Controller And Control Method For A Motorised Vehicle

• US 20110071711A1
• Filed: 03/19/2010
• Published: 03/24/2011
• Est. Priority Date: 04/21/2009
• Status: Active Grant

• Current Assignee: Penny and Giles Controls Limited (Curtiss-Wright Corporation)
• Original Assignee: PG Drives Technology Incorporated
• Inventors: Sharp, Nigel Peter, Garnett, Glenn Leigh
• Granted Patent: US 9,211,909 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: A61G 2203/14 Joysticks
• CPC Class Codes: A61G 5/041 having a specific drive-type
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 15/2036 Electric differentials, e.g. for supporting steering vehicles
• CPC Class Codes: B60L 15/34 with human control of a setting device
• CPC Class Codes: B62D 11/003 Electric or electronic control systems
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A controller and control method for a motorised vehicle such a wheelchair are provided. The motorised vehicle has at least two driven wheels driven independently by a motor arrangement, and the controller receives a number of input signals from a user input device of the motorised vehicle. The controller comprises drive control circuitry for generating control signals for controlling the driving of the driven wheels by the motor arrangement, the control signals being dependent on the input signals. Speed assist circuitry is responsive to an indication of current consumed in driving the driven wheels to detect occurrence of a loading condition. On detection of occurrence of a loading condition, the speed assist circuitry is then arranged to boost at least one of the input signals in order to boost top speed in the presence of the loading condition. This significantly improves the control of the motorised vehicle in situations where the occurrence of the loading condition may otherwise prevent the vehicle from moving, as for example may occur when seeking to turn the vehicle at low speed.

Claims

1. A controller for a motorised vehicle, the motorised vehicle having at least two driven wheels driven independently by a motor arrangement, the controller comprising:

an input interface arranged to receive a number of input signals from a user input device of the motorised vehicle;

a drive control circuitry, coupled to the input interface, for generating control signals for controlling the driving of said at least two driven wheels by the motor arrangement, said control signals being dependent on the input signals; and

a speed assist circuitry, responsive to an indication of current consumed in driving at least one of said at least two driven wheels, to detect occurrence of a loading condition;

on detection of occurrence of said loading condition, said speed assist circuitry being arranged to boost at least one of the input signals in order to boost top speed in the presence of said loading condition.

2. A controller as claimed in claim 1, wherein:

said input signals include a top speed setting selectable via the user input device;

the control signals generated by the drive control circuitry are dependent on the top speed setting; and

on detection of occurrence of said loading condition, said speed assist circuitry is arranged to boost said top speed setting selected via the user input device.

3. A controller as claimed in claim 2, wherein:

the top speed setting is selectable between a minimum top speed setting and a maximum top speed setting; and

the speed assist circuitry is arranged on detection of occurrence of said loading condition to raise the minimum top speed setting to create a new minimum top speed setting, such that the amount of boost applied to the top speed setting selected via the user input device is dependent on the value of that selected top speed setting.

4. A controller as claimed in claim 3, wherein the speed assist circuitry is arranged to calculate the new minimum top speed setting by multiplying the minimum top speed setting by a scalar of at least one, the value of the scalar increasing as the current consumed in driving at least one of the at least two driven wheels increases.

5. A controller as claimed in claim 4, further comprising a storage for storing a programmable value, the rate at which the value of the scalar increases as the current consumed in driving at least one of the at least two driven wheels increases being dependent on said programmable value.

6. A controller as claimed in claim 4, wherein the value of the scalar increases linearly with increase in the current consumed in driving at least one of the at least two driven wheels.

7. A controller as claimed in claim 3, wherein when calculating the new minimum top speed setting, the speed assist circuitry restricts the new minimum top speed setting so as not to exceed the maximum speed attainable through said at least two driven wheels.

8. A controller as claimed in claim 3, wherein if the new minimum top speed setting exceeds the maximum top speed setting, the speed assist circuitry is arranged to set the maximum top speed setting to be equal to the new minimum top speed setting.

9. A controller as claimed in claim 1, wherein the speed assist circuitry is arranged only to detect occurrence of the loading condition if at least one predetermined condition exists.

10. A controller as claimed in claim 9, wherein said at least one predetermined condition comprises a condition under which the at least two driven wheels are being driven so as to apply a turning force to the motorised vehicle.

11. A controller as claimed in claim 10, wherein the motor arrangement comprises at least two independent motors for driving said at least two driven wheels, and the at least two driven wheels are driven so as to apply said turning force to the motorised vehicle by driving the at least two independent motors in opposite directions to each other.

12. A controller as claimed in claim 11, wherein the indication of current provided to the speed assist circuitry is an indication of a sum of the absolute value of current consumption in each of said at least two independent motors.

