An investigation on the role of tarsal flexibility in insect walking

• Main Author: Tjuatja, Johan
• Other Authors: Hirotaka Sato
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/78778
• Institution: Nanyang Technological University

Insect leg is a field that has been widely studied by scientists. Although there is a wealth of literature on various physical properties of insect leg, such as strength and inner structure, there seems to be a lack of knowledge on the functions or roles of the individual leg segments, such as the tarsus. While the tarsus has been long known to be flexible, there has currently been no study that explains what the purpose of this flexibility is in insect leg. As such, this project aims to investigate the possible roles that tarsal flexibility plays in insect walking. The study is done by removing tarsal flexibility in insect legs via applying heat shrink tube on the tarsi of chosen beetles, and then observing how it impacts the walking of the beetles. The result of the experiment shows that two out of three experimental beetles ‘struggled’ to walk after the removal of their tarsal flexibility. Prior to this removal of tarsal flexibility, the beetles were able to walk without any issue. Coupled with the results from an auxiliary study on the kinematic behavior of the tarsal during walking, it can be concluded that one possible role of the flexibility in the tarsus is to enable insects to detach their claws from uneven walking surface where claws attachments are involved in walking. Currently, the method used to differentiate between ‘normal’ and ‘struggle’ walking is rather qualitative. Future studies into this area should develop a more quantitative method to perform such differentiation.