PASCAL: Pediatric arm support robot for combined arm and leg training

Cerebral palsy (CP) occurs in over 2 out of 1000 live births and can impair motor control and cognition. Automated robotics systems are now able to assist upper- and lower extremity therapy for patients with CP. Existing robots, however, exercise either the upper or the lower extremities independent of each other, thereby neglecting the fact that many activities of daily living require coordination of gait speed with goal directed arm movements while maintaining postural stability. Our goal was therefore to create a robotic rehabilitation environment that would mimic real-life situations by allowing simultaneous exercise of upper and lower limbs. Due to its wide spread use in the clinical world, we chose to use the Lokomat gait orthosis as a gait robot and added a removable arm robot that could be integrated into the existing device. We designed, fabricated and assembled this novel arm support system and implemented position and force (impedance) control. This paper describes the development and design of the new arm robot, its integration into the Lokomat system and reports data of initial measurements in healthy subjects.