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Published on: July 10, 2019
Multi-Phase Joint-Angle Trajectory Generation Inspired by Dog Motion for Control of Quadruped Robot
1Department of Robotics Engineering, Yeungnam University, Gyeongsan 38541, Korea.
This study introduces a novel algorithm for quadruped robot leg trajectory generation, enabling smooth transitions between gaits like walking and galloping. The method uses fuzzy logic for continuous gait phase changes, enhancing locomotion control.
Area of Science:
- Robotics
- Control Systems
- Biomechanics
Background:
- Quadruped robots offer advantages in speed, payload, and stability over humanoids, but complex locomotion and gait transitions remain challenging.
- Existing trajectory generation methods often lack sufficient degrees of freedom for seamless gait transitions or fail to account for speed-dependent gait changes.
Purpose of the Study:
- To propose a multi-phase joint-angle trajectory generation algorithm for quadruped robots.
- To enable smooth and continuous transitions between various gait phases (walk, amble, trot, canter, gallop) across different locomotion speeds.
Main Methods:
- Expressing quadruped joint angles using cyclic basis functions with manipulated inputs.
- Formulating a synchronization function to ensure proper leg sequencing and ground contact.
- Utilizing fuzzy logic to manage discrete gait phase classifications and ensure continuous joint-angle trajectories during transitions.
Main Results:
- The proposed algorithm successfully generates joint-angle trajectories for multiple gait phases.
- Fuzzy logic integration facilitates smooth and continuous transitions between discrete gait phases.
- Simulation studies validate the effectiveness of the multi-phase trajectory generation method.
Conclusions:
- The developed algorithm provides a robust solution for complex gait transitions in quadruped robots.
- The approach enhances locomotion control by enabling seamless adaptation to varying speeds and gait requirements.
- This research contributes to more versatile and adaptable quadruped robot locomotion systems.
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