Vehicle sensor calibration using wireless network-connected sensors

Method and apparatus are disclosed for vehicle sensor calibration using wireless network-connected sensors. An example disclosed vehicle includes a communication controller and a sensor manager. The example communication controller communicatively couples to a network associated with a facility. The example sensor manager determines when the vehicle is proximate the facility. Additionally, the sensor manager calibrates sensors of the vehicle based on a measurement data of sensors installed at the facility that are communicatively coupled to the network.

TECHNICAL FIELD

The present disclosure generally relates to vehicle sensors and, more specifically, vehicle sensor calibration using wireless network-connected sensors.

BACKGROUND

Vehicles include sensors to measure conditions around the vehicle. Electronic control units of the vehicle use the measurements to control the subsystems of the vehicle. For example, humidity measurements from a vehicle humidity sensor may be used to correct distance measurements made by ultrasonic sensors. Overtime, in the relatively harsh environment in which the vehicle sensors operate, the accuracy of the sensors degrades. This degradation affects the control of the vehicle.

SUMMARY

Example embodiments are disclosed for vehicle sensor calibration using wireless network-connected sensors. An example disclosed vehicle includes a communication controller and a sensor manager. The example communication controller communicatively couples to a network associated with a facility. The example sensor manager determines when the vehicle is proximate the facility. Additionally, the sensor manager calibrates sensors of the vehicle based on a measurement data of sensors installed at the facility that are communicatively coupled to the network.

An example method to calibrate first sensors of a vehicle includes, in response to the vehicle being proximate to facility with which it has a relationship, connecting to a wireless local area network of the facility. The example method also includes requesting measurement data from second sensors installed at the facility. The second sensors are communicatively coupled to the wireless local area network of the facility. Additionally, the method includes, based on the measurement data, calibrating the first sensors.

A tangible computer readable medium comprising instructions that, when executed cause a vehicle to, in response to the vehicle being proximate to facility with which it has a relationship, connect to a wireless local area network of the facility. The instructs also cause the vehicle to request measurement data from second sensors installed at the facility, the second sensors being communicatively coupled to the wireless local area network of the facility. Additionally, the instruction causes the vehicle to, based on the measurement data, recalibrate the first sensors.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Increasingly consumer devices include sensors that are connected to a network to provide remotely accessible information and remote control of the devices. Often, these facility-based sensors provide more accurate information than the sensors on vehicle because, for example, (a) they are typically less exposed to noise factors that are found on vehicles, (b) they often cost more and are more accurate, and/or (c) they may be less prone to degradation because they are not exposed to the harsh conditions the vehicle endures. As used herein, the term “facility-based sensors” refers to sensors (a) install in or around a permanent facility (e.g., a house, a gas station, etc.) and/or (b) installed on devices located in or around the facility. These facility-based sensors are connected to a network (e.g., a location area network, the Internet, etc.) and provide measurements over the network.

As disclosed below, a vehicle detects when it is in the vicinity of a facility in which the vehicle has a relationship. As used herein, the vehicle has a relationship with the facility when (a) the vehicle has been bonded (e.g., for a personal area network) and/or credentialed (e.g., for a wireless local area network) to access the network at the facility, and (b) the vehicle has access to sensor measurements from the facility-based sensors via the network. The vehicle determines when it is in the vicinity with such as facility using a global positioning system (GPS) receiver and/or being within range to connect to the network. In some examples, the vehicle detects that it is in the vicinity of a facility at which it has a relationship and then awakes a communication controller to establish a connection with the facility.

Once a connection is established, the vehicle receives a list of sensors at the facility and associated estimated accuracy of the sensors. The vehicle compares the estimated accuracy of the sensors available at the facility with the calibrations of the sensors of the vehicle. For the facility sensors that (a) have a greater estimated accuracy than the vehicle sensors (b) have a greater estimated accuracy than previous calibrations (e.g., from other facilities, etc.), the vehicle performs a calibration strategy on the vehicle sensor. In some examples, the calibration strategy used for different vehicle sensors is different based on which sensor is being calibrated. For example, the calibration strategies may include an offset or gain application, simple value substitution, transfer function shift, and/or a sweep calibration, etc. Additionally, the vehicle stores the estimated accuracy of the facility sensor.

