ASE L4 ADAS Specialist flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

ADAS Level 2

Partial automation where the system can simultaneously control steering and speed, but the driver must monitor and be ready to take over at all times.

Sensor fusion

Combining data from multiple sensors (camera, radar, lidar) to produce a more reliable perception of the environment than any single sensor alone.

ASIL

Automotive Safety Integrity Level from ISO 26262; ranges from A (lowest) to D (highest) and defines required safety measures for a function.

Domain controller

A central ECU that processes sensor data and coordinates multiple ADAS features, often bridging CAN, FlexRay, and Ethernet networks.

Radar Doppler effect

The frequency shift of a reflected radar signal proportional to the relative velocity between the sensor and the target, used to measure closing speed.

Lidar time of flight

A ranging method that measures the time for a laser pulse to travel to an object and return, then converts it to distance using the speed of light.

Camera intrinsic calibration

The process of determining a camera's internal parameters such as focal length and principal point, which correct for lens and sensor characteristics.

Radar bumper attenuation

Reduction in radar signal strength caused by bumper material, thickness, or metallic paint; excessive attenuation can degrade range and cause faults.

AEB

Autonomous Emergency Braking; a system that detects an imminent collision and automatically applies brakes to reduce severity or avoid impact.

ACC time gap

The driver-selectable following distance in Adaptive Cruise Control, expressed as the time to reach the lead vehicle at current speed.

LKA vs LDW

Lane Keeping Assist applies steering torque to keep the vehicle centered, while Lane Departure Warning only alerts the driver of an unintended lane crossing.

BSM

Blind Spot Monitoring; uses side/rear radar to detect vehicles in adjacent lanes and warn the driver, often with a mirror indicator.

TSR

Traffic Sign Recognition; a camera-based feature that detects speed limit and other signs and displays them to the driver, sometimes fused with navigation data.

Static calibration

Sensor calibration performed in a controlled bay using precisely positioned targets at OEM-specified distances and heights, with the vehicle stationary.

Dynamic calibration

Sensor calibration performed while driving under specified conditions (speed, lane markings, lighting) so the system can learn from road features.

Calibration prerequisites

Conditions that must be met before calibration, including correct tire pressure, ride height, fuel level, level surface, and no unresolved DTCs.

Extrinsic calibration

Determining a sensor's position and orientation relative to the vehicle coordinate frame, critical for accurate object localization.

Radar corner reflector

A target with three mutually perpendicular plates that reflects radar energy back to the source, used for radar aiming and calibration.

DTC format

A diagnostic trouble code with a system letter (P, C, B, U) followed by four digits; the first digit indicates generic (0) or manufacturer-specific (1).

Freeze frame

A snapshot of operating conditions (speed, load, temperature) stored when a DTC sets, used to reproduce and diagnose the fault.

Permanent DTC

A code that cannot be cleared with a scan tool; it clears only after the relevant monitor runs and passes under specified conditions.

U-code

A diagnostic trouble code for network communication faults; often indicates bus wiring, termination, or module power/ground issues.

CAN bus termination

Two 120-ohm resistors at opposite ends of the bus; measured resistance with power off should be about 60 ohms across CAN-H and CAN-L.

CAN FD

CAN with Flexible Data-rate; supports higher speeds and larger payloads than classic CAN, but all nodes on a segment must be compatible.

Automotive Ethernet

A single twisted-pair network (100BASE-T1 or 1000BASE-T1) used for high-bandwidth ADAS data; sensitive to cable damage and connector quality.

Voltage drop test

Measuring voltage lost across a circuit under load to find excessive resistance; preferred over ohmmeter testing for high-current sensor and actuator circuits.

Windshield camera recalibration

Required after windshield replacement or camera removal; ensures the camera's view through the new glass matches the vehicle's calibration.

Bumper paint and radar

Metallic or thick paint on a bumper covering radar can attenuate the signal; OEM paint specifications must be followed to avoid performance loss.

Ride height and calibration

Suspension repairs that change ride height alter sensor pitch and height; alignment and ride height checks must precede forward sensor calibration.

FMVSS 127

A U.S. federal motor vehicle safety standard requiring automatic emergency braking and related performance on new light vehicles.

Lidar eye safety

Lidar and infrared emitters can damage eyes; never look directly into the aperture and use appropriate eye protection during service.

Customer handoff documentation

Written record of calibrations, software versions, test drives, and feature limitations provided to the customer after ADAS repair.