Apparatus and method to control the precisional position of a light weight motor energized by radiant energy

• US 4,926,037 A
• Filed: 11/23/1988
• Issued: 05/15/1990
• Est. Priority Date: 11/23/1988
• Status: Expired due to Fees

• Current Assignee: Martin-Lopez, Fernando R.
• Original Assignee: Martin-Lopez, Fernando R.
• Inventors: Martin-Lopez, Fernando R.
• Primary Examiner(s): Nelms, David C.
• Application Number:
  US07/276,105
• Time in Patent Office: 538 Days
• Field of Search: 356/216, 250/205, 250/216, 250/239, 250/231 SE
• US Class Current: 250/205
• CPC Class Codes: F03G 7/005 Electro-chemical actuators; Actuators having a material for absorbing or desorbing gas, e.g. a metal hydride; Actuators using the difference in osmotic pressure between fluids; Actuators with elements stretchable when contacted with liquid rich in ions, with UV light, with a salt solution
• CPC Class Codes: G01P 13/045 with speed indication
• CPC Class Codes: H02N 11/006 Motors

Abstract

A motor position controller energized by radiant energy, includes a member that rotates in response to radiant energy. A sensing means is mounted adjacent the absorbing member to sense rotational movement of the member and to generate a member rotational speed and direction movement signal in response thereto. A processor compares input command signals representing the desired member speed and rotational direction signal with the actual speed and rotational direction signal and generates a radiant energy control signal in response thereto. A radiant energy generating laser, controlled by the processor, transmits radiant light energy of varying magnitude onto the member thereby controlling the member'"'"'s rotational speed, direction and position. In a preferred embodiment, the member is mechanically engaged to a mechanical joint and is used to control the arm'"'"'s speed, position and movement.

Claims

1. In a motor energized by radiant energy, an apparatus to control motor drive rotation, comprising:

a drive member adapted to rotate in response to radiant energy,

a radiant energy emitting member adapted to emit radiant energy to said drive member,

a sensor means mounted adjacent said drive member and adapted to sense rotational movement of said drive member and to generate a member rotational speed and direction signal,

processor for comparing an input command signal representing desired speed and rotational direction of said motor drive shaft with said member rotational speed and direction signal and to generate a radiant energy control signal in response thereto, and

radiant energy distributing means, electrically connected to said processor means for receiving said radiant energy control signal, and responsive to said control signal to cause said radiant energy emitting member to vary the emission level of said radiant energy in response thereto.

2. The apparatus of claim 1, further comprising a motor drive mechanically engaged to said drive member and adapted to rotate in response to said drive member rotations, and a mechanical joint mechanically engaged to said motor drive and adapted to move a predefined distance in response to rotational movement of said motor drive.

3. The apparatus of claim 2, wherein said mechanical joint moves a predefined forward distance in response to clock wise rotations of said member, and a predefined reverse distance in response to counter clock wise rotations of said member.

4. The apparatus of claim 1, wherein said sensor means comprise a photocell adapted to generate a rotational speed sine wave output in response to the rotational speed of said drive member, and positive polarity in response to clockwise rotations of said member, or a negative polarity in response to counter clock wise rotations of said member.

5. The apparatus of claim 4, wherein said sensor further comprises a transducer electrically connected to receive direction signal sine wave output and said positive or negative polarity signal, and to generate an output square wave pulse corresponding to each peak of said sine wave and of a polarity corresponding to said polarity signal to be provided to said processor.

6. The apparatus of claim 5, wherein said processor is a processor electrically connected to receive and compare said input command signal and said transducer output square wave pulse, and adapted to generate said radiant energy control signal further characterized by a square wave train with a frequency corresponding to desired member rotational frequency and polarity corresponding to member rotational direction.

7. The apparatus of claim 6, further comprising a light transducer electrically connected to said processor and for receiving said radiant energy control signal and converting said radiant energy control signal into an analog signal characterized by magnitude and polarity whereby said analog signal is provided to said radiant energy distributing means.

8. The apparatus of claim 7, wherein said radiant energy means comprises an integrated laser chip electrically connected to receive said analog signal characterized by magnitude and polarity and adapted to generate light radiant energy with an intensity proportional to the magnitude of said analog signal and directing said radiant energy onto said drive member.

9. The apparatus of claim 8, said drive member comprising a first rotor adapted to rotate in a clock wise direction to effectuate clock wise rotations of said motor drive, and a second rotor, located below said first rotor, adapted to rotate in a counter clock wise direction to effectuate counter clock wise rotations of said motor drive.

10. The apparatus of claim 9, wherein said first rotor comprising a first plurality of flat energy absorbing/emitting surfaces extending outward about said first rotor periphery, and said second rotor comprising a second plurality of flat energy absorbing/emitting surfaces extending outward about said second rotor periphery.

11. The apparatus of claim 10, wherein said first plurality of flat energy absorbing/emitting surfaces each comprise two sides, a first side blackened with an energy absorbing layer of sulfide, and a second side lightened with an energy emitting layer of magnesium carbonate, said blackened sides of each said surface all facing the same direction.

