POWERED SEAT AND CONTROL THEREOF

• US 20150375865A1
• Filed: 06/26/2014
• Published: 12/31/2015
• Est. Priority Date: 06/26/2014
• Status: Active Grant

• Current Assignee: ITT Manufacturing Enterprises LLC (ITT, Inc.)
• Original Assignee: ITT Manufacturing Enterprises LLC (ITT, Inc.)
• Inventors: Fischer, Brian, McIntyre, Stephen, Matusek, Robert D.
• Granted Patent: US 9,481,466 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60N 2/02 the seat or part thereof being movable, e.g. adjustable adjustable arm-rests B60N2/75; adjustable head-rests B60N2/806
• CPC Class Codes: B60N 2/02246 Electric motors therefor
• CPC Class Codes: B60N 2/0244 with logic circuits
• CPC Class Codes: B60N 2/0268 using sensors or detectors for adapting the seat or seat part, e.g. to the position of an occupant
• CPC Class Codes: B60N 2/0272 using sensors or detectors for detecting the position of seat parts
• CPC Class Codes: B60N 2/06 slidable B60N2/12 , B60N2/2209 take precedence
• CPC Class Codes: B60N 2/16 height-adjustable
• CPC Class Codes: B60N 2/22 the back-rest being adjustable B60N2/2878 takes precedence
• CPC Class Codes: B60N 2/62 Thigh-rests B60N2/914 takes precedence
• CPC Class Codes: B60N 2/66 Lumbar supports
• CPC Class Codes: B60N 2/665 using inflatable bladders
• CPC Class Codes: B60N 2/77 Height adjustment
• CPC Class Codes: B60N 2/809 vertically slidable
• CPC Class Codes: B60N 2/919 Positioning and locking mechanisms B60N2/16, B60N2/18, B60N2/22, B60N2/225 take precedence
• CPC Class Codes: B60N 2/929 linear
• CPC Class Codes: B60N 2/933 rotatable
• CPC Class Codes: B60N 2/986 Side-rests B60N2/2872, B60N2/885 take precedence
• CPC Class Codes: B60N 2/995 Lower-leg-rests, e.g. calf-rests
• CPC Class Codes: B60N 2002/924 using electric or hydraulic energy
• CPC Class Codes: B60N 2210/14 Inductive; Magnetic field
• CPC Class Codes: B60N 2230/10 : Wired data transmission
• CPC Class Codes: B64D 11/0639 : with features for adjustment or converting of seats
• CPC Class Codes: B64D 11/064 : Adjustable inclination or position of seats

Abstract

A method of controlling motion of movable components of a powered seat includes, using the controller, monitoring a feedback signal of an actuator during motion of a component. During an acceleration phase of the motion of the component, a reference state of the time-varying motion command is detected and a reference value of the monitored feedback signal is determined as a reference value. A feedback-signal acceptance range is determined using the reference value of the monitored feedback signal. During a steady-state phase of the motion, the motion of the component is terminated if the monitored feedback signal departs the determined feedback-signal acceptance range. A control system for a powered seat of a vehicle is described. A powered seat assembly is described.

Claims

1. A method of controlling the motion of movable components of a powered seat, the powered seat including a controller responsive to a time-varying motion command and at least one actuator for moving the components over a range of positions, the method comprising:

using the controller, monitoring a feedback signal of the at least one actuator during the motion of at least one component;

during an acceleration phase of the motion of the component, automatically detecting a reference state of the time-varying motion command;

determining a reference value of the monitored feedback signal corresponding to the reference state of the time-varying motion command using the controller;

automatically determining a feedback-signal acceptance range using the reference value of the monitored feedback signal; and

during a steady-state phase of the motion, automatically terminating the motion of the at least one component if the monitored feedback signal departs the determined feedback-signal acceptance range.

2. The method according to claim 1, wherein the feedback signal includes a drive current of the actuator.

3. The method according to claim 2, wherein the at least one actuator is configured to provide a motion-status signal, the method further comprising receiving an indication of the motion and automatically providing the time-varying motion command in response to the received command and the motion-status signal.

4. The method according to claim 1, further including, after terminating the motion, a retrograde step of automatically driving the actuator in a direction that is opposite a direction of the motion.

5. The method according to claim 4, wherein the retrograde step includes driving the actuator a selected distance in the direction that is opposite the direction of motion.

