	US 12,270,179 B2
	Systems and methods of force balancing for actuators of a power machine
Christopher Young, Fargo, ND (US)
Assigned to Doosan Bobcat North America, Inc., West Fargo, ND (US)
Filed by Doosan Bobcat North America, Inc., West Fargo, ND (US)
Filed on Aug. 30, 2024, as Appl. No. 18/821,761.
Claims priority of provisional application 63/580,063, filed on Sep. 1, 2023.
Prior Publication US 2025/0075463 A1, Mar. 6, 2025
Int. Cl. E02F 3/43 (2006.01)

CPC E02F 3/434 (2013.01)

20 Claims

1. An electric power machine, the electric power machine comprising:

a power machine frame;

a plurality of electric actuators supported by the power machine frame, wherein the plurality of electric actuators includes a set of electric lift actuators and a set of electric tilt actuators;

a lift arm structure that includes:

a lift arm coupled to the power machine frame and configured to be moved relative to the power machine frame by the set of electric lift actuators; and

a work element supported by the lift arm and configured to be moved relative to the lift arm by the set of electric tilt actuators;

an electrical power source configured to power the plurality of electric actuators; and

one or more electronic processors in communication with the plurality of electric actuators, the one or more electronic processors configured to:

receive a command for movement of the lift arm using the set of electric lift actuators or movement of the work element using the set of electric tilt actuators; and

control, based on the command, the set of electric lift actuators or the set of electric tilt actuators to, respectively, substantially balance forces between the set of electric lift actuators or substantially balance forces between the set of electric tilt actuators.

8. A method for controlling an electric power machine, the method comprising:

receiving, with one or more electronic processors, a command to perform an operation with a plurality of electric actuators of the electric power machine, the plurality of electric actuators including a first electric actuator and a second electric actuator;

controlling, with the one or more electronic processors, the first electric actuator based on a velocity control parameter to perform the operation;

determining, with the one or more electronic processors, a target electric current for the second electric actuator based on a present electric current of the first electric actuator while the first electric actuator is controlled based on the velocity control parameter to perform the operation; and

controlling, with the one or more electronic processors, the second electric actuator based on the target electric current to perform the operation.

14. A method for controlling an electric power machine, the method comprising:

receiving, with one or more electronic processors, a command for controlling a work element with a plurality of electric actuators of the electric power machine;

determining, with the one or more electronic processors, a target velocity for the plurality of electric actuators based on the command;

controlling, with the one or more electronic processors, the plurality of electric actuators based on the target velocity;

while controlling the plurality of electric actuators based on the target velocity, monitoring, with the one or more electronic processors, electric currents of a first electric actuator and a second electric actuator of the plurality of electric actuators to detect an electric current difference between the electric currents of the first electric actuator and the second electric actuator; and

responsive to detecting the electric current difference:

determining, with the one or more electronic processors, a first adjusted target velocity for the first electric actuator; and

controlling, with the one or more electronic processors, the first electric actuator based on the first adjusted target velocity.