Pneumatic human power amplifer module

• US 5,915,673 A
• Filed: 06/17/1997
• Issued: 06/29/1999
• Est. Priority Date: 03/27/1996
• Status: Expired due to Fees

• Current Assignee: Homayoon Kazerooni
• Original Assignee: Homayoon Kazerooni
• Inventors: Kazerooni, Homayoon
• Primary Examiner(s): MATECKI, KATHERINE A
• Application Number:
  US08/877,094
• Time in Patent Office: 742 Days
• Field of Search: 254/266, 254/270, 254/274, 254/331, 254/360, 254/361, 254/362, 212/331, 212/330, 212/338, 212/285, 414/2, 414/4, 414/5
• US Class Current: 254/270
• CPC Class Codes: B66C 1/62 comprising article-engaging members of a shape complementary to that of the articles to be handled
• CPC Class Codes: B66C 23/005 with balanced jib, e.g. pantograph arrangement, the jib being moved manually
• CPC Class Codes: B66D 3/18 Power-operated hoists
• CPC Class Codes: B66D 3/20 with driving motor, e.g. electric motor, and drum or barrel contained in a common housing
• CPC Class Codes: B66F 3/242 suspended jacks

Abstract

A pneumatic human power amplifier module is usable in conjunction with a wide variety of pneumatic actuators and lifting devices to provide a human power amplifier for lifting a load. The module includes an end-effector, an electronic controller and a pneumatic circuit. The end-effector contains a human interface subsection which is grasped by a human operator and a load interface subsection which engages the load to be lifted. A force sensor in the end-effector detects the force imposed by the operator on the end-effector and transmits a signal representing the magnitude of the force to the controller. The controller in turn sends a command to the pneumatic circuit, which controls the flow of air into the associated pneumatic actuator. The actuator drives the lifting device. The controller and the pneumatic circuit are arranged such that the lifting device and the operator share the burden of lifting the load, with the operator supplying a predetermined percentage of the total force required to lift the load regardless of the size of the load.

Claims

1. A pneumatic human power amplifier module for connection to a pneumatic actuator for driving a lifting device to lift or lower a load, said module comprising:

an end-effector for engaging the load, said end-effector including a sensor for detecting a human force on the end-effector;

a controller arranged to receive an output signal from said sensor; and

a pneumatic circuit attachable to said pneumatic actuator, said pneumatic circuit being arranged to receive an output signal from said controller and to control an air flow into and out of said pneumatic actuator such that said pneumatic actuator causes said lifting device to impose a device force on the load such that the total of said human force and said device force taken together causes the end-effector and the load to follow an operator'"'"'s hand as said operator manipulates said end-effector and said load.

2. The pneumatic human power amplifier module of claim 1 wherein said device force is larger than said human force.

3. The pneumatic human power amplifier module of claim 1 wherein said human force is equal to a predetermined percentage of said total of said human force and said device force.

4. The pneumatic human power amplifier module of claim 1 wherein said pneumatic circuit comprises a flow control proportional servovalve for controlling an air flow into and out of said pneumatic actuator.

5. The pneumatic human power amplifier module of claim 1 wherein said pneumatic circuit comprises a pressure control proportional servovalve for controlling the pressure of an air flow into and out of said pneumatic actuator.

6. The pneumatic human power amplifier module of claim 4 or 5 wherein said pneumatic circuit comprises an UP valve and a DOWN valve for overriding said proportional servovalve, said UP valve being operable manually to cause an air flow into said pneumatic actuator, said DOWN valve being operable manually to cause an air flow out of said pneumatic actuator.

7. The pneumatic human power amplifier module of claim 6 wherein said UP valve is connected in parallel with said proportional servovalve for manually controlling an air flow from a supply pressure to said pneumatic actuator.

8. The pneumatic human power amplifier module of claim 6 wherein said DOWN valve is connected in parallel with said proportional servovalve for manually controlling an air flow out of said pneumatic actuator to the ambient atmosphere.

9. The pneumatic human power amplifier module of claim 6 wherein said UP and DOWN valves are for allowing manual operation of said lifting device in the event of a failure of said controller and/or said sensor.

10. The pneumatic human power amplifier module of claim 6 wherein said UP and DOWN valves are for allowing manual operation of said lifting device in the event of an electric power failure.

11. The pneumatic human power amplifier module of claim 6 wherein said pneumatic circuit comprises a directional servovalve and said end-effector comprises a deadman switch, said directional servovalve providing an air passage between said proportional servovalve and said pneumatic actuator when said deadman switch is in a first position.

12. The pneumatic human power amplifier module of claim 11 wherein said directional servovalve provides an air passage between said pneumatic actuator and said UP and DOWN valves when said deadman switch is in a second position.

13. The pneumatic human power amplifier module of claim 12 wherein said UP and DOWN valves allow said pneumatic actuator to be operated manually when deadman switch is in said second position.

14. The pneumatic human power amplifier module of claim 11 wherein said directional servovalve is arranged to receive an output signal from said deadman switch.

15. The pneumatic human power amplifier module of claim 1 wherein said end-effector comprises a human interface subsection for interfacing with an operator and a load interface subsection for engaging a load.

16. The pneumatic human power amplifier module of claim 15 wherein said human interface subsection comprises a handle to be grasped by an operator.