FIG. 1illustrates a vehicle100located in the vicinity of a facility102with network-connected sensors104aand104bin accordance with the teachings of this disclosure. The example facility102is any suitable location with network-connected sensors104aand104bthat are connected to a network, such as a house, a gas station, an auto dealership, and/or a parking garage, etc. In the illustrated example, the facility102includes the network-connected sensors104aand104b, and a network communication controller106. In some examples, the facility102also includes a network bridge108.

The network-connected sensors104aand104bmeasure the environment around the facility102. The network-connected sensors104aand104binclude humidity sensors, temperature sensors, pressure sensors, air quality sensors, ambient light sensors, and/or rain sensors, etc. In some examples, the network-connected sensors104aare stand alone sensors (e.g., sensors that are not incorporated into another device) and/or sensors that are incorporated into another device, such as an appliance. For example, the network-connected sensors104amay be incorporated into a weather station. In some examples, the network-connected sensors104bare incorporated into a sensor package designed to have the sensors (e.g., the sensors110below) of the vehicle100. For example, a sensor package104bmay be manufactured for a specific vehicle100and included when the vehicle100is purchased. In the illustrated example, the sensor package104bis affixed to a wall of the facility (e.g., a wall of a garage in which the vehicle100parks). When requested, the network-connected sensors104aand104b(or, in some examples, a controller of the sensor package104b) provide measurement data. The measurement data includes (i) a sensor reading, and (ii) an estimated accuracy of the corresponding network-connected sensors104aand104b. For examples, a barometer of a network-connected weather station may have an accuracy of ±0.08 inHg (inches of mercury). The network-connected sensors104aand104bshare the measurement data on a network107via a connected to the network communication controller106.

The network communication controller106facilitates the connection of the network-connected sensors104aand104bto a network. The network communication controller106includes hardware (e.g., processors, memory, storage, antenna, etc.) and software to control wireless network interfaces. In some examples, the network communication controller106is a wireless local area network (WLAN) controller that establishes a wireless location area network (e.g., the network107) implementing a WLAN protocol (e.g., IEEE 802.11 a/b/g/n/ac, etc.). In some examples, the network-connected sensors104aand104bupload senor readings to one or more external servers (not shown) via the network communication controller106. The network107may utilize a variety of networking protocols now available or later developed including, but not limited to, TCP/IP-based networking protocols.

The network bridge108is communicatively coupled to the network communication controller106. The network bridge108provides a communication interface to the vehicle100when, for example, the vehicle100does not include a network controller to connect to the WLAN network107of the network communication controller106. The example network bridge108includes hardware (e.g., processors, memory, storage, antenna, etc.) and software to control wireless network interfaces, such as Bluetooth® and Bluetooth® Low Energy (BLE) (as specified by the Bluetooth Specification and subsequent revisions maintained by the Bluetooth Special Interest Group), Z-Wave® (as specified by the Z-Wave Specification maintained by the Z-Wave Alliance), and/or Zigbee® (IEEE 802.15.4). In examples in which the network bridge108is used, the vehicle100communicatively couples to the network bridge108. The vehicle100then receives measurement data from the network-connected sensors104aand104bconnected to the network107via the network bridge108.

The vehicle100may 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 vehicle100includes parts related to mobility, such as a powertrain with an engine, a transmission, a suspension, a driveshaft, and/or wheels, etc. The vehicle100may be non-autonomous, semi-autonomous (e.g., some routine motive functions controlled by the vehicle100), or autonomous (e.g., motive functions are controlled by the vehicle100without direct driver input). In the illustrated example, the vehicle100includes sensors110, electronic control units (ECUs)112, an on-board communications platform114, a global positioning system (GSP) receiver116, and a sensor manager118.

