This paper describes the control, and evaluation of a new human-scaled biped robot with liquid cooled viscoelastic actuators (VLCA). Based on the lessons learned from previous work from our team on VLCA, we present a new system design embodying a Reaction Force Sensing Series Elastic Actuator and a Force Sensing Series Elastic Actuator. These designs are aimed at reducing the size and weight of the robot’s actuation system while inheriting the advantages of our designs such as energy efficiency, torque density, impact resistance and position/force controllability. The robot design takes into consideration human-inspired kinematics and range-of-motion, while relying on foot placement to balance. In terms of actuator control, we perform a stability analysis on a Disturbance Observer designed for force control. We then evaluate various position control algorithms both in the time and frequency domains for our VLCA actuators. Having the low level baseline established, we first perform a controller evaluation on the legs using Operational Space Control. Finally, we move on to evaluating the full bipedal robot by accomplishing unsupported dynamic walking.
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Hybrid Force-Position Control of an Elastic Tendon-Driven Scrubbing Robot (TEDSR)
There is a lack of cleaning robots dedicated to the scrubbing of contaminated surfaces. Contaminated surfaces in domestic and industrial settings typically require manual scrubbing which can be costly or hazardous. There is growing demand for automated sanitization systems in hospitals, foodprocessing plants, and other settings where cleanliness of surfaces is important. To address the opportunity to automate the scrubbing of surfaces, this work focuses on the use of series elastic actuators which can apply consistent trajectories of scrubbing force. Consistent force during scrubbing increases the rate of removal for a contaminant. An elastic robot which has rigid links and low-stiffness joints can perform friction-based cleaning of surfaces with complex geometries while maintaining consistent scrubbing force. This study uses a hybrid forceposition control scheme and a low-cost elastic robot to perform scrubbing. This study observes the relationship between joint stiffness in the robot and the disturbance rejection for force-based control during scrubbing.
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- Award ID(s):
- 2021628
- PAR ID:
- 10524571
- Publisher / Repository:
- ICRA ,Proceedings of 2024 IEEE International Conference on Robotics and Automation
- Date Published:
- Format(s):
- Medium: X
- Location:
- Yokohama, Japan
- Sponsoring Org:
- National Science Foundation
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