Autonomous vehicle interface using bus impedance to identify control units, and associated systems and methods
Systems and methods that facilitate identifying and controlling the systems and subsystems in a vehicle to enable autonomous operation of the vehicle are disclosed. An autonomous vehicle interface (AVI) (the “AVI control system”) can interface with and control the system of the vehicle, thereby enabling control of the vehicle as a whole. Electronic control units may be associated with each of the systems and subsystems in the vehicle, and the AVI may interface with and control these electronic control units over a shared data bus. In order to control particular electronic control units, the systems and methods provide for sampling data packets transmitted by the electronic control units on the shared data bus, measuring the impedance of the shared data bus when data packets are being transmitted, and identifying particular electronic control units based on the measured impedance.
1. A method, performed by an autonomous vehicle interface, to identify electronic control units in a vehicle, the method comprising:
sampling data from a data frame transmitted over a shared data bus in the vehicle, wherein multiple electronic control units are coupled to the shared bus;
determining whether the sampled data of the data fame is from a data field in the data frame; and,
measuring the impedance of the shared bus when it is determined that the sampled data is from the data field of the data frame.
2. The method of claim 1 , further comprising storing the measured impedance in a system memory.
3. The method of claim 1 , wherein determining whether the sampled data of the data fame is from a data field in the data frame comprises determining whether the sampled data is from a data payload transmitted by an electronic control unit.
4. The method of claim 3 , further comprising, when it is determined that the sampled data is not from a data payload transmitted by an electronic control unit, sampling the next data frame transmitted over the shared bus.
5. The method of claim 2 , further comprising receiving a plurality of data payloads from the multiple electronic control units, and associating the data payloads with the stored, measured impedances.
6. A system for identifying electronic control units in a vehicle, the system comprising:
a plurality of electronic control units,
a shared communication bus, wherein the plurality of electronic control units are configured to transmit data frame over the shared communication bus, and
an autonomous vehicle interface configured coupled to the shared communication bus, wherein the autonomous vehicle interface is configured to:
sample data from a data frame transmitted over the shared communication bus in the vehicle,
determine whether the sampled data of the data fame is from a data field in the data frame; and,
measure the impedance of the shared bus when it is determined that the sampled data is from the data field of the data frame.
7. The system of claim 6 , wherein the autonomous vehicle interface comprises an analog-to-digital converter and a memory.