Putting wheelchair users in the driving seat

A system that combines robotics, laser and wireless technologies promises to make it safer and cheaper for wheelchair users to drive a car without significant vehicle modification.



Engineers at Lehigh and Carnegie Mellon universities, worked with Freedom Science and Freedom Lift to develop the Automatic Transport and Retrieval System (ATRS). Scheduled to go on sale next spring, ATRS allows wheelchair users to get in and out of their vehicles, stow and retrieve their chairs, and drive while sitting in standard automobile seats.



ATRS contains three key components: an articulated power seat that extends outside the vehicle to facilitate wheelchair-to-seat transfers, a power lift platform, and a ‘smart’ wheelchair system.



Users move the powered wheelchair next to the driver’s side of their vehicle. Using a remote-control device similar to a key fob, they open the vehicle door and direct the vehicle to lower the driver’s seat alongside the wheelchair. They then slide over from the wheelchair into the driver’s seat. Once in the driver’s seat, they deploy the power lift platform from the rear of the vehicle through the touch of a button.



Using a joystick for remote control, they then guide the empty wheelchair to the rear of the van. There, the chair is switched to autonomous mode, and drives itself onto the lift platform using position feedback from an integrated laser system at a rate of 10 times per second. The lift platform then raises and stows the chair in the back of the van.



At this point, users press another button to raise the driver’s seat, in which they are sitting, up into the van. The driver’s seat is then restored to its normal driving position and secured.



The laser system on the rear lift platform takes corrective action if an obstruction or slick spot causes the wheelchair to veer off course as it moves toward the platform. If it is not entirely sure that the docking will be successful, it will back the chair up and perform corrective action.



A camera above the platform lift, working in tandem with a human-robot user-interface computer on the ATRS dashboard, lets the driver know when to use the joystick to close the rear hatch of the ATRS-equipped vehicle.



Once the chair has been stowed, two hooks on the rear platform grip a plough bar on the chair and lock it in place.



To help drivers move from wheelchair to car seat, the ATRS Freedom Seat is fully articulated. Its adjustable height allows drivers to always move down when they slide from wheelchair to car seat or vice versa.



The system’s modularity enables the ATRS to accommodate almost all sizes and models of wheelchairs and to offer easy upgrades for wheelchair users who have progressive diseases.



Next year Freedom Sciences is planning to develop an advanced ATRS for wheelchair users who have difficulty sliding themselves from the chair to the car seat. The new system will be fully automated, using a small ‘smart’ camera instead of a joystick.