Lawn tractor with electronic drive and control system

• US 10,058,031 B1
• Filed: 06/30/2017
• Issued: 08/28/2018
• Est. Priority Date: 02/28/2015
• Status: Active Grant

• Current Assignee: Hydro-Gear Limited Partnership
• Original Assignee: Hydro-Gear Limited Partnership
• Inventors: Brown, Alyn G., McCoy, K. Mike, Moebs, Gregory Barton, Arends, Gregory E., Hoyda, Damon J., Probst, Jesse L., Hamilton, Joseph
• Primary Examiner(s): Martinez, David E
• Application Number:
  US15/640,300
• Time in Patent Office: 424 Days
• Field of Search: None
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/006 Control or measuring arrangements
• CPC Class Codes: A01D 34/66 with two or more cutters
• CPC Class Codes: A01D 69/02 electric
• CPC Class Codes: A01D 69/025 Electric hybrid systems
• CPC Class Codes: B60K 17/00 Arrangement or mounting of transmissions in vehicles clutches per se, e.g. construction thereof, F16D; gearing per se, e.g. construction thereof, F16H
• CPC Class Codes: B60K 17/14 the motor of fluid or electric gearing being disposed in or adjacent to traction wheel B60K7/00 takes precedence
• CPC Class Codes: B60K 17/356 having fluid or electric motor, for driving one or more wheels disposition of motor in, or adjacent to, traction wheel B60K7/00
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: B60K 7/0015 the motor being hydraulic
• CPC Class Codes: B60R 16/0231 Circuits relating to the driving or the functioning of the vehicle monitoring tyres B60C23/00; indicating overspeed B60K31/00; for dash boards B60K37/00, B60Q3/10; for indicating emergencies B60Q1/52; brake control systems B60T; registering or indicating the working of vehicles G07C5/00; measuring distance G01C, e.g. combinations of speed and distance G01C23/00; engine indicators G01L; measuring speed or acceleration G01P
• CPC Class Codes: B60Y 2200/221 Tractors
• CPC Class Codes: B60Y 2200/223 Ridable lawn mowers
• CPC Class Codes: B60Y 2400/30 Sensors

Abstract

A lawn tractor includes one or more sensors configured to detect an operational parameter of an aspect of the vehicle, and one or more controllers for controlling one or more components of the vehicle and for receiving data output from the one or more sensors. The controller communicates with the one or more sensors and one or more vehicle modules configured to control one or more vehicle components via a CAN Bus network. The controller may be coupled to an IMU mounted on the vehicle for dynamically controlling the vehicle on sloped terrain, for example. The controller may be accessible from a remote device over a wireless network for communicating setup, diagnostic, and performance data to and from the vehicle.

Claims

1. A lawn tractor, comprising:

a frame on which an internal combustion engine is mounted;

a CAN-Bus network operable to communicate signals to and from one or more components of the lawn tractor;

a vehicle control module comprising a processor and memory and operable to receive a plurality of analog input signals and a plurality of digital input signals from one or more components of the lawn tractor and to transmit digital output signals via the CAN-Bus network to one or more components of the lawn tractor,

first and second drive systems comprising

(a) first and second traction wheels disposed on opposing sides of the frame;

(b) first and second hydrostatic transaxles comprising first and second output axles connected to the respective first and second traction wheels;

(c) first and second electric actuators with integrated first and second electronic drive modules mounted to the respective first and second hydrostatic transaxles for controlling an output speed and direction of motion of the first and second hydrostatic transaxles;

first and second steering and drive control levers for receiving user input regarding desired speed and direction of motion of the lawn tractor;

first and second steering lever sensor modules connected to the respective first and second steering and drive control levers for detecting position, speed and direction of motion of the first and second steering and drive control levers and operable to post on the CAN-Bus network first and second lever signals corresponding to the position, speed and direction of motion of the respective first and second steering and drive control levers;

wherein the vehicle control module is configured to process the first and second lever signals and post on the CAN-Bus network first and second digital drive signals configured to obtain the desired speed and direction of motion of the lawn tractor,

wherein the first and second electronic drive modules are configured to process the first and second digital drive signals and convert the first and second digital drive signals to appropriate first and second actuator signals to drive the first and second electric actuators to obtain the desired speed and direction of motion of the lawn tractor.

2. The lawn tractor of claim 1, wherein the first and second electronic drive modules are configured to continuously compare actual first and second electric actuator positions to the position, speed and direction of motion detected by the first and second steering lever sensor modules, and update the first and second actuator positions to approximate the position, speed and direction of motion detected by the first and second steering lever sensor modules.

