MTS Systems Corp., a global supplier of high-performance test systems and position sensors, has developed a high-precision vehicle guidance system for the Minnesota Valley Transit Authority (MVTA) Bus on Shoulder transportation program, utilizing a licensed GPS technology developed by the University of Minnesota. The advanced DAS (Driver Assist System) provides feedback to the driver regarding lane position – via graphic driver alert displays, virtual mirror, vibrating seat and actuated steering – based on the highly accurate technology.
The MVTA Bus on Shoulder program, made possible by a Safety Resiliency and Emergency Response grant from the FTA, allows buses to use shoulders on the authorized freeways and major arterial streets during peak congestion periods. The program provides a cost-effective solution to reduce congestion in general-purpose traffic lanes while reducing fuel consumption and air pollution.MVTA's primary goal for the DAS is to enhance driver confidence when operating buses on shoulders, particularly during bad weather when visibility is hampered. Secondary goals include reduced travel times, increased reliability, safety, and customer satisfaction. The MVTA installed an earlier release of DAS into ten of its buses and will now implement the second-generation DAS into eleven more vehicles, as well as upgrading the previous ten.
While conventional 'consumer grade' GPS is only accurate to seven to ten feet (two to three meters), the GPS technology employed in the MVTA solution enables position measurement down to just two to four inches (five to ten centimeters). The University of Minnesota-developed technology used by MTS, under license, was augmented to ensure vehicle position accuracy is maintained when GPS connectivity is lost due to travelling under overpasses or similar situations. Bus drivers can determine exactly where the vehicle is in relation to shoulder boundaries at all times. Seat vibration actuators alert the driver if the vehicle begins to depart from the shoulder and supplemental radar and LiDAR (Light Detection and Ranging) functions enhance safety by identifying possible obstructions that lie ahead.
"The Bus on Shoulder process helps to address the burgeoning traffic problems in cities without the cost and inconvenience of putting new road infrastructure in place," says Luther Wynder, the MVTA's Executive Director. "By equipping buses with Driver Assistance Systems, we can give bus drivers the confidence to travel on shoulders in a range of conditions, while ensuring the safety of passengers and other road users at all times."