Nonlinear control unit for a multi-degree-of freedom manipulator

Claim 2

A control unit for a multi-degree-of-freedom manipulator having a motor actuator (11, 32) by which an output torque is produced through each joint shaft (21), which comprises: torque sensing means (17, 51) for detecting the force exerting on each joint shaft (21); and operational means (71) for adding first and second correction values to input signals to the motor actuator(11, 32) in accordance with a torque signal produced from said torque sensing means (17, 51).

Claim 3

The control unit for a multi-degree-of-freedom manipulator as claimed in claim 1 wherein the first correction value to be applied to one input of the operational means (71) is equal to the torque signal (τ) divided by a reduction gear ratio (N) of the motor actuator side.

Claim 4

The control unit for a multi-degree-of-freedom manipulator as claimed in claim 1 wherein the second correction value to be applied to the other input of the operational means (71) is equal to the torque signal (τ) divided by a spring constant (KG) of the joint shaft (21).

Claim 5

A control unit for a multi-degree-of-freedom manipulator and having a motor link system (30) including a motor (32) for producing an output torque of each joint shaft (21) actuator and a motor rotational angle position control system (40), which further comprises: a non-linear and interference force compensation control system (50) having a torque sensor (51) for detecting a torque (τ) exerting on each of the joint shafts (21) and a first operator (53); a flexure and vibration compensation control system (60) having a second operator (61), a first correction value being produced through said first operator (53) which multiplies a torque signal (τ) produced from the torque sensor (51) by a reciprocal of a reduction gear ratio (1/N), a second correction value being produced through said second operator (61) which multiplies the torque signal (τ) produced from the torque sensor (51) by a reciprocal of a spring, constant ((1/KG) of each joint; and operational means (71) for adding the first and second correction values to input signals to the motor actuator (32).

Claim 6

A control unit for a multi-degree-of-freedom manipulator and having a motor link system (30) including a motor (32) for producing an output torque of each joint shaft (21) actuator and a motor rotational angle position control system (40), which further comprises: a non-linear and interference force compensation control system (50) having a torque sensor (51) for detecting a torque (τ) exerting on each of the joint shafts (21) and a first operator (53); a flexure and vibration compensation control system (60) having a second operator (61), a first correction value being produced through said first operator (53) which multiplies a torque signal (τ) produced from the torque sensor (51) by a reciprocal of a reduction gear ratio (1/N), a second correction value being produced through said second operator (61) which multiplies the torque signal (τ) produced from the torque sensor (51) by a reciprocal of a spring, constant ((1/KG) of each joint; and operational means (71) for adding the first and second correction values to input signals to the motor actuator (32).

Claim 7

The control unit for a multi-degree-of-freedom manipulator as claimed in claim 4 wherein said flexure and vibration compensation control system (60) further comprises a third operator (F2) for producing an operational signal in accordance with the second correction value, an adder (63) for adding a target value of a link angle (ϑer) and the second correction value as an actual twist angle (e), and a fourth operator (65) for producing a target value of the motor angle (ϑmr) multiplied by the reduction gear ratio of N.

Claim 8

The control unit for a multi-degree-of-freedom manipulator as claimd in claim 4 wherein said motor rotational angle position control system (40) comprises an angle sensor (43) for detecting an actual rotational angle (ϑm) of the motor actuator (32) and a second adder (41) for adding the target value of the motor angle and the actual motor rotational angle signal from the angle sensor (43).

Claim 9

The control unit for a multi-degree-of-freedom manipulator as claimed in claim 4 wherein said operational means (71) comprises a third adder (71) for adding an output signal from the second adder (41) and said first and second correction values.

Claim 10

The control unit for a multi-degree-of-freedom manipulator as claimed in claim 4 wherein said motor link system (30) further comprises a fourth adder (72) for adding an output signal from the third adder (71) and a feedback signal of (-τ/N).

Claim 11

The control unit for a multi-degree-of-freedom manipulator as claimed in claim 5 wherein said third operator F2 is a PID functional operator.