Travelers aboard high-speed passenger trains aren’t fond of being flung across the train car each time it rounds a corner, so the cars come equipped with tilting suspension systems that allow them to lean into each turn to compensate for centripetal force. As passenger trains gets faster and faster, demand for more adaptive, reliable suspension systems will continue to rise. And by Electrical and Computer Engineering Associate Professor Paul Milenkovic’s calculations, the future of tilting suspension systems–or adaptive suspension systems in general, even for cars and trucks–may be more rooted in the theorems of the past than in high-tech robotics.
Studying the work of 18th- and 19th-century mathematicians and astronomers like Sir Robert Ball, Julius Plücker and Michel Chasles, Milenkovic has simplified their complicated calculations in order to apply them more easily to systems using mechanical linkages—any series of connected parts with a defined range of motion—to control how a vehicle moves. “There’s still a role for a kind of automation which is a result of geometric arrangements of linkages, rather than programming of a computer,” says Milenkovic.
The result could be simpler, more efficient suspension systems for myriad vehicles.
By improving what vehicle engineers can predict and design for mathematically, Milenkovic believes his research could improve the performance of passive tilting suspensions–like those found in Talgo trains or the UAC Turbotrain–to the point that they could match the speed and performance found in active suspension systems that require control from servo-guided robotics. “Something that is done passively has potentially lower costs and lower maintenance, since you don’t have to see if the system has lost power or its hydraulic seals,” he says.
Beyond the rails, Milenkovic’s work has implications for any system that controls motion through a series of linkages, which could range from consumer autos to military vehicles like tanks. More precisely designed and controlled vehicle suspensions could enable vehicles that are more power efficient and cost effective to produce, but remain extremely safe.