Exoskeleton with kinesthetic feedback and robotic control

• US 5,516,249 A
• Filed: 05/10/1994
• Issued: 05/14/1996
• Est. Priority Date: 05/10/1994
• Status: Expired due to Fees

• Current Assignee: Optical Research Associates (Synopsys Incorporated)
• Original Assignee: Optical Research Associates (Synopsys Incorporated)
• Inventors: Brimhall, Owen D.
• Primary Examiner(s): Underwood, Donald W.
• Application Number:
  US08/241,157
• Time in Patent Office: 735 Days
• Field of Search: 414/5, 364/806
• US Class Current: 414/5
• CPC Class Codes: B25J 3/04 involving servo mechanisms servo-actuated heads B25J15/02
• CPC Class Codes: B25J 9/0006 Exoskeletons, i.e. resembling a human figure
• CPC Class Codes: E02F 9/2008 Control mechanisms in the form of the machine in the reduced scale model

Abstract

A control apparatus and method for controlling a remote actuator, the control apparatus having a kinesthetic feedback system for providing a kinesthetic sensation to the operator as a physical sensation representative of the resistive forces encountered by the remote actuator. The control apparatus is configured to be releasably mounted to the hand of the operator with control modules supported at preselected joints of the hand. The control modules sense changes in the angular orientation in the respective joints and generate a control signal as a function of the change. This control signal is used to drive the corresponding actuator. Each actuator includes a sensor to sense resistive forces encountered by the actuator and generate a response signal as a function of the resistive forces. A magnetostrictive clutch mechanism on the control module is controlled by the response signal to provide a resistive force against movement of the control module thereby providing a kinesthetic sensation to the hand of the operator.

Claims

1. A control apparatus having kinesthetic feedback comprising:

first sensor means for sensing relative movement of a human appendage, said first sensor means producing a first signal as a function of said relative movement, said first sensor means comprising a lever pivotally mounted at a pivot to the human appendage so that movement of the human appendage causes a corresponding movement of said lever, said first sensor means further including a sensor on said pivot for sensing rotation of said pivot, said sensor producing said first signal;

mounting means for mounting said first lever to the human appendage;

an actuator located a distance from said first sensor means;

first processor means for processing said first signal and transmitting said first signal to said actuator, said first processor means driving said actuator as a function of said relative movement of the human appendage;

resistive means mounted to said mounting means for imparting a kinesthetic feedback to the human appendage, said resistive means comprising a clutch means on said pivot, said clutch means comprising a clutch actuator for resisting movement of said lever;

second sensor means for sensing a resistive force encountered by said actuator upon movement of said actuator, said second sensor means producing a second signal;

second processor means for transmitting said second signal to said resistive means, said second signal means causing said resistive means to impart said kinesthetic feedback to the human appendage, said kinesthetic feedback being a function of said resistive force; and

a magnetostrictive rod driven by said second signal, said magnetostrictive rod being coupled to said clutch means to operate said clutch actuator as a function of said second signal.

2. The control apparatus defined in claim 1 wherein said control apparatus includes a plurality of first sensor means, each of said plurality of first sensor means being mounted to a separate portion of the human appendage by said mounting means so that each of said plurality of first sensor means is driven independently by the human appendage.

3. The control apparatus defined in claim 2 wherein said control apparatus includes a plurality of said actuators and corresponding resistive means, each of said plurality of actuators including a second sensor means for generating a plurality of second signals, said plurality of said second signals connected to said second processor means for transmitting said second signals to said corresponding plurality of said resistive means for creating a plurality of kinesthetic feedback to the human appendage.

4. A control apparatus operable by a human appendage and including kinesthetic feedback to the human appendage comprising:

a position sensor mounted to the human appendage for sensing motion of the human appendage, said position sensor producing a first signal as a function of said motion, said position sensor comprising a lever pivotally mounted on a pivot to the human appendage so that movement of the human appendage creates a corresponding movement of said lever, said position sensor including a movement sensor on said pivot for sensing said movement of said lever, said pivot including a clutch actuator on said pivot, said clutch actuator comprising said kinesthetic feedback by creating rotational resistance against said pivot, said rotational resistance being sensed by the human appendage as said kinesthetic sensation, said pivot comprising a housing having a disc pivotally mounted therein with said lever extending outwardly from said disc, said clutch including a pressure plate and a magnetostrictive rod in abutment with said pressure plate, said magnetostrictive rod pushing said pressure plate against said disc to impede rotational movement of said disc, said magnetostrictive rod being surrounded by an electromagnetic coil, said electromagnetic coil receiving said second signal to cause elongation of said magnetostrictive rod, said elongation being a function of said second signal;

an actuator at a remote location from said position sensor, said actuator being driven in response to said first signal;

a resistance sensor for sensing resistive forces encountered by said actuator as said actuator is being driven in response to said first signal, said resistance sensor producing a second signal as a function of said resistive forces; and

a kinesthetic feedback on said position sensor said kinesthetic feedback being operable by said second signal to impart a kinesthetic sensation to the human appendage as a function of said second signal.

5. The control apparatus defined in claim 4 wherein said housing includes said position sensor mounted in abutment to said disc, said position sensor sensing the rotational movement of said disc to produce said first signal as a function of said rotational movement.

6. A method for receiving a tactile sensation through a manipulation apparatus, the tactile sensation being representative of a resistive force encountered by a remote actuator controlled by the manipulation apparatus comprising the steps of:

preparing a position sensor for sensing changes in the relative position of a lever arm mounted to a joint of a human appendage, said position sensor sending position signals as a function of changes in said relative position;

mounting said position sensor to the human appendage;

moving the appendage thereby causing said position sensor to send position signals;

controlling movement of said remote actuator with said position signals from said position sensor;

sensing resistive forces encountered by said remote actuator during said movement;

producing a resistance signal as a function of said sensing resistive forces;

placing a magnetostrictive rod adjacent said lever arm, said magnetostrictive rod being surrounded by an electromagnetic coil;

transmitting said resistance signals to said coil; and

extending said magnetostrictive rod with said resistance signals causing a retarding movement of said lever arm by the human appendage thereby providing a tactile sensation to the human appendage as a function of said resistive forces.

7. The method defined in claim 6 wherein said preparing step further includes preparing a plurality of said position sensors and said mounting step comprises mounting each of said position sensors to different joints of the human appendage, the human appendage being a human hand and the joints being on fingers of the hand.

8. The method defined in claim 7 wherein said mounting step comprises preparing a glove-like assembly and attaching each of said position sensors to preselected locations on said glove-like assembly thereby placing each of said position sensors over preselected joints of the hand.

9. The method defined in claim 6 wherein said extending step comprises resisting movement of said lever joint of said position sensor by applying a braking action on said lever joint.

10. The method defined in claim 9 wherein said placing step comprises obtaining said magnetostrictive rod and placing said magnetostrictive rod in contact with said lever arm and surrounding said magnetostrictive rod with said electromagnetic coil, said transmitting step including directing said resistance signals to said electromagnetic coil thereby causing said magnetostrictive rod to create said braking action on said lever arm, the human appendage sensing said braking action as a function of said resistive forces encountered by said remote actuator.