An interlocking bed and wheelchair has been developed by the Massachusetts Institute of Technology which could help disabled or elderly people to move from bed to chair without help. The electrically-powered wheelchair is designed to be used with a horseshoe-shaped bed, forming a system called Rhombus. It can be docked in the horseshoe section of the system and then lowered and flattened for it to form a part of the bed. The wheelchair can also respond to muscle movement and the speed and direction of the wheelchair can be controlled with a joystick.