Moving object controller containing a differential of acceleration measurer

• US 5,960,376 A
• Filed: 07/01/1997
• Issued: 09/28/1999
• Est. Priority Date: 02/17/1992
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamakado, Makoto, Kadomukai, Yuzo
• Primary Examiner(s): ASSOUAD, PATRICK J
• Application Number:
  US08/886,412
• Time in Patent Office: 819 Days
• Field of Search: 702/141, 324/162, 73/488, 73/514.36, 701/37, 701/70, 701/79, 303/177, 303/181, 303/182, 318/276, 364/174, 364/474.3
• US Class Current: 702/141
• CPC Class Codes: B60G 17/01908 Acceleration or inclination sensors characterised by the use of gyroscopes B60G21/08
• CPC Class Codes: B60G 2400/10 Acceleration; Deceleration
• CPC Class Codes: B60G 2400/102 vertical
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/20 Speed
• CPC Class Codes: B60G 2400/25 Stroke; Height; Displacement
• CPC Class Codes: B60G 2600/14 Differentiating means, i.e. differential control
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/014 Pitch; Nose dive
• CPC Class Codes: B60G 2800/22 Braking, stopping
• CPC Class Codes: B60G 2800/24 Steering, cornering
• CPC Class Codes: B60G 2800/914 Height Control System
• CPC Class Codes: B60G 2800/92 ABS - Brake Control
• CPC Class Codes: B60G 2800/96 ASC - Assisted or power Steering control
• CPC Class Codes: E04H 9/02 withstanding earthquake or sinking of ground foundations E02D27/34
• CPC Class Codes: G01P 15/001 by measuring acceleration changes by making use of a triple differentiation of a displacement signal
• CPC Class Codes: G01P 15/11 by inductive pick-up
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 15/131 with electrostatic counterbalancing means
• CPC Class Codes: G01P 15/132 : with electromagnetic counterbalancing means
• CPC Class Codes: G01P 15/18 : in two or more dimensions
• CPC Class Codes: G01P 2015/0828 : the mass being of the paddle type being suspended at one of its longitudinal ends

Abstract

In order to control a movable object such as an automobile, the differential of acceleration is derived and used as control information. In order to derive that differential, a value representing the acceleration may be differentiated, but preferably a sensor is provided which generates a direct measurement of the differential of acceleration. In one example of such a sensor, a pendulum has a coil thereon which interacts with the magnetic field of a magnet on a casing supporting the pendulum. A current is supplied to the coil such as to generate a force resisting movement of the pendulum. It is then found that the voltage across the coil corresponds to the differential of acceleration.

Claims

1. A controller having a closed central loop for controlling acceleration or force of a movable object, comprising:

a sensor for directly measuring a value representing a differential of acceleration of said movable object; and

means for generating a control signal in dependence on said value, including means for feeding back in said closed central loop a value derived by multiplying a measured value of a differential of acceleration by a gain, thereby to control said movable object.

2. A controller according to claim 1, wherein said sensor operates to produce said value directly from said movement of said object.

3. A controller according to claim 1, wherein said sensor operates to measure both an amount of acceleration corresponding to movement of said body and said value of differential of acceleration.

4. A controller according to claim 1, wherein said sensor comprises:

electromagnetic force generating means having a coil and a magnet;

a movable member driven by said electromagnetic force generating means;

displacement detecting means for detecting the displacement of said movable member;

current supply means for supplying current to said coil of said electromagnetic force generating means on the basis of output of said displacement detection means so that said movable member is positioned at a reference position; and

voltage detecting means for detecting the voltage of said coil produced by said current to position the movable member at said reference position, wherein said voltage directly corresponds to the differential of acceleration.

5. A controller according to claim 4, wherein said displacement detecting means for detecting displacement of said movable member relative to a first member includes capacitor plates mounted on said first member and said movable member, respectively, and sensing means for sensing the variation of capacitance of said capacitor plates due to displacement of said movable member relative to said first member.

6. A controller according to claim 5, wherein said movable member is a pendulum.

7. A controller according to claim 5, wherein said first member is a casing of said sensor.

8. A controller according to claim 5, wherein said movable member is mounted so as to be rotatable relative to said first member, whereby said voltage corresponds to a value of differential rotational acceleration.

9. A controller having a closed control loop for controlling acceleration or force of a movable object, comprising:

a sensor for directly measuring a first value representing an acceleration of said movable object and a second value representing a differential of acceleration of said movable object; and

means for generating a control signal in dependence on said first value and said second value, including means for feeding back in said closed control loop a value derived by multiplying a measured first value of acceleration by a gain and a value derived by multiplying a measured second value of a differential of acceleration by a gain, thereby to control said movable object.

10. A method of controlling acceleration or force of a moving object using a feedback control system including a closed control loop, comprising the steps of:

detecting movement of said moving object;

measuring a value directly representing a differential of acceleration corresponding to said movement by using a sensor for measuring differential of acceleration; and

generating a control signal in dependence on said value, through derivation of a feedback value by multiplying the measured value of differential acceleration by a gain, and through feedback of said feedback value in said closed control loop, thereby to control said moving object.

11. The combination of:

a movable object;

means for generating a force in a predetermined direction on said movable object; and

a control system having a differential acceleration feedback control loop for generating a control signal for controlling said means for generating said force;

said control system comprising;

a sensor for directly measuring a value representing a differential of acceleration of said movable object; and

means for generating said control signal in dependence on said value representing a differential of acceleration, including means for feeding back in said feedback control loop a value derived by multiplying said value of differential of acceleration by a gain.

