Adaptive Cruise Control

Quick Overview: 

• Utilizes an Intelligent Adaptive Cruise Control (iACC/DASM) module, the Traffic Sign Recognition system used in conjunction with the Forward Facing Camera (FFC/HALF) to identify vehicles in traffic, speed limit signs, vehicles forward path and maintains a selectable distance between the host vehicle and the vehicle in front of it.
• Speed limits are suggested to the driver. This come from the Traffic Sign Recognition system in which the Forward Facing Camera (FFC/HALF) recognizes road speed limit signs. Once the driver receives the speed suggestion, the driver can chose to set the sign speed limit as the speed target or reject the suggestion through the rocker switch.
• ACC with stop and go has full functionality between 0 and 100 mph.
• After ACC with stop and go brings the vehicle to a stop, the driver must indicate the intention to resume by either pressing the resume button or tapping the accelerator pedal.
• Driver can select one of four following distances depending on driver preference.

Preconditions for ACC operation:

• The system must be turned ON  .
• The engine must be running.
• The host vehicle is either moving forward or is in a standstill.
  • ACC with Stop and Go operates at 0 kph/mph
  • ACC with Follow to Stop: the minimum speed is 5 kph or higher
  • ACC base system speeds need to be 30 kph or higher
• The ESC must be present and not in a fault condition.
• The EPB must be preset for the ACC Stop and Go feature.
• Subject vehicle speed must be within operating parameters.
• Operational road types: urban and inter-urban roads; straight and curved roads with a road curvature radius equal to or less than 125 m; roads with positive or negative inclination transition (changes in road grade) up to 2%.
• Operational environment conditions: all weather conditions even if heavy rain and snow could reduce the performances of the system due to the conditions of the road surface. In any case the FFC/HALF and the ACC/DASM is operative unless there is a blockage to either components.
• Operational low-light conditions: the system performances and detection range are not affected by low light environments if the target vehicle(s) have their lights turned on.

Functional Overview -  The iACC system has functionality beyond that of Normal Cruise Control and Adaptive Cruise Control. This system has the functionality of the cruise control system of maintaining a driver defined Set Speed without the driver needing to press the throttle. This system also has the functionality of the regular ACC system of increasing and decreasing the vehicle speed based on target vehicles moving slower than the ACC Set Speed. Beyond the functionality of the regular ACC system, this system offers a larger operational speed range, which constitutes of speeds from 0 mph to a configurable upper bound. If a target vehicle comes to a standstill, the ACC system will also bring the ACC host vehicle to a stop, and will keep the vehicle at a standstill for an undetermined period of time by first applying the brakes, and after the brakes time-out, cancelling the ACC system and applying the Electronic Park Brake (EPB). The ACC with stop and go system will also incorporate Forward Collision Warning-Plus (FCW). With grade braking, the transmission will automatically downshift to maintain selected vehicle speed and distance, preventing overheating of brakes.

iACC uses the FFC/HALF in conjunction with the Traffic Sign Recognition system to detect road speed limit signs in either metric or imperial and supplies a customer with a suggested speed control setting. The customer has the option to concur or ignore the suggested settings by use of the rocker switch.

The ACC/DASM, FFC/HALF, ABS module, IPC, EVIC, PCM, SCCM and the BCM each contain a microcontroller and programming that allow them to communicate with each other using the Controller Area Network (CAN) data bus. This method of communication is used by the ACC module to provide inputs to the ABS module, the EVIC and the PCM. This is also is used by the ABS module to provide inputs to the PCM, by the SCCM to relay the status of the speed control switches to the PCM and by the PCM for control of the indicators in the IPC and the indications in the EVIC. Refer to COMMUNICATION, DESCRIPTION .

The BCM is responsible for gateway data management for the entire systems in use for ACC and its variants.

The ACC with stop and go system used also incorporates grade braking and FCW. With grade braking, the transmission will automatically downshift to maintain selected vehicle speed and distance, preventing overheating of brakes.