Dong-Jun Lee

Dr. Dong-Jun Lee

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 July 2020 in IEEE Robotics and Automation Letters
Verified
Journal Article
Closed access
Dong-Jun LeeDong-Jun Lee
Dong-Jun Lee
Gwang-Pil JungGwang-Pil Jung
Gwang-Pil Jung
Chameleon tongue-like manipulators have the potential to be quite useful for mobile systems to overcome access issues by allowing them to reach distant targets in an instant. For example, a quadrotor with this manipulator will be able to snatch distant targets instead of hovering and picking up. In this letter, we present a chameleon-inspired shooting and rapidly retracting manipulator, which is lightweight, compact, and ultimately suitable for mobile systems. To make this possible, two design strategies are proposed: to use a wind-up spring as an energy source and to employ an active clutch to selectively distribute the energy. The wind-up spring enables the device to keep supplying the stored energy for a long time, compared to normal torsion springs. The active clutch controls the direction and the timing of the energy supply, which allows to deploy and retract the end-effector. Thanks to these design strategies, the device achieves snatching manipulation while maintaining compact and lightweight. In result, the Snatcher has a size of 120x85x85mm, weighs 117.48g, and brings a 30g mass located at 0.8m away within 600ms.

1 August 2023 in Biomimetics
Verified
Journal Article
Open access
PDF file
SYSeon-Gyo Yang
Seon-Gyo Yang
Dong-Jun LeeDong-Jun Lee
Dong-Jun Lee
CKChan Kim
Chan Kim
Gwang-Pil JungGwang-Pil Jung
Gwang-Pil Jung
Hopping locomotion has the potential to enable small-scale robots to maneuver lands quickly while overcoming obstacles bigger than themselves. To make this possible, in this paper, we propose a novel design of a high-power linear actuator for a small-scale hopper. The key design principle of the linear actuator is to use a power spring and an active clutch. The power spring provides a near constant torque along the wide range of output displacement. The active clutch controls the moving direction and operation timing of the linear actuator, which enables the hopper to take off at the right timing. As a result, the hopper has a size of 143 mm, a mass of 45.9 g, and hops up to 0.58 m.