The sensors110may be arranged in and around the vehicle100in any suitable fashion. The sensors110may be mounted to measure properties around the exterior of the vehicle100. Additionally, some sensors110may be mounted inside the cabin of the vehicle100or in the body of the vehicle100(such as, the engine compartment, the wheel wells, etc.) to measure properties in the interior of the vehicle100. For example, such sensors110may include accelerometers, odometers, tachometers, pitch and yaw sensors, wheel speed sensors, microphones, tire pressure sensors, and biometric sensors, etc. In the illustrated example, the sensors110are electrically coupled to the ECUs112to provide sensor readings to the ECUs112. Overtime, the calibration of the sensors110may degrade as the sensors110are exposed to harsh environments (e.g., weather, internal heat of the engine compartment, etc.).

The ECUs112monitor and control the subsystems of the vehicle100. The ECUs112communicate and exchange information via a vehicle data bus (e.g., the vehicle data bus204ofFIG. 2below). Additionally, the ECUs112may communicate properties (such as, status of the ECU112, sensor readings, control state, error and diagnostic codes, etc.) to and/or receive requests from other ECUs112. Some vehicles100may have seventy or more ECUs112located in various locations around the vehicle100communicatively coupled by the vehicle data bus204. The ECUs112are discrete sets of electronics that include their own circuit(s) (such as integrated circuits, microprocessors, memory, storage, etc.) and firmware, sensors, actuators, and/or mounting hardware. The ECUs112use the sensor readings from the sensors110of the vehicle100to control the subsystems of the vehicle100. For example, the advanced driving assistance system (ADAS) may use the sensor readings to adjust distance calculations based on the sensor readings from a humidity sensor and a temperature sensor, and/or a powertrain control unit may control the traction control system based on sensor reading from a rain sensor. Additionally, the ECUs112maintain a calibration profile to the sensors110that adjusts readings from the sensors110. Originally, the calibration profile may be performed during a manufacturer process. As disclosed below, the calibration profile is updated from time to time by the sensor manager118. Example ECUs112include the ADAS, the powertrain control unit, a autonomy unit (e.g., an ECU112that controls the motive functions of the vehicle100when the vehicle100is autonomous), a telematics unit.

The on-board communications platform114includes wired or wireless network interfaces to enable communication with external networks. The on-board communications platform114also includes hardware (e.g., processors, memory, storage, antenna, etc.) and software to control the wired or wireless network interfaces. The on-board communications platform114includes one or more wireless controller(s) for wide area networks (e.g., Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), Code Division Multiple Access (CDMA), WiMAX (IEEE 802.16m), etc.), wireless local area wireless networks (e.g, IEEE 802.11 a/b/g/n/ac or others, dedicated short range communication (DSRC), etc.) and/or personal area networks (e.g., Bluetooth®, Bluetooth® Low Energy, Z-Wave®, Zigbee®, etc.). The on-board communications platform114connects to the network107provided by the network communication controller106or the network bridge108of the facility102to receive measurement data from the network-connected sensors104aand104bof the facility102. In some examples, the on-board communications platform114connects to a server on an external network (e.g., the Internet) via a cellular modem. In such examples, the network-connected sensors104aand104bof the facility102upload measurement data to the server to be retrieved via the on-board communications platform114.

The sensor manager118generates calibration profiles for the ECUs112based on measurement data from network-connected sensors104aand104bwhen the vehicle100is within a threshold distance (e.g., ten feet, twenty feet, thirty feet, etc.) (sometimes referred to as the “vicinity”). Even in examples where the sensor manager118is communicating with an external server on the Internet to receiving measurement data from the network-connected sensors104aand104b, the sensor manager118determines whether to recalibrate the sensors110when the vehicle100is in the vicinity of the facility so that the sensors110are measuring substantially the same phenomenon (e.g., the same pressure, the same ambient light, the same, temperature, etc.) as the network-connected sensors104aand104b. The sensor manager118determines when the vehicle100is in the vicinity of the facility102based on coordinates of the facility (e.g., stored in memory) and coordinates of the vehicle100provided by the GPS receiver116. In some examples, when the vehicle100does not includes the GPS receiver116, the sensor manager118determines the vehicle100is in the vicinity of the facility102when the vehicle100is within range of the network107provided by the network communication controller106and/or the network bridge108. In some examples, the sensor manager118determines the coordinates of the facility102when the sensor manager118develops a relationship with the facility102.