6. The method according to claim 1, wherein the time-varying motion command includes a sequence of velocity command values and the controller detects the reference state when the sequence of velocity command values exhibits a selected slope value.

7. The method according to claim 1, wherein the time-varying motion command includes a sequence of velocity command values and the controller detects the reference state when the sequence of velocity command values exhibits a peak slope value.

8. The method according to claim 7, wherein said detecting the reference state includes determining a sequence of velocity slope values using the sequence of velocity command values and detecting a peak slope value in the sequence of velocity slope values, and said determining the reference value includes determining a value of the feedback signal a selected time after the peak slope value is detected.

9. The method according to claim 1, wherein the motion command includes a sequence of velocity command values and the controller automatically transitions between the acceleration phase and the steady-state phase when the sequence of velocity command values exhibits a slope value less than a selected steady-state slope threshold.

10. The method according to claim 1, wherein the feedback-signal acceptance range extends up to the higher of the reference value of the monitored feedback signal and a selected low-limit threshold.

11. The method according to claim 1, further including, during the steady-state phase of the motion, automatically updating the determined feedback-signal acceptance range based on the motion command.

12. The method according to claim 11, wherein the motion command includes a sequence of velocity command values and the updating of the determined feedback-signal acceptance range is performed when the sequence of velocity command values exhibits a slope having a magnitude greater than a selected velocity-slope-magnitude threshold.

13. The method according to claim 12, further including, during the steady-state phase, determining a runtime value of the feedback signal, wherein the updating of the determined feedback-signal acceptance range includes updating an upper limit of that range to the higher of the runtime value of the monitored feedback signal and a selected low-limit threshold.

14. The method according to claim 1, further including, during the steady-state phase of the motion, automatically updating the determined feedback-signal acceptance range based on the monitored feedback signal.

15. The method according to claim 14, wherein the monitored feedback signal includes a sequence of drive current values and the updating of the determined feedback-signal acceptance range is performed when the sequence of drive current values exhibits a slope having a magnitude less than a selected current-slope-magnitude threshold.

16. The method according to claim 15, wherein said monitoring the feedback signal includes determining a sequence of drive-current slope values using the sequence of drive current values and detecting an excursion in the sequence of velocity slope values beyond a selected steady-current range, and said updating of the determined feedback-signal acceptance range includes determining a value of the feedback signal a selected time after the excursion is detected and updating an upper limit of that range to the higher of the determined value of the feedback signal and a selected low-limit threshold.

17. The method according to claim 14, further including, during the steady-state phase, determining a runtime value of the feedback signal, wherein the updating of the determined feedback-signal acceptance range includes updating an upper limit of that range to the higher of the runtime value of the monitored feedback signal and a selected low-limit threshold.

18. The method according to claim 17, further including, during the steady-state phase of the motion, automatically updating the determined feedback-signal acceptance range based on the motion command.

19. The method according to claim 1, wherein the range of positions is divided into a plurality of zones having respective values of a parameter, and the step of determining the feedback-signal acceptance range includes automatically determining one of the zones in which the at least one component is located and determining the feedback-signal acceptance range using the respective parameter value of the determined one of the zones.

20. A powered seat assembly, comprising:

a) a back support;

b) a seat pan having a rearward portion associated with the back support;

c) a leg rest having a first end associated with a forward portion of the seat pan, each of said back support, said seat pan and said leg rest being movable;

d) one or more actuator(s) configured to move at least one of the back support, seat pan, and leg rest in response to one or more time-varying motion command(s), and to provide motion-status signal(s);

e) a driver configured to provide the motion command(s) in response to a time-varying motion command and the motion-status signal(s);

f) a sensor unit configured to monitor one or more time-varying feedback signal(s) of the actuator(s); and

g) a controller configured to determine respective feedback-signal acceptance range(s) for at least one of the actuator(s) using value(s) of the respective feedback signal(s) monitored during an acceleration phase of motion of the respective actuator(s), and to terminate motion of the respective actuator(s) if the respective feedback signal(s) depart the respective feedback-signal acceptance range(s) during a steady-state phase of motion of the respective actuator(s).

21. The assembly according to claim 20, wherein the controller is further configured to update at least one of the feedback-signal acceptance range(s) for at least one of the actuator(s) using value(s) of the respective feedback signal(s) monitored during the steady-state phase of motion of the respective actuator(s)

22. The assembly according to claim 20, wherein the feedback signal(s) include one or more current signal(s) of the actuator(s).