3. The lawn tractor of claim 1, wherein the first and second electronic drive modules are configured to use a motion profile algorithm based on tunable parameters stored in memory on each of the first and second electronic drive modules to individually drive the first and second electric actuators.

4. The lawn tractor of claim 1, wherein the vehicle control module includes an interface for receiving the plurality of analog input signals from a plurality of analog input devices.

5. The lawn tractor of claim 4, wherein the plurality of analog input devices includes a seat occupancy sensor configured to detect presence of weight on a seat of the lawn tractor, wherein the seat occupancy sensor is configured to post on the CAN-Bus network an activation signal corresponding to the presence of weight on a user'"'"'s seat mounted on the lawn tractor and wherein the vehicle control module is configured to respond to the activation signal.

6. The lawn tractor of claim 4, wherein the plurality of analog input devices includes a PTO engagement sensor configured to detect an “

on”

or “

off”

engagement status of a PTO device, wherein the PTO engagement sensor is configured to post on the CAN-Bus network an “

on”

or “

off”

engagement signal corresponding to the “

on”

or “

off”

engagement status of the PTO device and wherein the vehicle control module is configured to respond to the “

on”

or “

off”

engagement signal.

7. The lawn tractor of claim 4, wherein the plurality of analog input devices includes a parking brake engagement sensor configured to detect an “

on”

or “

off”

engagement status of a parking brake, wherein the parking brake engagement sensor is configured to post on the CAN-Bus network an “

on”

or “

off”

engagement signal corresponding to the “

on”

or “

off”

engagement status of the parking brake and wherein the vehicle control module is configured to respond to the “

on”

or “

off”

engagement signal.

8. The lawn tractor of claim 4, wherein the plurality of analog input devices includes a key switch from which the vehicle control module obtains electrical power, wherein the vehicle control module is configured to receive electrical power when the key switch is in the “

on”

position and to cease receiving electrical power when the key switch is in the “

off”

position, wherein when the key switch is in the “

on”

position, the vehicle control module provides electrical power to energize the CAN-Bus network.

9. The lawn tractor of claim 4, wherein the plurality of analog input devices includes first and second neutral switches connected to the respective first and second steering and drive control levers for detecting a neutral and non-neutral position of the respective first and second steering and drive control levers, wherein the first and second neutral switches are configured to post on the CAN-Bus network the “

neutral” and

the “

non-neutral”

position of the first and second neutral switches and wherein the vehicle control module is configured to respond to the “

neutral” and

the “

non-neutral”

position.

10. The lawn tractor of claim 1, including a user interface module comprising a display screen connected to the CAN-Bus network and configured to display lawn tractor status information messages generated by the vehicle control module that are posted to the CAN-Bus network.

11. The lawn tractor of claim 10, wherein the display screen is a touch screen configured to receive user input that is posted on the CAN-Bus network.

12. The lawn tractor of claim 1, including a stability control module coupled to the vehicle control module, the stability control module configured to provide vehicle straight line tracking, wheel slip and traction control, hillside stability, and rollover protection during operation of the lawn tractor.

13. The lawn tractor of claim 12, wherein the stability control module includes an inertial measurement unit module configured to post on the CAN-Bus network a digital attitude and heading reference signal corresponding to detected attitude and heading motion of the lawn tractor for use by the vehicle control module.

14. The lawn tractor of claim 13, wherein the digital attitude and heading reference signal is obtained by the fusion of output signals from a multi-axis accelerometer, a multi-axis gyroscope, and a multi-axis magnetometer.

15. The lawn tractor of claim 14, wherein the fusion of output signals results in a vector in 3 dimensions.

16. The lawn tractor of claim 1, wherein the vehicle control module is configured to send, via the CAN-Bus network, a control signal to the first and second electronic drive modules to reduce the speed of the lawn tractor to a predetermined speed irrespective of the detected position, speed and direction of motion of the first and second steering and drive control levers.

17. The lawn tractor of claim 1, wherein the vehicle control module is configured to disable a start relay of the engine.

18. The lawn tractor of claim 1, wherein the vehicle control module is configured to disable an engine kill relay.

19. The lawn tractor of claim 1, wherein the vehicle control module includes a Bluetooth module for wireless communications to and from the lawn tractor.

20. The lawn tractor of claim 1, wherein the vehicle control module provides electrical power to energize the CAN-Bus network.