When the vehicle100is in the vicinity of the facility102, sensor manager118establishes a connection with the network107of the facility102. The sensor manager118requests a list of the network-connected sensors104aand104bconnected to the network107and corresponding measurement data (e.g., a sensor reading and estimated accuracy). In some examples, the sensor manager118requests the list and the corresponding measurement data from the facility102whenever the vehicle100is in the vicinity because (a) the facility102may add network-connected sensors104aand104bfrom time-to-time, and (b) the sensors110of the vehicle100may continue to degrade.

The sensor manager118monitors the sensors110of the vehicle100(e.g., via the calibration profiles of the sensors110) to determine the estimated accuracy of the sensor110, the current sensor reading and/or the most recent date of calibration of the sensor110. Based on the calibration profiles of the sensors110and the measurement data from the network-connected sensors104aand104b, the sensor manager118determines whether to recalibrate one or more of the sensors110. For example, the estimated accuracy of the corresponding network-connected sensor104aand104bmay be greater than the estimated accuracy of network-connected sensor104aand104bused to previously calibrate the sensor110. As another example, a comparison of the sensor reading from the sensor110and the measurement data from the corresponding network-connected sensor104aand104bmay indicate that the accuracy of the sensor110has degraded more since the last calibration. For example, if the sensor110of the vehicle100is a humidity sensor with an accuracy of ±4.0 percent relative humidity and one of the network-connected sensors104aand104bis a humidity sensor with an accuracy of ±2.0 percent relative humidity, then the sensor manager118may generate a calibration profile for the sensor110.

If the sensor(s)110is/are to be recalibrated, the sensor manager118generates the calibration profile(s) for the sensor(s)110. The sensor manager118calibrates the sensors110using a calibration strategy. The calibration strategy is based on the particular sensor110is being calibrated. The calibration strategies include an offset or gain application, simple value substitution, transfer function shift, and/or a sweep calibration, etc. For example, if the sensor110of the vehicle100is a humidity sensor that measures 71 percent relative humidity and the one of the network-connected sensors104aand104bis a humidity sensor that measures 68 percent relative humidity, the sensor manager118may generates the calibration profile for the sensor indicating (a) the calibration strategy is an offset, (b) the estimated accuracy of the network-connected sensor104aand104bis ±2.0 percent relative humidity, and (c) the offset is 3% relative humidity. The sensor manager118communicates the calibration profiles to the relevant ECUs112(e.g., the ECUs112that use the sensor readings from the particular sensor110).

When the vehicle100is initially in the vicinity of the facility102, the sensor manager118develops a relationship with the network107of the facility102via the on-board communications platform114. When prompted by a user (e.g., via a center console display (not shown)), the sensor manager118detects the network107(e.g., by detecting the network107or detecting the network bridge108). The on-board communications platform114bonds with the network communication controller106though, for example, providing credentials (e.g. password, etc.). After bonding, the sensor manager118subsequently connects to the network107when the network107is within range.

FIG. 2is a block diagram of electronic components200of the vehicle100ofFIG. 1. The electronic components200include the sensors110, the ECUs112, the on-board communications platform114, the GPS receiver116, an on-board computing platform202, and a vehicle data bus204.

The on-board computing platform202includes a processor or controller206and memory208. In some examples, the on-board computing platform202is structured to include the sensor manager118. Alternatively, in some examples, the sensor manager118is incorporated into another ECU112(e.g., the ADAS, the telematics unit, etc.) with its own processor and memory. The processor or controller206may 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 memory208may 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, memristor-based 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 memory208includes multiple kinds of memory, particularly volatile memory and non-volatile memory.

