Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains
As legged robots are sent into unstructured environments, the ability to robustly manage contact transitions will be a critical skill. This paper introduces an approach to probabilistically fuse contact models, managing uncertainty in terrain geometry, dynamic modeling, and kinematics to improve the...
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| Format: | Article |
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Institute of Electrical and Electronics Engineers (IEEE)
2019
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| Online Access: | http://hdl.handle.net/1721.1/120350 https://orcid.org/0000-0001-7137-5932 https://orcid.org/0000-0002-0218-6801 |
| _version_ | 1826198871629365248 |
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| author | Wensing, Patrick M. Bledt, Gerardo Ingersoll, Samuel Kim, Sangbae |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Wensing, Patrick M. Bledt, Gerardo Ingersoll, Samuel Kim, Sangbae |
| author_sort | Wensing, Patrick M. |
| collection | MIT |
| description | As legged robots are sent into unstructured environments, the ability to robustly manage contact transitions will be a critical skill. This paper introduces an approach to probabilistically fuse contact models, managing uncertainty in terrain geometry, dynamic modeling, and kinematics to improve the robustness of contact initiation at touchdown. A discrete-time extension of the generalized-momentum disturbance observer is presented to increase the accuracy of proprioceptive force control estimates. This information is fused with other contact priors under a framework of Kalman Filtering to increase robustness of the method. This approach results in accurate contact detection with 99.3 % accuracy and a small 4-5ms delay. Using this new detector, an Event-Based Finite State Machine is implemented to deal with unexpected early and late contacts. This allows the robot to traverse cluttered environments by modifying the control actions for each individual leg based on the estimated contact state rather than adhering to a rigid time schedule regardless of actual contact state. Experiments with the MIT Cheetah 3 robot show the success of both the detection algorithm, as well as the Event-Based FSM while making unexpected contacts during trotting. |
| first_indexed | 2024-09-23T11:10:58Z |
| format | Article |
| id | mit-1721.1/120350 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T11:10:58Z |
| publishDate | 2019 |
| publisher | Institute of Electrical and Electronics Engineers (IEEE) |
| record_format | dspace |
| spelling | mit-1721.1/1203502022-09-27T17:42:37Z Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains Wensing, Patrick M. Bledt, Gerardo Ingersoll, Samuel Kim, Sangbae Massachusetts Institute of Technology. Department of Mechanical Engineering Bledt, Gerardo Ingersoll, Samuel Kim, Sangbae As legged robots are sent into unstructured environments, the ability to robustly manage contact transitions will be a critical skill. This paper introduces an approach to probabilistically fuse contact models, managing uncertainty in terrain geometry, dynamic modeling, and kinematics to improve the robustness of contact initiation at touchdown. A discrete-time extension of the generalized-momentum disturbance observer is presented to increase the accuracy of proprioceptive force control estimates. This information is fused with other contact priors under a framework of Kalman Filtering to increase robustness of the method. This approach results in accurate contact detection with 99.3 % accuracy and a small 4-5ms delay. Using this new detector, an Event-Based Finite State Machine is implemented to deal with unexpected early and late contacts. This allows the robot to traverse cluttered environments by modifying the control actions for each individual leg based on the estimated contact state rather than adhering to a rigid time schedule regardless of actual contact state. Experiments with the MIT Cheetah 3 robot show the success of both the detection algorithm, as well as the Event-Based FSM while making unexpected contacts during trotting. 2019-02-13T14:44:05Z 2019-02-13T14:44:05Z 2018-09 2018-05 2018-12-10T20:30:06Z Article http://purl.org/eprint/type/ConferencePaper 978-1-5386-3081-5 http://hdl.handle.net/1721.1/120350 Bledt, Gerardo, Patrick M. Wensing, Sam Ingersoll, and Sangbae Kim. “Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains.” 2018 IEEE International Conference on Robotics and Automation (ICRA), 21-25 May 2018, Brisbane, Queensland, Australia, IEEE, 2018. https://orcid.org/0000-0001-7137-5932 https://orcid.org/0000-0002-0218-6801 http://dx.doi.org/10.1109/ICRA.2018.8460904 2018 IEEE International Conference on Robotics and Automation (ICRA) Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Institute of Electrical and Electronics Engineers (IEEE) Other repository |
| spellingShingle | Wensing, Patrick M. Bledt, Gerardo Ingersoll, Samuel Kim, Sangbae Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains |
| title | Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains |
| title_full | Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains |
| title_fullStr | Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains |
| title_full_unstemmed | Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains |
| title_short | Contact Model Fusion for Event-Based Locomotion in Unstructured Terrains |
| title_sort | contact model fusion for event based locomotion in unstructured terrains |
| url | http://hdl.handle.net/1721.1/120350 https://orcid.org/0000-0001-7137-5932 https://orcid.org/0000-0002-0218-6801 |
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