2-DOF planar direct-drive robot similar to MIT-MANUS (red dashed) and a 1-DOF linear motion robot moving the endpoint of the 2-DOF planar DD robot (blue dots). A Force/Torque (F/T) sensor was attached at the endpoint of the 2-DOF DD robot. The 1-DOF robot was fixed to the F/T sensor and pulled the 2-DOF robot at a…