Commonly Used Terms

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comma.ai Terms

TermAbbreviationDefinition
comma.aiThe company behind openpilot
comma APIlink to docs
comma connectAn open source progressive web app used to view drives and interact with the device remotely
car harnessA universal interface to your car. A unique harness exists for each of the supported makes and models of cars. This replaces the older giraffe Connector
comma pedalA device that provides stop-and-go capability on cars that don't currently support it. This device is not sold by comma.ai (not officially supported by them), but supported in openpilot.
comma pointsAwarded for various activities you perform on the platform. Good for bragging rights.
comma powerCPv1, CPv2Use your car's OBD-II port to power your Toyota, Bosch, or FCA giraffe. CPv1 was the initial version, for use w/ giraffes. CPv2 came out later, used with comma harness, and has an RJ45 jack.
comma primeA subscription service from comma.ai offering a specific list of benefits
comma three devkitC3, comma threeThe latest generation devkit from comma. Runs Ubuntu linux and suppors the latest openpilot releases. Has an integrated panda (dos). Supports using an external red panda to interface with CAN-FD vehicles.
comma two devkitC2, comma twoA smartphone running a customized version of Android and a custom case with additional cooling. This device runs the openpilot software and has an integrated panda (uno)
EON devkitEON, EON Gold, EON SEThe previous generation of the comma two devkit. It did not have an integrated panda
fingerprintFPv1, FPv2A list of CAN bus signals unique to a particular vehicle. Allows openpilot to recognize which car it is connected to. CAN-based FPv1 is now deprecated; emphasis is now on firmware-based FPv2.
FrEON"Free EON"... an open source variant of the EON case. The repository contains files that can be used for 3D printing a case. Developed by @Chase#7213
giraffe connectorAn adapter board that lets you read buses that aren't exposed on the main OBD-II connector, with variants for different vehicle makes/models.
Lane Change AssistLCAActivate the turn signal and gently nudge the wheel in the direction you wish to travel to when it's safe. Change lanes while always paying attention.
LeEco Le Pro 3LeEco, LeproThe phone used in comma two and EON Gold devkits
LiveParametersA continually updated file (ie. "Live") that stores learned calibration data for the vehicle.
OnePlus 3Top3tOne of the phones used in the previous generation EON devkits. It was discontinued due to a lack of supply. Known model numbers: A3000(US version) A3010(Asian version)
openpilotopAn open source driver assistance system developed by comma.ai
pandaCAN bus interface. Available in 3 variants: white (last supported 0.7.6.1) / grey (last supported 0.7.10) / black. Internal pandas are also found inside the
comma two (uno) and comma three (dos).
panda pawA device to help you unbrick a panda.



openpilot Terms

TermAbbreviationDefinition
big modelA new paradigm in model development that takes a bigger input frame. Full frame is 1164x874, little model is a 512x256 crop, big model is a 1024x512 crop, 4x bigger than little. Make box bigger, drive better. Useful for signs and lights.
Driving ModelmodelThe resulting neural network after Comma trains on driving data on their supercomputer. This file lives on the device, and processes inputs to give outputs relevant to driving. Usually takes the form of an ONNX file, or a THNEED file after compilation on device. This file does not change or get trained on device, only processes inputs and outputs. See the list of driving models for names and details of models over time.
End to ende2eEnd to end means the model reacts like a human would. It assesses the whole picture and acts accordingly. Unlike other approaches where things must be labeled by hand, end to end learns all the nuances of driving. A model is basically trained on what human drivers would do in a certain situation and attempts to reproduce that behavior.
longitudinallongRefers to gas and brake control
laterallatRefers to steering control
Model predictive controlmpcAn advanced method of process control that is used to control a process while satisfying a set of constraints. Used for longitudinal and lateral control.
leadSelected radar point from your car's radar by the driving model of openpilot using the camera. Used for longitudinal MPC. Usual attributes: distance, speed, and acceleration



Driver-Assistance Terms

Make-specific terms should be added to their perspective wiki page.

TermAbbreviationDefinition
Adaptive Cruise ControlACCA cruise control system that automatically adjusts the vehicle speed to maintain a safe distance from vehicles ahead.
Advanced Driver-Assistance SystemsADASElectronic systems that aid the driver.
(Automatic) Lane Centering(A)LCA system designed to keep a car centered in the lane, relieving the driver of the task of steering.
Collision Avoidance SystemAEB, CMS, FCW(S), FCA, PCSA system designed to prevent or reduce the severity of a collision.
Driver Monitoring (System)DM(S), DAMA system that uses infrared sensors and/or cameras to monitor driver attentiveness
Dynamic Range Cruise ControlDRCCA cruise control system that automatically adjusts the vehicle speed to maintain a safe distance from vehicles ahead.
huggingAn undesired behavior where the vehicle drives too closely to one side of the lane.
Lane Keep Assist (System)LKA(S)Lane keep assist is what comes with most cars sold today. It will assist the driver if they go over a lane line, but will not keep the car centered in the lane.
Lane Departure Warning (System)LDW(S), LDALane departure warning will beep when a car goes over a lane line.
Pedestrian Crash Avoidance MitigationPCAMA system that uses computer and artificial intelligence technology to recognize pedestrians and bicycles in an automobile's path to take action for safety.
ping pongAn undesired behavior where the vehicle sways from one side of the lane to the other repeatedly. The desired behavior is to stay in the center of the lane.
wobbleSimilar to ping pong, but where the vehicle drives mostly centered in the lane but sways slightly from side to side. Primarily due to improper tuning of the steering control system, influence from wind, or poor lane/path perception due to rain, dirt, and/or debris on the vehicles windshield.
Traffic-sign recognitionTSRA system by which a vehicle is able to recognize the traffic signs put on the road e.g. "speed limit" or "children" or "turn ahead".
Stop and GoSnGThe ability for the car to be brought to a standstill and then resume driving without needing to disengage or reengage openpilot.
Vision Only Adaptive Cruise ControlVOACCThe exclusive use of cameras instead of radar to provide adaptive cruise control functions.



Automotive Terms

Make-specific terms should be added to their perspective wiki page.

TermAbbreviationDefinition
Controller Area NetworkCAN, CAN busA message-based protocol that provides a standardized way for ECUs to communicate with each other.
CAN-FDA newer version of CAN that supports higher data rates and longer messages. A red panda is required to interface with CAN-FD vehicles.
Electronic Control UnitECUAny embedded system in automotive electronics that controls one or more of the electrical systems or subsystems in a vehicle.
Electric Power SteeringEPSUses an electric motor to assist the driver of a vehicle. Sensors detect the position and torque of the steering column, and a computer module applies assistive torque via the motor, which connects to either the steering gear or steering column.
On-Board Diagnostics ConnectorOBD-II, OBD-II portOBD systems give the vehicle owner or repair technician access to the status of the various vehicle sub-systems. The comma power v2 uses this port to provide constant power to the comma two as well as access the diagnostic bus for FW query.
Full Self DrivingFSD



Discord Terms

TermAbbreviationDefinition
Direct MessageDM (PM preferred to avoid confusion with driver monitoring)Private message to an individual on Discord
Private MessagePMPrivate message to an individual on Discord
Want To BuyWTBYou want to buy an item (on #for-sale channel)
For SaleFSYou want to sell an item (on #for-sale channel)