When you slam on your brakes unexpectedly while driving, do you worry that your car may not stop? Do you wonder if your airbag will actually deploy correctly, given the infrequency of its use, or if your door might spring open during a collision, exposing your body as your car careens out of control?

As a nation with highways jammed with drivers, most of us don't realize what sort of technology goes into safety systems on the cars we drive, such as brakes, steering and stability. We know they are probably expensive but short of that, as long as the safety system works, most of us are happy. When we lease or purchase a new vehicle, we typically assume it is safe to drive, since it has passed federal and state regulations.

But the work in developing the dependable technology that helps a car stop or glide safely and smoothly over rough terrain is complex, highly sophisticated and very expensive for automakers to incorporate into your vehicle. Kettering University's Juan Pimentel of the Electrical and Computer Engineering Dept. is fully aware of how difficult it is to develop dependable systems in cars. Dependability is an important concept that involves safety, reliability, availability and security. What makes his most recent research exciting is that his dependable, simple and cost-efficient system not only works well with traditional combustion engines, but also with hybrid vehicles and electric propulsion systems, which may one day replace the cars we drive today.

Over the past several years Pimentel has worked in the field of controller area networks (CAN) to develop an architecture and protocol for highly dependable (otherwise known as safety-critical) systems in automobiles. By definition, controller area networks work in conjunction with other electronic systems inside cars for various operations, such as braking and steering. Unfortunately, there are no dependable systems on the market that are simple and inexpensive. So Pimentel went about researching and developing an architecture and protocol he calls FlexCAN, which is based on CAN protocol and is suitable for highly dependable systems. Pimentel also integrated SafeCAN into his system, which deals with error detection and fault management of buses and nodes used to communicate electronically with other system components inside a vehicle.

What does all this techno mumbo jumbo mean? In simple terms, Pimentel has developed a highly dependable system that is simpler and cheaper for automakers to incorporate into their vehicle while sustaining the high quality of research necessary to create systems to protect drivers in case of emergencies. His work enhances the current CAN protocol used in the industry today, which is very different from what other companies and firms are currently doing. His architecture and protocol rely on commercially over the shelf (COTS) CAN components available on the market. This is vastly different from other companies as they work in developing safety critical systems from scratch, which is costly and often times passed on to the automaker and thereby the consumer, due to the complexity involved in creating a system that works effectively.

"To make these systems work efficiently and effectively, one needs an approach that considers all aspects of development and usage to achieve dependability at various levels."

For Pimentel, the CAN protocol available in today's market still holds great potential and opportunity. "I want to build on and enhance what's already available in terms of CAN systems, since the basic operation of these systems works well," he explained. "But I am going about utilizing these components with a little different twist. In previous years, you had specialists who worked in various capacities for safety critical systems, but not all specialists knew what the other was doing. Thus, they didn't have a full understanding of how these systems worked in conjunction with each other in the broad range of operation, for example, in automotive applications, or how their work in this field affected the work of other engineers."

To address this trend, which has several pitfalls in Pimentel's eyes, he approached the development of his system and protocol (called FlexCAN and SafeCAN) from an interdisciplinary perspective, or what others might term a holistic approach. This method is new to safety critical systems development, one that utilizes Pimentel's interdisciplinary training and experience. "To make these systems work efficiently and effectively, one needs an approach that considers all aspects of development and usage to achieve dependability at various levels," he said. "FlexCAN considers advances and component availability in the following fields: application domain, embedded systems, protocols and networks, safety and reliability, real-time systems and systems engineering."

The development of FlexCAN began three years ago and is now at a stage that allows use of the system for evaluation purposes in the design and incorporation of safety critical systems. In the past few years, some of the projects that utilized various aspects of FlexCAN include simulation, target implementation, diagnostics, network management, testing and verification. On April 28, Pimentel held a demonstration in Kettering's Computer Networking Laboratory that involved a steer-by-wire system built on FlexCAN and SafeCAN. Representatives from the Society of Automotive Engineers (SAE) attended the demonstration and have shown considerable interest in standardizing this protocol. If this proves to be the case, Pimentel said a large percentage of future cars might use the protocol, which "has tremendous, positive impact and implications for the University."

More than 20 representatives from such firms as Ford, Bosch, dSPACE, EDS, Delphi, Lear, Vector CANTech Inc., Ricardo, and USDI attended the demonstration. John Kaniarz, a 2003 Computer Engineering graduate from Troy, Mich., currently employed by GM, collaborated with Pimentel on the development of SafeCAN and continues working with him on the ongoing development and research associated with FlexCAN's potential. He became interested in this project during his spring 2003 capstone project. Other researchers at the University of Aviero, Portugal and the University of Padova in Italy are also collaborating with Pimentel on further analysis and development of FlexCAN and SafeCAN.

Learn more about this important research and see how this new development will impact the automotive industry at a time when other efforts achieve similar objectives based on technology developed from scratch.

Written by Gary J. Erwin
810-762-9538
gerwin@kettering.edu