Conjugate momentum based thruster force estimate in dynamic multimodal robot

Shreyansh Pitroda; Eric Sihite; Taoran Liu; Kaushik Venkatesh Krishnamurthy; Chenghao Wang; Adarsh Salagame; Reza Nemovi; Alireza Ramezani; Morteza Gharib

arXiv · 2411.14596

Conjugate momentum based thruster force estimate in dynamic multimodal robot

Shreyansh Pitroda·Eric Sihite·Taoran Liu·Kaushik Venkatesh Krishnamurthy·Chenghao Wang·Adarsh Salagame·Reza Nemovi·Alireza Ramezani·Morteza Gharib

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Abstract

In a multi-modal system which combines thruster and legged locomotion such our state-of-the-art Harpy platform to perform dynamic locomotion. Therefore, it is very important to have a proper estimate of Thruster force. Harpy is a bipedal robot capable of legged-aerial locomotion using its legs and thrusters attached to its main frame. we can characterize thruster force using a thrust stand but it generally does not account for working conditions such as battery voltage. In this study, we present a momentum-based thruster force estimator. One of the key information required to estimate is terrain information. we show estimation results with and without terrain knowledge. In this work, we derive a conjugate momentum thruster force estimator and implement it on a numerical simulator that uses thruster force to perform thruster-assisted walking.

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Shreyansh Pitroda, Eric Sihite, Taoran Liu, Kaushik Venkatesh Krishnamurthy, Chenghao Wang, Adarsh Salagame, Reza Nemovi, Alireza Ramezani, Morteza Gharib. 2024-11-21. Conjugate momentum based thruster force estimate in dynamic multimodal robot. https://arxiv.org/abs/2411.14596

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