&#39;s and one&#39;s as shown in  806 , in turn includes a set of processor-executable computer instructions  804  configured to operate according to one or more of the principles set forth herein. In one such embodiment  800 , the processor-executable computer instructions  804  may be configured to perform a method  802 , such as the method  700  of  FIG. 7 . In another aspect, the processor-executable computer instructions  804  may be configured to implement a system, such as the system  100  of  FIG. 6 . Many such computer-readable media may be devised by those of ordinary skill in the art that are configured to operate in accordance with the techniques presented herein. 
     As used in this application, the terms “component”, “module,” “system”, “interface”, and the like are generally intended to refer to a computer-related entity, either hardware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, or a computer. By way of illustration, both an application running on a controller and the controller may be a component. One or more components residing within a process or thread of execution and a component may be localized on one computer or distributed between two or more computers. 
     Further, the claimed subject matter is implemented as a method, apparatus, or article of manufacture using standard programming or engineering techniques to produce software, firmware, hardware, or any combination thereof to control a computer to implement the disclosed subject matter. The term “article of manufacture” as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. Of course, many modifications may be made to this configuration without departing from the scope or spirit of the claimed subject matter. 
       FIG. 9  and the following discussion provide a description of a suitable computing environment to implement aspects of one or more of the provisions set forth herein. The operating environment of  FIG. 9  is merely one example of a suitable operating environment and is not intended to suggest any limitation as to the scope of use or functionality of the operating environment. Example computing devices include, but are not limited to, personal computers, server computers, hand-held or laptop devices, mobile devices, such as mobile phones, Personal Digital Assistants (PDAs), media players, and the like, multiprocessor systems, consumer electronics, mini computers, mainframe computers, distributed computing environments that include any of the above systems or devices, etc. 
     Generally, embodiments or aspects are described in the general context of “computer readable instructions” being executed by one or more computing devices. Computer readable instructions may be distributed via computer readable media as will be discussed below. Computer readable instructions may be implemented as program modules, such as functions, objects, Application Programming Interfaces (APIs), data structures, and the like, that perform one or more tasks or implement one or more abstract data types. Typically, the functionality of the computer readable instructions are combined or distributed as desired in various environments. 
       FIG. 9  illustrates a system  900  including a computing device  912  configured to implement one aspect provided herein. In one configuration, computing device  912  includes at least one processing unit  916  and memory  918 . Depending on the exact configuration and type of computing device, memory  918  may be volatile, such as RAM, non-volatile, such as ROM, flash memory, etc., or a combination of the two. This configuration is illustrated in  FIG. 9  by dashed line  914 . 
     In other aspects, computing device  912  includes additional features or functionality. For example, computing device  912  may include additional storage such as removable storage or non-removable storage, including, but not limited to, magnetic storage, optical storage, etc. Such additional storage is illustrated in  FIG. 9  by storage  920 . In one aspect, computer readable instructions to implement one aspect provided herein are in storage  920 . Storage  920  may store other computer readable instructions to implement an operating system, an application program, etc. Computer readable instructions may be loaded in memory  918  for execution by processing unit  916 , for example. 
     The term “computer readable media” as used herein includes computer storage media. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions or other data. Memory  918  and storage  920  are examples of computer storage media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Disks (DVDs) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which may be used to store the desired information and which may be accessed by computing device  912 . Any such computer storage media is part of computing device  912 . 
     The term “computer readable media” includes communication media. Communication media typically embodies computer readable instructions or other data in a “modulated data signal” such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” includes a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. 
     Computing device  912  includes input device(s)  924  such as keyboard, mouse, pen, voice input device, touch input device, infrared cameras, video input devices, or any other input device. Output device(s)  922  such as one or more displays, speakers, printers, or any other output device may be included with the computing device  912 . Input device(s)  924  and output device(s)  922  may be connected to the computing device  912  via a wired connection, wireless connection, or any combination thereof. In one aspect, an input device or an output device from another computing device may be used as input device(s)  924  or output device(s)  922  for computing device  912 . The computing device  912  may include communication connection(s)  926  to facilitate communications with one or more other devices  930 , such as through network  928 , for example. 
     Although the subject matter has been described in language specific to structural features or methodological acts, it is to be understood that the subject matter of the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example embodiments. 
     Various operations of embodiments are provided herein. The order in which one or more or all of the operations are described should not be construed as to imply that these operations are necessarily order dependent. Alternative ordering will be appreciated based on this description. Further, not all operations may necessarily be present in each embodiment provided herein. 
     As used in this application, “or” is intended to mean an inclusive “or” rather than an exclusive “or”. Further, an inclusive “or” may include any combination thereof (e.g., A, B, or any combination thereof). In addition, “a” and “an” as used in this application are generally construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form. Additionally, at least one of A and B and/or the like generally means A or B or both A and B. Further, to the extent that “includes”, “having”, “has”, “with”, or variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term “comprising”. 
     Further, unless specified otherwise, “first”, “second”, or the like are not intended to imply a temporal aspect, a spatial aspect, an ordering, etc. Rather, such terms are merely used as identifiers, names, etc. for features, elements, items, etc. For example, a first channel and a second channel generally correspond to channel A and channel B or two different or two identical channels or the same channel. Additionally, “comprising”, “comprises”, “including”, “includes”, or the like generally means comprising or including, but not limited to. 
     It will be appreciated that various of the above-disclosed and other features and functions, or alternatives or varieties thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.