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US 2021/0229279 A1Published application
Hybrid control of a robotic system
AssigneeThe Cleveland Clinic Foundation
InventorsRobb Colbrunn, Tara Nagle, Callan Gillespie
Life of this patent
Estimating the term…
Abstract
An object can be moved via a robotic system with a combination of force and position control. The control system can include the object to be moved, the robotic system that moves the object, at least one force sensor, at least one position sensor, and a controller. A position control output, a force control output, and a hybrid weighting value can each be determined by the controller based on sensor data and then combined to determine an amount of position control and/or force control to be applied to move the object and/or modify an object in motion's trajectory.
Claims20
A system comprising:
- at least one object configured to be moved by a robotic system;
- at least one force sensor configured to be positioned on the at least one object to measure actual forces associated with the at least one object;
- at least one position sensor configured to be positioned on the at least one object to measure an actual position associated with the at least one object;
- and
- a controller comprising:
- a non-transitory memory storing executable instructions;
- and
- a processor for executing the instructions to:
- receive, from the at least one force sensor, the actual forces associated with the at least one object;
- receive, from the at least one position sensor, the actual position associated with the at least one object;
- retrieve desired forces to be associated with the at least one object, wherein the desired forces and the actual forces are each within a first coordinate system;
- retrieve a desired position to be associated with the at least one object, wherein the desired position and the actual position are each within a second coordinate system;
- retrieve a trajectory of the at least one object based on the desired forces and the desired position;
- establish a common reference frame for the actual forces, the actual position, the desired forces, and the desired position;
- transform the actual forces, the actual position, the desired forces, and the desired position from the respective first coordinate system and second coordinate system to the common reference frame;
- determine a force control output based on the difference between the actual force and the desired force;
- determine a position control output based on the difference between the actual position and the desired position;
- determine a hybrid weighting value based on an amount of position control required for the at least one object to reach the desired position at the desired forces at a future time and an amount of force control required for the at least one object to reach the desired position at the desired forces at the future time, wherein the hybrid weighting value is variable in time based on at least one control variable;
- determine a change in position associated with the at least one object and a change in forces associated with the at least one object based on the hybrid weighting value, the force control output, and the position control output;
- modify the trajectory of the at least one object based on the change in position and the change in forces associated with the at least one object;
- and
- move the at least one object based on the modified trajectory.
19 more elements
A method of moving at least one object comprising:
- receiving, by a controller comprising a processor, actual forces associated with the at least one object in a first coordinate system, the actual forces being measured by at least one force sensor positioned on the at least one object;
- receiving, by the controller, an actual position associated with the at least one object in a second coordinate system, the actual position being measured by at least one position sensor positioned on the at least one object;
- retrieving, by the controller, desired forces to be associated with the at least one object, wherein the desired forces are input into the system in the first coordinate system;
- retrieving, by the controller, a desired position to be associated with the at least one object, wherein the desired position is input into the system in the second coordinate system;
- retrieving, by the controller, a trajectory of the at least one object based on the desired forces and the desired position;
- establishing, by the controller, a common reference frame for the actual forces, the actual position, the desired forces, and the desired position;
- transforming, by the controller, the actual forces, the actual position, the desired forces, and the desired position from the respective first coordinate system and second coordinate system to the common reference frame;
- determining, by the controller, a force control output based on the difference between the actual force and the desired force;
- determining, by the controller, a position control output based on the difference between the actual position and the desired position;
- determining, by the controller, a hybrid weighting value based on an amount of position control required for the at least one object to reach the desired position at the desired forces at a future time and an amount of force control required for the at least one object to reach the desired position at the desired forces at the future time, wherein the hybrid weighting value is variable in time based on at least one control variable;
- determining, by the controller, a change in position and a change in forces associated with the at least one object based on the hybrid weighting value, the force control output, and the position control output;
- modifying, by the controller, the trajectory of the at least one object based on the change in position and the change in forces associated with the at least one object;
- and
- moving, by a robotic system associated with the controller, the at least one object based on the modified trajectory.
11 more elements
Dependencies are inferred from the claim text.