In Focus: Collision avoidance systems

Several different types of crash avoidance technologies now exist, with amazing capabilities. Some effectively sharpen drivers’ senses, while others actually take control of various vehicle parameters to help drivers recover when a vehicle begins to go out of control. Systems like these could prove to be a new way to drop your overall costs.

Stability Enhancement

ArvinMeritor’s Roll Stability Control (RSC) is integrated into the ABS ECU. It consists of an accelerometer and a trailer brake modulation valve. Since it measures both vehicle speed and lateral acceleration, its sophisticated software can calculate the vehicle load and the speed at which the vehicle is likely to roll over. It controls engine and retarder torque through the J1939 data link, and also both tractor drive axle and trailer brakes. Drive axle brake control works through the Automatic Traction Control function. The power, retarder and braking functions are used in a sequence that can prevent most rollovers.

You can augment RSC with the Roll Stability Support (RSS) system for trailers. The software solution calculates wheel speed differences and can apply the trailer brakes independently to enhance roll stability further.

Tractor Electronic Stability Control has its own electronic module. It adds a steering angle sensor, a yaw rate sensor, a pressure sensor and a solenoid valve for front axle braking. It gives complete directional stability control for oversteering and understeering conditions to prevent jackknife and driftout.

Bendix Commercial Vehicle Systems
ABS-6 Advanced with ESP Stability System

Bendix Commercial Vehicle Systems offers its ABS-6, which consists of existing ABS and ATC (automatic traction control) components, plus sensors measuring lateral acceleration, steering angle, brake pressure, load and yaw rate.

When a driver speeds into a curve on high-friction pavement, the system applies air to all tractor and trailer brakes while reducing throttle. This reduces vehicle speed and mitigates the tendency for rollover.

When the driver rounds a curve at a speed that exceeds the tire adhesion, the result is tractor slide and trailer jackknife. The system senses the difference between the driver’s intended path and compares it to the vehicle path. The system applies brakes as needed.

The system’s performance is augmented by software Bendix calls ESP Performance Enhancement. The electronic control module (ECM) crosschecks the system’s sensors, shortening the reaction time and improving the accuracy of response. System prognostics monitor parameters to warn of impending problems.

Delphi Corp.
Three-stage rollover sensor

Delphi’s three-stage rollover sensor system first provides rollover warning, then mitigation and, finally, protection. A J1939 communication bus relays all the critical data relating to rollover to the vehicle safety systems. Rollover detection is based on an algorithm.

The sensor is integrated into the vehicle’s safety system. Any of the system’s functions can be engaged as necessary to prevent the rollover. As the vehicle approaches a rollover condition, the system first gives an audible or visual warning. If the vehicle continues to approach rollover, it first cuts fuel, then engages the engine brake and, finally, engages the braking via the ABS. This slows the vehicle, reducing the lateral acceleration, reducing the chance that the vehicle will roll over.

If rollover becomes likely, the system can mitigate the situation by engaging a restraint such as a rollbar or seatbelt pretensioner to help protect the driver. An air curtain can be deployed in the event rollover occurs.

Delphi Corp.
Headway Alert, Forewarn Smart Cruise Control

Delphi Headway Alert uses a 76 GHz radar-based sensor mounted behind the truck’s grille. It scans the road ahead and to either side to identify any object in the truck’s path, and can detect objects as far as 402 feet away.

The multipurpose sensor can be used for headway alert, collision warning, smart cruise control and pre-crash sensing. It warns the driver at its minimum warning level when he is following too closely for the speed. If a crash is imminent, it can be used to deploy any protective devices on the truck. If its view is blocked, the system warns the driver of the problem. Warnings can be audible, visual or tactile. Since radar penetrates dirt, ice, rain and fog, it will work under almost any conditions of weather or daylight.

Delphi Forewarn Smart Cruise Control (SCC) maintains the cruise control speed setting until a slower vehicle is detected ahead. It then will use throttle control or, if necessary, limited braking to slow the vehicle and follow at a distance that maintains the number of seconds between the vehicles the driver has selected. It will resume the set speed when the lane ahead becomes clear. A yaw sensor enables it to track vehicles ahead, even in curves.

The system can calculate that a crash is imminent and trigger in-cab driver protection devices or apply active braking. Forewarn also can be equipped with Side Alert, a 24 GHz dual beam radar designed to help drivers detect objects difficult to see in the side mirrors.

VORAD and SmartCruise

Eaton VORAD’s (Vehicle On-Board RADar) EVT-300 warns the driver of potential hazards ahead – like slower moving vehicles – giving him time to take evasive action.

The system transmits radar signals from both the front and side of the truck. When the front sensor detects a hazard, the dash display unit emits a combination of lights and audible tones. The tones come at decreasing intervals as following time decreases. It warns the driver of objects up to 344 feet ahead and, with an internal turn rate sensor, can distinguish between trucks in the same lane and those in adjacent ones, even in a curve.

The VORAD side sensor indicates objects in the blind spot along either side. Its display unit is mounted in the driver’s line of sight with the applicable side mirror. The display provides a visual warning of a hazard and, when direction signals are on, an audible one.

Eaton SmartCruise is available with the EVT-300 CWS. It joins engine and transmission electronics with collision warning technology to maintain preset speed and following distance. The system works normally until the following time (based on vehicle speed and distance) for a vehicle ahead drops below a pre-set parameter. The system will defuel the engine, engage the engine brake and even downshift an automated transmission to lower vehicle speed. As soon as the lane is clear, the set cruise speed will be resumed.

Power Linx
Power Line Vision System

Power Linx makes side vision cameras that use existing power wiring (via power line carrier technology) to transmit live images. When mounted on the side of the tractor, the camera makes the blind spot areas completely visible. The flat-screen monitor mounts on the dash or anywhere in the cab to avoid interfering with visibility. All the cameras are equipped with night vision (reflective infrared) technology.

The cameras offer a wide field of view and provide live, real-time video.

Safety Vision
SideVision SVCLCD-65-620

A SideVision camera mounted at the top, side or bottom of a vehicle’s sideview mirror captures an enhanced view of the immediate environment. This view is displayed on an LCD monitor inside the cab and enables the driver to see the full lanes of traffic on either side of his vehicle. This increases the accuracy of their lane changes and maneuvers in tight spaces.

The company says the camera gives crisp reproduction so the image won’t wash out, even in the brightest sunlight. Its infrared illumination provides enhanced vision at night or in any situation where there is limited light. It has built-in audio capability, allowing the driver to hear a warning or instruction from a helper on the ground.