With millions of daily commuters in the United States, and nearly 80 per cent of them driving alone to work each day, suburbanites and city dwellers may soon have a new alternative to get them out from behind the steering wheel. Bill Diong, associate professor of electrical engineering, Ying Wang, associate professor of mechatronics engineering, and Jidong Yang, assistant professor of civil engineering -- all faculty in Kennesaw State University's Southern Polytechnic College of Engineering and Engineering Technology -- are exploring a viable solution to make bus travel more appealing to commuters and more cost-effective for communities. Their research is funded by a $175,000 grant from the Georgia Department of Transportation. Bus rapid transit (BRT) is a bus-based public transport system designed to improve capacity and reliability relative to a conventional bus system. It is used in high-volume metro areas to transport passengers quickly and on time to their destinations, and is one way to reduce highway congestion and the number of lone commuters. The concept to improve BRT being developed by Diong and his research team is centred on a new type of bus. The new bus design was devised to make bus transport more attractive and affordable and lead to increased transit use and reduced car traffic. "Our concept is aimed at making improvements that would convince more people to not use their cars for their work commutes and choose instead to take a BRT bus," said Diong. He explained that more people want a transit option that provides speedy commutes, and convenient and on-time schedules, which is not guaranteed by conventional bus systems.

Slim Modular Flexible Electric Bus

[caption id="attachment_35292" align="alignright" width="300"]Slim Modular Flexible Electric Bus CLICK TO ENLARGE The SMFe-bus is a semi-autonomous vehicle, where each driverless module is programmed to follow the module preceding it[/caption] The team's proposed bus, called the Slim Modular Flexible Electric Bus (SMFe-bus), however, has a slimmer frame that can travel in narrower dedicated lanes. With gull-wing doors and three-seat wide rows, the SMFe-bus has a lead module with a human driver and a few driverless modules, strung together without being physically attached to the lead vehicle or each other. Each module is self-propelled by in-wheel electric motors. "It is a semi-autonomous vehicle, where each driverless module is programmed to follow the module preceding it," said Diong. What makes their BRT concept different is that the modules are uncoupled, leaving a small gap of space between each self-driving unit. The modules are programmed to coordinate their spacing and alignment in a 'virtually coupled' fashion, which allows for flexible bus capacity, he added. Modules can be easily added or removed from the vehicle over the span of a day, in tune with varying passenger demand. Sensors gauge the lead vehicle's movements, and the principle, said Diong, is for them to stay fairly close, but far enough apart so if the lead module's driver brakes suddenly, the autonomous modules can respond quickly to avoid colliding with each other. With safety features built into their system, the modules can quickly change speed and direction. As part of the research, Wang is working on the autonomous vehicle technology, specifically the virtual coupling technology that blends the camera and sensor technologies with intelligent control technology. "Our prototype explores the neural network and benefits from artificial intelligence technology, and how a machine, or robot, learns how to accept information from humans," said Wang. He explained that significant progress in computer vision technology, such as cameras to classify objects, and the speed of today's graphics processing units are improving high-level decision-making for the autonomous vehicle industry.

Narrower dimensions and adjustable capacity

BRTs already have signal priority -- the ability to change traffic lights to favour their pathway as they approach intersections -- which aid in on-time scheduling for the transit system, said Yang, who is working on the feasibility aspects of their concept and the infrastructure design components to support its operations. The feasibility study will look at two potential BRT corridors in the metro Atlanta area. Although the semi-autonomous SMFe-bus will cost more than a traditional bus, the team's new BRT concept, with its narrower dimensions and easily adjustable capacity, could result in substantial cost savings in land acquisition, roadway construction and service operation, according to the research team. This could possibly mean as much as a 20 percent cost savings on a BRT project in cities with dense populations and pricey real estate, an estimate which the team is working to refine, according to Diong. He added that keeping BRT costs low is crucial since taxpayers are only interested in funding transportation projects that yield sufficient bang for their buck. As part of the team's research, four undergraduate and three graduate engineering students are also working to develop a prototype SMFe-bus, which is being designed to ultimately operate at a top speed of 105 kilometres per hour. A provisional patent has been filed for the team's SMFe-bus concept.