Actuator control method and actuator control device

Patent metadata

Field	Value
Publication number	US-9606517-B2
Application number	US-201214241366-A
Country	US
Kind code	B2
Filing date	Aug 10, 2012
Priority date	Aug 29, 2011
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

An actuator control method and an actuator control device that perform energy evaluation control that compares kinetic energy of a controlled object and work that can be done by braking and switches driving to braking at a point of time at which the kinetic energy of the controlled object and the work become equal, and also repeatedly makes a comparison between the kinetic energy of the controlled object and the work at each preset time, as a new control method that replaces PID control in mechanics for effectively utilizing vehicle energy to improve vehicle fuel consumption and control methods thereof, a control result is obtained by a simpler method.

First claim

The invention claimed is:

1. An actuator control method of accelerating and decelerating a controlled object to reach a target position by controlling an output of a control force of an actuator, comprising:
comparing a kinetic energy of the controlled object with an amount of a work that can be done by braking, which work is defined as the amount of work done by braking the controlled object in motion in a deceleration state until the controlled object reaches the target position from a present position, by a comparison unit of an actuator control device,
switching from driving to braking when the kinetic energy of the controlled object and the amount of the work that can be done by braking become equal, by a switching unit of the actuator control device;
repeatedly comparing the kinetic energy of the controlled object with the amount of the work that can be done by braking at each preset time, by the actuator control device;
taking a sum of the kinetic energy of the controlled object and an absolute value of the amount of the work that can be done by braking, and setting the sum to a control evaluation value for ending control, by the actuator control device; and
reducing an upper limit value of a control output in proportion to the control evaluation value, by the actuator control device.

2. The actuator control method according to claim 1 , further comprising:
ending the control when the control evaluation value is zero.

3. The actuator control method according to claim 2 , further comprising:
correcting the kinetic energy to “(kinetic energy)−(kinetic energy at target velocity)”, when the controlled object has a target velocity at a target position.

4. The actuator control method according to claim 2 , wherein, if a target value is taken to be Tr , a controlled value to be X, a mass to be m, and the kinetic energy is defined by “V=(½)×m×(dX/dt) 2 ” and the amount of the work that can be done by braking by “W=m×αb×(Tr−X)”, in a case where a deviation (Tr−X) between the target value Tr and the controlled value X is positive, an acceleration (αa) is set based on a maximum acceleration (αp) and a deceleration (αb) based on a maximum deceleration (αm) and, in a case where the deviation (Tr−X) is negative, the acceleration (αa) is set based on the maximum deceleration (αm) and the deceleration (αb) based on the maximum acceleration (αp), and further, in a case where the kinetic energy is smaller than the absolute value of the amount of the work that can be done by braking, output acceleration is set to the acceleration (αa) and, in a case where the kinetic energy is larger than the absolute value of the amount of the work that can be done by braking, the output acceleration is set to the deceleration (αb).

5. The actuator control method according to claim 2 , wherein, if a target value is taken to be Tr, a controlled value to be X, a mass to be m, a calculation period to be Δt, a present controlled value to be X 0 , a controlled value before one calculation period to be X −1 , and a controlled value before two calculation periods to be X −2 , and the kinetic energy is defined by “V=(½)×m×[(X 0 −X −1 )/Δt] 2 ” and the amount of the work that can be done by braking by “W=m×αb×(Tr−X)”, in a case where a deviation (Tr−X) between the target value Tr and the controlled value X is positive, an acceleration (αa) is set based on a maximum acceleration (αp) and a deceleration (αb) based on a maximum deceleration (αm) and, in a case where the deviation (Tr−X) is negative, the acceleration (αa) is set based on the maximum deceleration (αm) and the deceleration (αb) based on the maximum acceleration (αp), and further, in a case where the kinetic energy is smaller than the absolute value of the amount of the work that can be done by braking, output acceleration is set to the acceleration (αa) and, in a case where the kinetic energy is larger than the absolute value of the amount of the work that can be done by braking, the output acceleration is set to the deceleration (αb).

