Sensor fusion enables Cadillac safety advancements

The all-new 2013 Cadillac XTS, the most technologically advanced production car the luxury brand has ever offered, introduces an advanced active safety and driver assistance system, a significant milestone toward the development of self-driving vehicles.

Coming this fall to XTS, the available Driver Assistance Package is the first General Motors system of its kind to use sensor fusion, which enables integration of a broad range of sensing and positioning technologies that can alert drivers of road hazards and help them avoid crashes.

The system’s use of radar, cameras and ultrasonic sensors enables advanced safety features, including:

YRear Automatic Braking

YFull-Speed Range Adaptive Cruise

Control

YIntelligent Brake Assist

YForward Collision Alert

YSafety Alert Seat

YAutomatic Collision Preparation

YLane Departure Warning

YSide Blind Zone Alert

YRear Cross Traffic Alert

YAdaptive Forward Lighting

YRear Vision Camera With Dynamic

Guidelines

YHead Up Display

“We believe sensor fusion will enable future active safety systems to handle a greater number of inputs to provide 360 degrees of crash risk detection and enhanced driver assist features,” said Bakhtiar Litkouhi, GM Research and Development lab group manager for perception and vehicle control systems.

“A system that combines the strengths of multiple sensing technologies and expertly manages those inputs can provide advisory, warning, and control interventions to help drivers avoid collisions and save lives,” Litkouhi said.

Sensor fusion also is a building block in the development of semi-autonomous and fully autonomous vehicles, which are designed to maintain lane position and adapt to traffic environments. It is envisioned that more sophisticated self-driving technology, that could enable semi and fully autonomous driving, will be available by the end of the decade.

GM’s leading-edge work on sensor fusion draws on its experience with The Boss, a fully autonomous Chevrolet Tahoe developed by GM, Carnegie Mellon University and other partner companies, and named for GM R&D founder Charles F. “Boss” Kettering. In 2007, The Boss navigated 60 miles of urban traffic, busy intersections and stop signs in less than six hours to win the Defense Advanced Research Projects Agency (DARPA) Urban Challenge competition.

Sensor fusion development also is bolstered by GM’s work on the EN-V, three semi-autonomous electric concept vehicles unveiled at the 2010 Shanghai World Expo. By combining GPS with vehicle-to-vehicle communications, distance-sensing and object detection technologies, EN-V can be driven both manually and autonomously, the latter allowing it to automatically select the fastest route based on real-time traffic information.

Among the technologies that GM is looking to develop for future active safety systems is LIDAR, a light detecting and ranging technology that can measure the distance to a vehicle or object by illuminating it, often using pulses from alaser. Although LIDAR is no replacement for driver vision, it can become another set of eyes when visibility has deteriorated due to inclement weather or darkness. When combined with radar, cameras and ultrasonic sensors, LIDAR has potential crash avoidance capability.

A more advanced positioning system, using more accurate GPS and digital mapping, also is expected to play an important role on future active safety systems because it helps locate vehicles in relation to one another. While GPS effectiveness can be limited in urban canyon environments where high-rise buildings can interfere with satellite signals, the technology is still considered an asset when “fused” with other sensing and positioning technologies.

“No sensor working alone provides all the needed information. That’s why multiple sensors and positioning technologies need to work together synergistically and seamlessly,” Litkouhi said. “Sensor fusion will help facilitate that.”