Design and multimodal locomotion plan of a hexapod robot with improved knee joints

Hexapod robots represent complex and highly redundant robotic systems capable of handling various tasks in extreme environments, such as planetary exploration and disaster response. To enhance the terrain adaptability and maneuverability of hexapod robots, we present a novel multimodal hexapod robot in this research. Our multimodal hexapod robot design incorporates knee joints with an improved multiparallel quadrilateral transmission mechanism, addressing singularity issues commonly encountered in legged robots. This enhancement not only improves the mechanical transmission characteristics of the knee joints but also increases the workspace of a single leg to achieve leg-arm reuse functionality. In the presence of flat and structured terrain, the robot seamlessly switches to a wheeled locomotion mode, enabling swift traversal. Conversely, when faced with rough and unstructured terrain, it transitions into a legged mode, employing adaptive gait stability to navigate effectively. A novel operational mode in which the hexapod robot utilizes four legs for body support, while the remaining two legs are repurposed as arms is proposed. This innovative approach empowers the hexapod robot to perform dual-arm manipulation without the need for additional degrees of freedom for the manipulator. To validate the effectiveness of our designed hexapod robot and multimodal motion planning algorithm, comprehensive experimental testing has been conducted, demonstrating the practicality and versatility of our system.