6. The actuator control method according to claim 1 further comprising:
correcting the kinetic energy to “(kinetic energy)−(kinetic energy at target velocity)”, when the controlled object has a target velocity at a target position.

7. The actuator control method according to claim 6 , wherein, if a target value is taken to be Tr, a controlled value to be X, a mass to be m, and the kinetic energy is defined by “V=(½)×m×(dX/dt) 2 ” and the amount of the work that can be done by braking by “W=m×αb×(Tr−X)”, in a case where a deviation (Tr−X) between the target value Tr and the controlled value X is positive, an acceleration (αa) is set based on a maximum acceleration (αp) and a deceleration (αb) based on a maximum deceleration (αm) and, in a case where the deviation (Tr−X) is negative, the acceleration (αa) is set based on the maximum deceleration (αm) and the deceleration (αb) based on the maximum acceleration (αp), and further, in a case where the kinetic energy is smaller than the absolute value of the amount of the work that can be done by braking, output acceleration is set to the acceleration (αa) and, in a case where the kinetic energy is larger than the absolute value of the amount of the work that can be done by braking, the output acceleration is set to the deceleration (αb).

8. The actuator control method according to claim 6 , wherein, if a target value is taken to be Tr, a controlled value to be X, a mass to be m, a calculation period to be Δt, a present controlled value to be X 0 , a controlled value before one calculation period to be X −1 , and a controlled value before two calculation periods to be X −2 , and the kinetic energy is defined by “V=(½)×m×[(X 0 −X −1 )/Δt] 2 ” and the amount of the work that can be done by braking by “W=m×αb×(Tr−X)”, in a case where a deviation (Tr−X) between the target value Tr and the controlled value X is positive, an acceleration (αa) is set based on a maximum acceleration (αp) and a deceleration (αb) based on a maximum deceleration (αm) and, in a case where the deviation (Tr−X) is negative, the acceleration (αa) is set based on the maximum deceleration (αm) and the deceleration (αb) based on the maximum acceleration (αp), and further, in a case where the kinetic energy is smaller than the absolute value of the amount of the work that can be done by braking, output acceleration is set to the acceleration (αa) and, in a case where the kinetic energy is larger than the absolute value of the amount of the work that can be done by braking, the output acceleration is set to the deceleration (αb).

9. The actuator control method according to claim 1 , wherein, if a target value is taken to be Tr, a controlled value to be X, a mass to be m, and the kinetic energy is defined by “V=(½)×m×(dX/dt) 2 ” and the amount of the work that can be done by braking by “W=m×αb×(Tr−X)”, in a case where a deviation (Tr−X) between the target value Tr and the controlled value X is positive, an acceleration (αa) is set based on a maximum acceleration (αp) and a deceleration (αb) based on a maximum deceleration (αm) and, in a case where the deviation (Tr−X) is negative, the acceleration (αa) is set based on the maximum deceleration (αm) and the deceleration (αb) based on the maximum acceleration (αp), and further, in a case where the kinetic energy is smaller than the absolute value of the amount of the work that can be done by braking, output acceleration is set to the acceleration (αa) and, in a case where the kinetic energy is larger than the absolute value of the amount of the work that can be done by braking, the output acceleration is set to the deceleration (αb).

10. The actuator control method according to claim 1 , wherein, if a target value is ta

Assignees

• Yamamoto Yasushi
• Isuzu Motors Ltd

Inventors

• Yamamoto Yasushi

Classifications

• G05B2219/43064

  Brake, decelerate at least one axis at maximum · CPC title

• G05B19/416 Primary

  characterised by control of velocity, acceleration or deceleration (G05B19/19 takes precedence) · CPC title

• G05B2219/43045

  Max torque, acceleration, then variable, then reverse, variable then max deceleration · CPC title

• G05B2219/34311

  Energy saving by recuperating braking, deceleration energy · CPC title

• G05B19/29

  for point-to-point control · CPC title