Motion base with controlled actuators

Patent metadata

Field	Value
Publication number	US-9415507-B2
Application number	US-201414566271-A
Country	US
Kind code	B2
Filing date	Dec 10, 2014
Priority date	Dec 10, 2013
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

A motion base comprises lower and upper plates, a plurality of lateral stabilizers coupled in-between and connected to the lower and upper plates, a plurality of actuators, and one or more associated active controllers. Actuators typically comprise a body operatively connected to the upper plate and the lower plate, a rod movably disposed at least partially within the body, where the rod and body define an actuator effective length; and a controllable rod extender configured to selectively extend the rod out from and retract the rod into the body. After determining a desired parameter such as length and an actual parameter such as length, velocity, acceleration, impulse, force, or the like, or a combination thereof for each of the plurality of actuators, a control signal is sent to each controllable rod extender as needed to change the current effective state of that parameter of each actuator by moving each such actuator's extendable rod into or out from each such actuator's body such that the current parameter for each of the plurality of actuators matches the desired parameter for that actuator.

First claim

What is claimed is:

1. A motion base, comprising:
a. a lower plate;
b. an upper plate;
c. a plurality of lateral stabilizers disposed in-between and connected to the lower and upper plates, the plurality of lateral stabilizers configured to provide lateral and torsional stability between the lower and upper plates;
d. a plurality of actuators, each actuator operatively connected to the upper plate and the lower plate, each actuator comprising:
i. a body;
ii. a rod movably disposed at least partially within the body, the rod comprising a proximal end disposed within the body and a distal end extending out from the body, the distal end operatively connected to an opposing one of the upper plate or the lower plate, the rod and body defining an actuator effective length; and
iii. a controllable rod extender operatively coupled to the proximal end of the rod and configured to selectively extend the rod out from and retract the rod into the body, effectively causing the actuator to dynamically change its effective length from a first predetermined length to a second predetermined length; and

e. an active controller operatively in communication with the controllable rod extender and configured to selectively effect the extension of the rod out from and retraction of the rod into the body.

2. The motion base of claim 1 , wherein the controllable rod extender comprises a controllable rod extender.

3. The motion base of claim 1 , wherein the controllable rod extender driver comprises an electric motor, an electrically controlled linear motor, a hydraulic piston, or a pneumatic piston.

4. The motion base of claim 1 , further comprising a movable joint disposed between one of the bodies and the distal end of the rod that body.

5. The motion base of claim 1 , wherein:
a. the active controller further comprises an active feedback control loop; and
b. the controllable rod extender comprises a controllable rod extender driver, operatively in communication with the active feedback control loop.

6. The motion base of claim 5 , wherein:
a. the active controller further comprises a sensor operatively in communication with the active feedback control loop; and
b. the active feedback control loop comprises at least one of a positional feedback control loop, a velocity feedback control loop, an acceleration feedback control loop, an impulse feedback control loop, or a force compliance feedback control loop.

7. The motion base of claim 1 , wherein the controllable rod extender comprises a linear Acme screw type actuator, a linear ball screw type actuator, or a linear roller screw type actuator.

8. The motion base of claim 1 , wherein the distal end of the rod is disposed adjacent to a vertex of an imaginary triangle projected onto one of the upper and lower plates.

9. The motion base of claim 1 , wherein each the rod extension out from and retraction into the body is configured to be continuously variable.

10. The motion base of claim 1 , wherein the rod extension out from and retraction into the body is configured to be stepwise variable.

11. The motion base of claim 1 , wherein the body and the distal end of the rod are coupled to respective ones of the upper and lower plates via joints configured to allow two rotational degrees of freedom.

12. The motion base of claim 11 , wherein the allowed two rotational degrees of freedom do not include heave.

13. The motion base of claim 1 , wherein when the rod is configured to prevent the distance between the upper plate and lower plate from oscillating when the rod is moved to stop at a predetermined length.

14. The motion base of claim 1 , wherein the actuator is coupled to the upper plate and the lower plate via a U-joint.

15. A method of effecting a change in a relationship between an upper plate of a motion base and a lower plate of a motion base, comprising:
a. providing a motion base, the motion base comprising:
i. a lower plate;
ii. an upper plate;
iii. a plurality of lateral stabilizers disposed in-between and connected to the lower and upper plates, the plurality of lateral stabilizers configured to provide lateral and torsional stability between the lower and upper plates;
iv. a plurality of actuators, each actuator operatively connected to the upper plate and the lower plate, each actuator comprising:
1. a body;
2. a rod movably disposed at least partially within the body, the rod comprising a proximal end disposed within the body and a distal end extending out from the body, the distal end operatively connected to an opposing one of the upper plate or the lower plate, the rod and body defining an actuator effective length; and
3. a controllable rod extender operatively coupled to the proximal end of the rod and configured to selectively extend the rod out from and retract the rod into the body, effectively causing the actuator to dynamically change its effective length from a first predetermined length to a second predetermined length; and

v. an active controller operatively in communication with the controllable rod extender and configured to selectively effect the extension of the rod out from and retraction of the rod into the body;

b. determining a desired effective state of a parameter for each of the plurality of actuators;
c. determining a current effective state of the parameter for each of the plurality of actuators; and
d. sending a control signal to each controllable rod extender of each actuator to change the current effective state of the parameter of each actuator if needed to match the current effective state of the parameter to the desired effective length by moving each such actuator's extendable rod into each such actuator's body or moving each such actuator's extendable rod out from each such actuator's body such that the current effective length for each of the plurality of actuators matches the desired parameter for that actuator.

16. The method of effecting a change in a relationship between an upper plate of a motion base and a lower plate of a motion base of claim 15 , further comprising:
a. outputting a signal indicative of present effective parameter of an actuator from a sensor operatively coupled to the actuator, the sensor configured to determine a current state of the parameter;
b. receiving the output indicative signal as a first input signal at a comparator circuit;
c. using the comparator circuit to compare the first input signal to a second input signal received from the active controller operatively in communication with the comparator circuit and a processor to create a compared signal;
d. providing the compared signal to a servo amplifier operatively in communication with comparator and the controllable rod extender; and
e. using the compared signal to create a control signal that effects a change in the current effective state of the parameter of each actuator as needed, the control signal operative to move an actuator's extendable rod into the actuator's body or move the actuator's extendable rod out from the actuator's body such that the current effective state parameter for the actuator matches the desired effective state parameter for that actuator.

17. The method of effecting a change in a relationship between an upper plate of a motion base and a lower plate of a motion base of claim 15 , wherein the controllable rod extender comprises an electric controllable rod extender, the electric controllable rod extender comprising an electric linear motor, the method further comprising using the electric linear motor to effectively lock the electric controllable rod extende

Assignees

• Oceaneering Int Inc

Inventors

• Foster Samuel T
• King Eric A
• Fromyer Stephen F
• Sywak Stephen

Classifications

• G05B11/011

  details of the correcting means · CPC title

• A63G31/06

  with undulatory motion of the substructure · CPC title

• F16H25/20

  Screw mechanisms (with automatic reversal F16H25/12) · CPC title

• B25J9/123 Primary

  Linear actuators · CPC title

• G09B9/12 Primary

  Motion systems for aircraft simulators · CPC title