17. The pneumatic human power amplifier module of claim 16 wherein said pneumatic circuit comprises a directional servovalve and said end-effector comprises a deadman switch, an output signal from said deadman switch actuating said directional servovalve so as to provide an air passage between said proportional servovalve and said pneumatic actuator when said deadman switch is in a first position.

18. The pneumatic human power amplifier module of claim 17 wherein said deadman switch is moved from a second position to said first position when an operator grasps said handle.

19. The pneumatic human power amplifier module of claim 15 wherein said human interface subsection further comprises a brace for engaging the operator'"'"'s forearm.

20. The pneumatic human power amplifier module of claim 19 wherein said brace encircles the operator'"'"'s forearm and is connected to two ends of said handle with a vertical hinge such that the operator can flex his or her wrist only in a horizontal plane when lifting a load with the end-effector.

21. The pneumatic human power amplifier module of claim 15 wherein said end-effector comprises a position sensor for detecting a relative position of said handle with respect to said load interface subsection, an output signal from said position sensor representing said relative position of said handle with respect to said load interface subsection.

22. The pneumatic human power amplifier module of claim 21 wherein said human interface subsection comprises a ball-screw arrangement for converting a linear motion of said handle relative to said load interface subsection into a rotary motion, said ball-screw arrangement comprising a nut portion and a screw portion.

23. The pneumatic human power amplifier module of claim 21 wherein said human interface subsection comprises a lead-screw arrangement for converting a linear motion of said handle relative to said load interface subsection into a rotary motion, said lead-screw arrangement comprising a nut portion and a screw portion.

24. The pneumatic human power amplifier module of claim 22 or 23 wherein said screw portion is rotatably held by the load interface subsection and said nut portion is constrained to move linearly along a major axis of said screw portion.

25. The pneumatic human power amplifier module of claim 22 or 23 wherein said nut portion is attached to said handle.

26. The pneumatic human power amplifier module of claim 22 or 23 wherein said position sensor comprises an angle-measuring device for measuring a rotation of said screw portion relative to said nut portion.

27. The pneumatic human power amplifier module of claim 26 wherein said angle-measuring device is selected from the group consisting of a rotary potentiometer, a rotary optical encoder, and a rotary magnetic encoder.

28. The pneumatic human power amplifier module of claim 22 or 23 wherein said end-effector comprises at least one spring for maintaining said handle in an equilibrium position when no force is imposed on said handle by an operator.

29. The pneumatic human power amplifier module of claim 15 wherein said load interface subsection is designed for attachment to an endpoint of said lifting device.

30. The pneumatic human power amplifier module of claim 15 wherein said load interface subsection comprises a mechanism for engaging a load.

31. The pneumatic human power amplifier module of claim 30 wherein said mechanism for engaging a load comprises at least one suction cup.

32. The pneumatic human power amplifier module of claim 30 wherein said mechanism for engaging a load comprises at least one hook.

33. A human power amplifier apparatus comprising:

a lifting device;

a pneumatic actuator; and

a pneumatic human power amplifier module coupled to said pneumatic actuator for driving said lifting device to lift or lower a load, said module comprising;

an end-effector for engaging the load, said end-effector including a sensor for detecting a human force on the end-effector;

a controller arranged to receive an output signal from said sensor; and

a pneumatic circuit coupled to said pneumatic actuator, said pneumatic circuit being arranged to receive an output signal from said controller and to control an air flow into and out of said pneumatic actuator such that said pneumatic actuator causes said lifting device to impose a device force on the load such that said human force and said device force together lift the load.

34. The human power amplifier apparatus of claim 33 wherein said human force is equal to a predetermined percentage of a total of said human force and said device force.

35. A method by which a human operator manipulates a load comprising the steps of:

gripping an end-effector with said operator'"'"'s hand;

using the end-effector to engage the load;

applying an operator force against said end-effector;

measuring said operator force;

using said measured operator force to control a flow of air into a pneumatic actuator; and

controlling said flow of air into said pneumatic actuator such that said pneumatic actuator causes a lifting device to transmit a device force to said end-effector such that said end-effector and said load follow said operator'"'"'s hand.

36. The method of claim 35 wherein the step of controlling comprises controlling said flow of air such that said operator force is equal to a predetermined percentage of a total of said operator force and said device force.

37. The method of claim 35 wherein the step of controlling comprises controlling said flow of air such that said operator force is less than said device force.

38. The method of claim 35 wherein the step of controlling said flow of air comprises providing a first signal representative of said measured operator force to a computer and using said computer to generate a second signal to a proportional servovalve.

39. A human power amplifier apparatus comprising:

a lifting device;

a pneumatic actuator; and

a pneumatic human power actuator module coupled to said pneumatic actuator for driving said lifting device to lift or lower a load, said module comprising;

an end-effector for engaging the load, said end-effector including a sensor for detecting a human hand motion in the end-effector;

a controller arranged to receive an output signal from said sensor; and

a pneumatic circuit coupled to said pneumatic actuator, said pneumatic circuit being arranged to receive an output signal from said controller and to control an air flow into said pneumatic actuator such that said pneumatic actuator causes said lifting device to impose a device force on the load such that said human force and said device force together lift the load.