23. The assembly according to claim 20, wherein the motion command(s) include one or more commanded velocities of the one or more actuator(s).

24. The assembly according to claim 20, wherein each of the one or more actuator(s) includes a brushed direct-current (BDC) or brushless direct-current (BLDC) motor.

25. The assembly according to claim 20, wherein the one or more actuator(s) includes a respective actuator for each of the back support, the seat pan, and the leg rest, each of the respective actuators responsive to a respective one of the motion command(s) and configured to provide respective ones of the motion-status signal(s).

26. The assembly according to claim 20, further including a vertically-movable armrest, wherein at least one of the actuator(s) is configured to move the armrest in response to the one or more time-varying motion command(s) and provide corresponding one(s) of the motion-status signal(s).

27. The assembly according to claim 20, further including a privacy screen, wherein at least one of the actuator(s) is configured to raise or lower the privacy screen in response to the one or more time-varying motion command(s) and provide corresponding one(s) of the motion-status signal(s).

28. The assembly according to claim 20, further including a seat frame supporting the back support, the seat pan, and the leg rest, wherein at least one of the actuator(s) is configured to move the seat frame laterally in response to the one or more time-varying motion command(s) and provide corresponding one(s) of the motion-status signal(s).

29. The assembly according to claim 20, wherein the controller includes a nonvolatile memory configured to store parameter(s) of at least one zone of motion of at least one of the actuator(s) and a processor connected to the memory and configured to determine the respective feedback-signal acceptance range(s) using ones of the stored parameter(s) corresponding to the respective actuator(s).

30. The assembly according to claim 20, further including an interface for receiving an indication of a desired motion, wherein the controller is responsive to the received indication to provide the motion command(s).

31. The assembly according to claim 30, wherein the interface includes at least one element selected from the group consisting of a keypad, a pushbutton, a touchscreen, and a wireless interface.

32. The assembly according to claim 20, wherein at least one of the actuator(s) is configured to move a respective component over a range of positions divided into a plurality of zones having respective values of a parameter, and the controller is configured to determining the feedback-signal acceptance range by determining one of the zones in which the respective component is located and determining the feedback-signal acceptance range using the respective parameter value of the determined one of the zones.

33. A control system for a powered seat of a vehicle, the seat including at least one component that is movable over a range of positions and an actuator responsive to a time-varying motion command to move the at least one component, the control system including:

a) a receiver for receiving a feedback signal of the actuator;

b) a transmitter for transmitting the time-varying motion command to the actuator; and

c) a controller connected to the receiver and the transmitter and configured to determine a feedback-signal acceptance range using the feedback signal during an acceleration phase of the time-varying motion command, and to terminate motion if the feedback signal departs the determined feedback-signal acceptance range during a steady-state phase of the time-varying motion command.

34. The system according to claim 33, wherein the controller is configured to:

transmit an acceleration signal via the transmitter;

during transmission of the acceleration signal, monitor the feedback signal via the receiver and select a reference value of the feedback signal corresponding to a reference state of the motion command;

determine the feedback-signal acceptance range using the selected reference value of the feedback signal;

after transmission of the acceleration signal, transmit a steady-state motion signal via the transmitter; and

during transmission of the steady-state motion signal, monitor the feedback signal via the receiver and terminate the motion by automatically terminating transmission of the steady-state motion signal if the monitored feedback signal departs the determined feedback-signal acceptance range.

35. The system according to claim 34, further including an interface for receiving an indication of a desired motion, wherein the controller is responsive to the received indication to determine the feedback-signal acceptance range.

36. The system according to claim 33, further including an interface for receiving an indication of a desired motion, wherein the controller is responsive to the received indication to provide the time-varying motion command.

37. The system according to claim 33, wherein the actuator is configured to provide a motion-status signal and the controller is further responsive to the motion-status signal to provide the time-varying motion command.

38. The system according to claim 33, wherein the feedback signal includes a drive current of the actuator.

39. The system according to claim 33, wherein the range of positions is divided into a plurality of zones having respective values of a parameter, and the controller is configured to determining the feedback-signal acceptance range by determining one of the zones in which the at least one component is located and determining the feedback-signal acceptance range using the respective parameter value of the determined one of the zones.