Robot arm with weight compensation

A torque compensation unit for a robot, the robot having a robot arm and a drive, the unit comprising:

• a stationary housing;
• a magnet configuration mounted to said housing separate from the drive, said magnet configuration having an inner surface defining a cavity having a clearance width, said magnet configuration generating a magnetic field penetrating through said cavity;
• an armature disposed for displacement within said cavity, said armature made from a non-magnetized magnetic conducting material of high permeability, wherein said magnetic field permeates said armature to pull said armature into said cavity;
• and
• means for connecting said armature to the robot arm to provide torque compensation for at least one motional degree of freedom of the robot arm.

A method for torque compensation of a robot arm, the robot arm having a drive, the method comprising the steps of:

• a) mounting a magnet configuration to a stationary housing separate from the drive, said magnet configuration having an inner surface defining a cavity having a clearance width, said magnet configuration generating a magnetic field penetrating through said cavity;
• b) disposing an armature for displacement within said cavity, said armature made from a non-magnetized magnetic conducting material of high permeability, wherein said magnetic field permeates said armature to pull said armature into said cavity;
• and
• c) connecting said armature to the robot arm to provide torque compensation for at least one motional degree of freedom of the arm.