Multi-modal locomotion

Loading Physical Intelligence Department


Approach: Analyze biological systems which demonstrate not only the desired locomotion modes but also significant levels of integration between the modes. The integration concepts are then abstracted from the organism and applied to the development of a robotic system.


Benefits: Employing multiple locomotion strategies can significantly improve the mobility of systems operating in unstructured terrain. By utilizing an integrated approach for the addition of locomotion modes, the performance of individual modes can be preserved while reducing the additional structure and actuation required therefore, improving overall system performance.


Mobility in unstructured environments is a significant challenge for robotic systems; however, there are systems capable of operation in these environments, namely biological systems. Even though technology does not allow for replication, with the correct level of abstraction, these systems can inspired design strategies which can improve the performance of their robotic counterparts.


Major Challenges (small scale robots): 1) Energy, actuation, and transmission components are relatively large, heavy, and inefficient. 2) Obstacle size is comparable to that of the robot requiring significant variation in locomotion modes. 3) Unstructured environments require highly adaptable modes.


Goal: To identify, analyze, and develop integration strategies for the combination of high performance locomotion modes as well as the key components within these strategies.


Project Members:

Matthew Woodward

Selected Research Results and Papers

MultiMo-Bat: A biologically inspired integrated jumping-gliding robot

This paper presents the design, development, and verification of a miniature integrated jumping and gliding robot, the MultiMo-Bat, which is inspired by the locomotion strategy of vampire bats. This 115.6 gram robot exhibits high jumping and gliding performance, reaching heights of over 3 meters, to overcome obstacles in the environment. The MultiMo-Bat was developed by a novel integrated design strategy that combines jumping and gliding locomotion modes and minimizes the necessary actuation and structural components by sharing a significant portion of the components required for each mode; nearly 70% of the total robot mass is utilized by both modes. This results in overall low mass, low volume, and high cooperation between the modes which allows for the preservation of over 80% of the performance of the independent jumping locomotion mode when combined. This not only allows for two high performance locomotion modes but also for all of the necessary actuation components to be on-board. Key considerations and components of the design are discussed in the context of the integrated design approach. A prototype of the system is constructed and experimentally tested in various configurations to elucidate the overall system and integration performance. Finally, metrics are developed to begin to quantify the level and performance of the integrated approach as well as allow it to be compared to other mechanical and biological systems. This type of jumping and gliding robot can be used to explore, inspect, and monitor unstructured environments for security and environment monitoring applications.

Woodward MA and Sitti M (2014) MultiMo-Bat: A biologically inspired integrated jumping-gliding robot. The International Journal of Robotics Research 33(12), 1511-1529

Brief highlighted research result:

This paper has several broader impacts most notably the demonstration of a high performance, highly dynamic robotic system with multiple locomotion modes. This is achieved through the integration of the gliding mode which preserves a significant percentage of the jumping mode's performance. Secondary contributions include the development of flexible airfoils, optimal spring design, high energy storage devices, passive transition between jumping and gliding modes, and integrated design metrics.

List of Publications

MultiMo-Bat: A biologically inspired integrated jumping–gliding robot

MA Woodward, M Sitti

The International Journal of Robotics Research 33 (12), 1511-1529



Design of a miniature integrated multi-modal jumping and gliding robot

MA Woodward, M Sitti

Intelligent Robots and Systems (IROS), 2011 IEEE/RSJ International ...