12. The combination according to claim 11, wherein said movable object is an automobile.

13. The combination according to claim 12 wherein said means for generating a force is a steering apparatus for steering said automobile and said predetermined direction is transverse to said automobile.

14. The combination according to claim 12, wherein said means for generating said force is a braking system for braking movement of said automobile, and said predetermined direction is longitudinal to said automobile.

15. The combination according to claim 12, wherein said means for generating said force is a motor for said automobile, and said predetermined direction is longitudinal to said automobile.

16. The combination according to claim 12, wherein said means for generating said force is a suspension for said automobile, and said predetermined direction is vertical.

17. The combination according to claim 11, wherein said movable object is an engine of an automobile, and said means for generating said force is a suspension for said engine.

18. The combination according to claim 11, wherein said movable object is a elevator cage, and said means for generating said force is a drive system for said elevator cage.

19. The combination according to claim 11, wherein said movable object is an earthquake simulator table and said means for generating said force comprises actuators for said earthquake simulator table.

20. The combination according to claim 11, wherein said movable object is an XY stage and said means for generating said force comprise actuators for said XY stage.

21. The combination according to claim 11, wherein said movable object is a building and said means for generating said force is a movable damper.

22. The combination according to claim 11, wherein said movable object is a railway vehicle, and said means for generating said force comprise actuators of a suspension of said railway vehicle.

23. The combination according to claim 11, wherein said movable object is a magnetic levitation vehicle and said means for generating said force comprising magnets acting on said magnetic levitation vehicle.

24. The combination according to claim 11, wherein said movable object is a manipulator.

25. The combination according to claim 11 wherein said movable object is an airplane.

26. The combination according to claim 11, wherein said sensor comprises:

electromagnetic force generating means having a coil and a magnet;

a movable member driven by said electromagnetic force generating means;

displacement detecting means for detecting the displacement of said movable member;

current supply means for supplying current to said coil of said electromagnetic force generating means on the basis of output of said displacement detection means so that said movable member is positioned at a reference position; and

voltage detecting means for detecting the voltage of said coil produced by said current to position the movable member at said reference position, wherein said voltage directly corresponds to the differential of acceleration.

27. The combination according to claim 26, wherein said sensor is fixed to said movable object.

28. A control system for controlling acceleration of a movable body, comprising:

means for directly detecting a differential of acceleration from movement of said movable body;

a closed control loop having a feedback path and means for supplying to said feedback path a value derived by multiplying a value of differential of acceleration from said detecting means by a gain; and

means responsive to said closed control loop for controlling the acceleration of said movable body.

29. A control system according to claim 28, wherein said detecting means is a sensor comprising:

electromagnetic force generating means having a coil and a magnet;

a movable member driven by said electromagnetic force generating means;

displacement detecting means for detecting the displacement of said movable member;

current supply means for supplying current to said coil of said electromagnetic force generating means on the basis of output of said displacement detection means so that said movable member is positioned at a reference position; and

voltage detecting means for detecting the voltage of said coil produced by said current to position the movable member at said reference position, wherein said voltage directly corresponds to the differential of acceleration.

30. A control system for controlling a force on a movable body, comprising:

means for directly detecting a differential of acceleration from movement of said movable body;

a closed control loop having a feedback path and means for supplying to said feedback path a value derived by multiplying a value of differential of acceleration from said detecting means by a gain; and

means responsive to said closed control loop for controlling a force on said movable body.

31. A control system according to claim 30, wherein said detecting means is a sensor comprising:

electromagnetic force generating means having a coil and a magnet;

a movable member driven by said electromagnetic force generating means;

displacement detecting means for detecting the displacement of said movable member;

current supply means for supplying current to said coil of said electromagnetic force generating means on the basis of output of said displacement detection means so that said movable member is positioned at a reference position; and

voltage detecting means for detecting the voltage of said coil produced by said current to position the movable member at said reference position, wherein said voltage directly corresponds to the differential of acceleration.

32. A control system for controlling a movable object, comprising:

a sensor for directly measuring a first value representing an acceleration of said movable object and a second value representing a differential of acceleration of said movable object;

means for generating a movement comfort evaluation factor using both said first value and said second value; and

means for controlling movement of said object using said movement comfort evaluation factor.

33. A control system according to claim 32, wherein said sensor comprises:

electromagnetic force generating means having a coil and a magnet;

a movable member driven by said electromagnetic force generating means;

displacement detecting means for detecting the displacement of said movable member;

current supply means for supplying current to said coil of said electromagnetic force generating means on the basis of output of said displacement detection means so that said movable member is positioned at a reference position; and

voltage detecting means for detecting the voltage of said coil produced by said current to position the movable member at said reference position, wherein said voltage directly corresponds to the differential of acceleration.

34. A control system according to claim 32, wherein said movable object is an automobile engine, and said movement controlling means is means for controlling a suspension for said engine.

35. A control system according to claim 32, wherein said movable object is an elevator cage, and said movement controlling means is a drive system for said elevator cage.

36. A control system according to claim 32, wherein said movable object is a vibration stage, and said movement controlling means comprises means for controlling actuators for said vibration stage.