Torque balancing scheme for a velocity controlled drive system of a mower
AssigneeFireFly Robotics, Inc.
InventorsGeorge F. Curtis, IV, Eric E. Aston, Mark C. LeBlanc
Life of this patent
Estimating the term…
Abstract
A torque balancing scheme for a velocity controlled drive system of a mower is provided. The torque balancing scheme can be employed on any mower or other similar vehicle having a drive system in which a separate motor is used to independently drive each wheel. By implementing the torque balancing scheme, a drive system can prevent excessive heating of the motors that may otherwise occur when unaccounted-for factors exist.
Claims20
A mower comprising:
- a plurality of wheels for causing the mower to travel with a ground speed, the plurality of wheels including a left front wheel, a left rear wheel, a right front wheel, and a right rear wheel;
- a plurality of motors, wherein each of the plurality of motors rotates a corresponding one of the plurality of wheels, the plurality of motors including a left front motor that rotates the left front wheel, a left rear motor that rotates the left rear wheel, a right front motor that rotates the right front wheel, and a right rear motor that rotates the right rear wheel;
- and
- a controller comprising one or more non-transitory computer storage media storing computer executable instructions which when executed cause the controller to implement a torque balancing scheme comprising:
- obtaining torque measurements for each of the plurality of motors;
- generating a combined torque for each of the plurality of motors using the respective torque measurements;
- generating a left-side front-to-rear comparison from the combined torques for the left front motor and the left rear motor and a right-side front-to-rear comparison from the combined torques for the right front motor and the right rear motor;
- adjusting a left-side velocity correction factor based on the left-side front-to-rear comparison and a right-side velocity correction factor based on the right-side front-to-rear comparison;
- and
- correcting velocities of the left front motor and the left rear motor using the left-side velocity correction factor and velocities of the right front motor and the right rear motor using the right-side velocity correction factor.
One or more non-statutory computer storage media storing computer executable instructions which when executed implement a torque balancing scheme comprising:
- obtaining torque measurements for each of a plurality of motors including a left front motor, a left rear motor, a right front motor, and a right rear motor;
- generating a combined torque for each of the motors using the respective torque measurements;
- generating a left-side front-to-rear comparison from the combined torques for the left front motor and the left rear motor and a right-side front-to-rear comparison from the combined torques for the right front motor and the right rear motor;
- adjusting a left-side velocity correction factor based on the left-side front-to-rear comparison and a right-side velocity correction factor based on the right-side front-to-rear comparison;
- and
- correcting velocities of the left front motor and the left rear motor using the left-side velocity correction factor and velocities of the right front motor and the right rear motor using the right-side velocity correction factor.
A method for balancing torque of a plurality of motors that each independently rotate one of a plurality of wheels, the plurality of motors including a left front motor that rotates a left front wheel, a left rear motor that rotates a left rear wheel, a right front motor that rotates a right front wheel, and a right rear motor that rotates a right rear wheel, the method comprising:
- executing computer executable instructions stored on one or more non-transitory computer storage media to implement a torque balancing scheme, the torque balancing scheme comprising:
- obtaining torque measurements for each of the plurality of motors;
- generating a combined torque for each of the plurality of motors using the respective torque measurements;
- generating a left-side front-to-rear comparison from the combined torques for the left front motor and the left rear motor and a right-side front-to-rear comparison from the combined torques for the right front motor and the right rear motor;
- adjusting a left-side velocity correction factor based on the left-side front-to-rear comparison and a right-side velocity correction factor based on the right-side front-to-rear comparison;
- and
- correcting velocities of the left front motor and the left rear motor using the left-side velocity correction factor and velocities of the right front motor and the right rear motor using the right-side velocity correction factor.
Dependencies are inferred from the claim text.