12. The apparatus of claim 11, wherein said second plurality of flat energy absorbing/emitting surfaces comprise two sides, a first side lightened with an energy emitting layer of magnesium carbonate, and a second side darkened with an energy absorbing layer of sulfate, and said blackened sides of each said surface facing the same direction.

13. The apparatus of claim 12, wherein said blackened sides of said first energy absorbing/emitting surfaces face the opposite direction of said blackened sides of said second energy absorbing/emitting surfaces.

14. The apparatus of claim 9, wherein said radiant energy emitting means further comprises a first radiant energy emitting array, optically connected to said integrated laser chip by a first fiber optic, said first radiant energy emitting array comprising a plurality of optic emitting diodes arranged to direct light radiant energy onto said first rotor surfaces, a second radiant energy emitting array, optically connected to said integrated laser chip by a second fiber optic, said second radiant energy emitting array comprising a plurality of optic emitting diodes arranged to direct light radiation energy onto said second rotor surfaces to effectuate said rotor rotations.

15. The apparatus of claim 14, further comprising a switch located on said integrated laser chip and adapted to switch radiant energy to said first fiber optic to effectuate clock wise rotation of said first rotor responsive to said light transducer analog signal of positive polarity, or to switch radiant energy to said second fiber optic to effectuate counter clock wise rotation of said second rotor when said light transducer analog signal is of negative polarity.

16. The apparatus of claim 15 wherein clockwise rotations of said first rotor prevents counter clockwise rotations of said second rotor, and counter clockwise rotations of said second rotor prevents clockwise rotations of said first rotor.

17. The apparatus of claim 16, further comprising a light shield mechanically arranged between said first rotor and said second rotor adapted to shield radiant energy emitted from said first energy emitting array from falling onto said second rotor, and to shield radiant energy emitted from said second energy emitting array from falling onto said first rotor.

18. The apparatus of claim 7, wherein said rotating member comprises a single rotor adapted to rotate in a clock wise or a counter clock wise rotation to effectuate clock wise or counter clock wise rotations of said motor drive.

19. The apparatus of claim 18, wherein said rotor comprises a plurality of surfaces extending outward about said rotor periphery, each surface comprising a first and a second side blackened with an energy absorbing layer of sulfide.

20. The apparatus of claim 19, further comprising a polarity sensitive electrical switch electrically connected between said light transducer and a said first radiant energy generator and a second radiant energy generator, said electrical switch directing said analog signal to first radiant energy generator when said analog signal is of positive polarity, and directing said analog signal to said second radiant energy generator when said analog signal is of negative polarity.

21. The apparatus of claim 20, wherein said first radiant energy generator comprises a first integrated laser chip electrically connected to receive said analog signal characterized by magnitude and polarity, and a second integrated laser chip, and a second radiant energy generator comprising a second integrated laser chip.

22. The apparatus of claim 21, wherein said first integrated laser chip is positioned to direct radiant energy onto said first side of said rotor surfaces to effectuate clock wise rotation of said rotor, and said second integrated laser chip is positioned to direct radiant energy onto said second side of said rotor surfaces to effectuate counter clock wise rotations.

23. The apparatus of claim 3, wherein said rotating member comprises a single rotor adapted to rotate in a clock wise or a counter clock wise rotation to effectuate clock wise or counter clock wise rotations of said motor drive.

24. The apparatus of claim 23, wherein said rotor comprises a plurality of surfaces extending outward about said rotor periphery, each surface comprising a first and a second side blackened with an energy absorbing layer of sulfide.

25. The apparatus of claim 24, wherein said radiant energy emitting member comprises a light emitting array of a plurality of photoemitting tracks arranged in a star pattern below said surfaces and adapted to emit radiant energy onto said surfaces, each said track spaced a preset number of degrees apart.

26. The apparatus of claim 25, wherein said sensor means further comprises a plurality of photosensors arranged circumferentially around said rotor, each designated a predetermined number of degrees apart, said photosensor outputs, together, adapted to generate a binary word, wherein said binary word sequences upward with clock wise rotations of said rotor, and sequences downward with counter clock wise rotations of said rotor.

27. The apparatus of claim 26, wherein said processor comprises a processor electrically connected to receive said binary word, and said input command signal representing desired rotor speed and rotational direction and to generate in response thereto said radiant energy control signal comprising an encoded binary word, said encoded binary word controlling said light array to effectuate forward precisional movement of said rotor, reverse precisional movement of said rotor, and precisional positioning of said rotor.

28. The apparatus of claim 1, wherein said member adapted to rotate and said motor drive comprise a light weight plastic material.

29. In a motor energized by radiant energy, a method to control motor drive rotation, comprising the steps of:

rotating a member in response to radiant energy,

mechanically engaging to said member a motor drive shaft adapted to rotate in response to said radiant member rotations;

sensing rotational movement of said member rotational speed and direction signal in response thereto,

comparing an input command signal representing desired speed and rotational direction of said motor drive shaft with said member rotational speed and direction signal and generating a radiant energy control signal in response thereto, and

generating variations of radiant energy responsive to said radiant energy control signal, and

transmitting said variations of radiant energy to said member thereby effectuating controlled rotation of said member.