• There have been many researches that tried to assist human walking and running. However, the safety factor was not investigated in depth so far, which may also contribute to improving the performance of human walking and running by alleviating their worries on injury. In this perspective, a safety-guaranteeing device was developed in a wearable form factor. Foot is an end-effector, thus the walking and running performance can be significantly affected in either a cognitive or biomechanical way. Rather than granting the system with high stiffness components that can support a large portion of the human body weight, the main goal of this system is to reduce the "likelihood" of steps that may lead to ankle sprain.

• This work involves three main research subsections as below:

1) System design (co-work with Eunsu Lee; UROP): fabricating and realizing the system with a desired wearable form factor, with less than 100g a pair.

2) Vision-based algorithm (co-work with Won Seok Choi; M.S. student): with a ML technique, we developed a practical algorithm run with a single camera attached to a user that can simultaneously distinguish terrain roughness and the user's gait phase.

3) Human studies (co-work with Prof. Jooeun Ahn and his Ph. D. student Jeongin Moon): we have co-developed specially designed shoe add-ons for effectively generating the "instability disturbance", and designed corresponding experimental protocols.