The memory208is 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 memory208, the computer readable medium, and/or within the processor206during execution of the instructions.

The vehicle data bus204communicatively couples the ECUs112, the on-board communications platform114, the GPS receiver116, and/or the on-board computing platform202, etc. In some examples, the vehicle data bus204includes one or more data buses. The vehicle data bus204may be implemented in accordance with a controller area network (CAN) bus protocol as defined by International Standards Organization (ISO) 11898-1, a Media Oriented Systems Transport (MOST) bus protocol, a CAN flexible data (CAN-FD) bus protocol (ISO 11898-7) and/or a K-line bus protocol (ISO 9141 and ISO 14230-1), and/or an Ethernet™ bus protocol IEEE 802.3 (2002 onwards), etc.

FIG. 3is a flowchart of a method to calibrate the sensors110of the vehicle100ofFIG. 1using the network-connected sensors104aand104bof the facility102, which may be implemented by the electronic components200ofFIG. 2. Initially, at block302, the sensor manager118waits until the vehicle100is in the proximity of the facility102. The sensor manager118uses the coordinates from the GPS receiver116and/or monitors the availability of the network(s) associated with the facility102to determine when the vehicle100is proximate the facility102. At block304, the sensor manager118establishes communication with the facility102via the network107. In some examples, the sensor manager118connects with the network bridge108via a personal area network protocol.

At block306, the sensor manager118receives a list of the network-connected sensors104aand104bthat are connected to the network107. In some examples, the list also includes measurement data (e.g., sensor reading(s) and estimated accuracy) from the network-connected sensors104aand104b. At block308, the sensor manager118queries the sensors110of the vehicle100. The sensors110and/or the associated ECU(s)112provide the current estimated accuracy of the sensor110and a sensor reading from the sensor110.

At block310, the sensor manager118selects the next one of the sensors110to analyze. At block312, the sensor manager118compares the estimated accuracy of the corresponding network-connected sensor104aand104bto the estimates accuracy of the sensor110selected at block310. In some examples, the sensor manager118also compares the sensor readings of the corresponding network-connected sensor104aand the selected sensor110. In some such examples, the sensor manager118requests several sensor readings from the selected sensor110and the corresponding network-connected sensor104aand104band considers the average values of the sensor readings over a period of time. At block314, the sensor manager118determines whether to recalibrate the selected sensor110. The sensor manager118determines to recalibrate the selected sensors110when (a) the corresponding network-connected sensor104aand104bis more accurate than the sensor110and/or (b) sensor readings (or the average sensor readings) differ by a threshold value (e.g., the threshold being the estimated error of the network-connected sensor104aand104b). For example, if (i) the sensor110of the vehicle100is a humidity sensor with an accuracy of ±4.0 percent relative humidity, (ii) the corresponding network-connected sensor104aand104bhas an accuracy of ±2.0 percent relative humidity, and (iii) the average difference between the sensor readings is 2.6 percent relative humidity, the sensor manager118may recalibrate the selected sensor110. At block316, the sensor manager118performs a calibration strategy on the selected sensor110based on the accuracy and the sensor reading(s) of the corresponding network-connected sensor104aand104b. At block318, the sensor manager118determines whether there is another sensor110to analyze. If there is another sensor110, the method returns to block310. Otherwise, if there is not another sensor110, the method ends.

The flowchart ofFIG. 3is representative of machine readable instructions stored in memory (such as the memory208ofFIG. 2) that comprise one or more programs that, when executed by a processor (such as the processor206ofFIG. 2), cause the vehicle100to implement the example sensor manager118ofFIGS. 1 and 2. Further, although the example program(s) is/are described with reference to the flowchart illustrated inFIG. 3, many other methods of implementing the example sensor manager118may 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.