13. A controller as claimed in claim 2, wherein said top speed setting selectable via the user input device comprises a top turn speed setting, and on detection of occurrence of said loading condition, said speed assist circuitry is arranged to boost the top turn speed setting selected via the user input device.

14. A controller as claimed in claim 13, wherein:

the top turn speed setting is selectable between a minimum top turn speed setting and a maximum top turn speed setting; and

the speed assist circuitry is arranged on detection of occurrence of said loading condition to raise the minimum top turn speed setting to create a new minimum top turn speed setting, such that the amount of boost applied to the top turn speed setting selected via the user input device is dependent on the value of that selected top turn speed setting.

15. A controller as claimed in claim 1, wherein the speed assist circuitry is responsive to both said indication of current consumed in driving at least one of said at least two driven wheels, and one or more predetermined operational parameters, to detect occurrence of said loading condition.

16. A controller as claimed in claim 15, wherein said one or more predetermined operational parameters comprise an indication of operating temperature of one or more motors of the motor arrangement used to drive said at least two driven wheels.

17. A controller as claimed in claim 1, wherein said speed assist circuitry detects said loading condition when the current consumed in driving at least one of said at least two driven wheels increases.

18. A controller as claimed in claim 17, wherein said loading condition arises due to friction between at least one of said at least two driven wheels and a surface on which the motorised vehicle is placed when seeking to turn the motorised vehicle increasing the loading on at least one of said at least two driven wheels.

19. A controller as claimed in claim 17, wherein said loading condition arises due to a required re-alignment of castor wheels of the motorised vehicle when seeking to turn the motorised vehicle increasing the loading on at least one of said at least two driven wheels.

20. A controller as claimed in claim 17, wherein said loading condition arises due to weight of the user increasing the loading on at least one of said at least two driven wheels.

21. A controller as claimed in claim 17, wherein said loading condition arises due to contact of the motorised vehicle with an abrupt change in contour of said surface on which the motorised vehicle is placed increasing the loading on at least one of said at least two driven wheels.

22. A controller as claimed in claim 1, for use in a motorised vehicle taking the form of a wheelchair.

23. A controller as claimed in claim 1, wherein the speed assist circuitry is arranged to detect occurrence of the loading condition having regard to an indication of total current consumed in all of said at least two driven wheels.

24. A motorised vehicle comprising:

a motor arrangement;

at least two driven wheels driven independently by said motor arrangement;

a user input device via which a user issues a number of input signals;

a drive control circuitry for generating control signals for controlling the driving of said at least two driven wheels by the motor arrangement, said control signals being dependent on the input signals; and

a speed assist circuitry, responsive to an indication of current consumed in driving at least one of said at least two driven wheels, to detect occurrence of a loading condition;

on detection of occurrence of said loading condition, said speed assist circuitry being arranged to boost at least one of the input signals in order to boost top speed in the presence of said loading condition.

25. A motorised vehicle as claimed in claim 24, wherein said motorised vehicle is a wheelchair.

26. A method of controlling a motorised vehicle having at least two driven wheels driven independently by a motor arrangement, comprising:

receiving a number of input signals from a user input device of the motorised vehicle;

generating control signals for controlling the driving of said at least two driven wheels by the motor arrangement, said control signals being dependent on the input signals;

responsive to an indication of current consumed in driving at least one of said at least two driven wheels, detecting occurrence of a loading condition; and

on detection of occurrence of said loading condition, boosting at least one of the input signals in order to boost top speed in the presence of said loading condition.

27. A computer program product comprising a computer program for executing on a computing device to cause a motorised vehicle having at least two driven wheels driven independently by a motor arrangement to be controlled, on execution on said computing device, code portions of the computer program being arranged:

to receive a number of input signals from a user input device of the motorised vehicle;

to generate control signals for controlling the driving of said at least two driven wheels by the motor arrangement, said control signals being dependent on the input signals;

responsive to an indication of current consumed in driving at least one of said at least two driven wheels, to detect occurrence of a loading condition; and

on detection of occurrence of said loading condition, to boost at least one of the input signals in order to boost top speed in the presence of said loading condition.

28. A controller for a motorised vehicle having at least two driven wheels driven independently by a motor arrangement, the controller being arranged to receive a number of input signals from a user input device of the motorised vehicle, the controller comprising:

drive control means for generating control signals for controlling the driving of said at least two driven wheels by the motor arrangement, said control signals being dependent on the input signals; and

speed assist means, responsive to an indication of current consumed in driving at least one of said at least two driven wheels, for detecting occurrence of a loading condition;

on detection of occurrence of said loading condition, said speed assist means for boosting at least one of the input signals in order to boost top speed in the presence of said loading condition.