Seeking a Smoother Ride, Whether You Drive or Your Autonomous Car Does

The obstacle course was a series of speed bumps in a parking lot at the headquarters of ClearMotion, a supplier of high-tech chassis parts for production cars. The challengers were a late-model Mercedes-Benz and a 2016 BMW 535i equipped with the company's technology -- an electrically powered hydraulic device meant to complement the venerable shock absorber and keep the passenger compartment as level as possible. ClearMotion's technology greatly smoothed the way, significantly reducing not just the movement up and down, but also the right-left lurch from bumps on either side. And while the system doesn't make speed bumps obsolete, its goal is to become the kind of system that car owners won't be able to live without once self-driving technology turns them from drivers into passengers. Shakeel Avadhany, the founder and chief executive of ClearMotion, said he had been inspired by the ride in Japanese bullet trains, which can reach 200 m.p.h. with little sensation of movement.