Wearable Robots ( 2010 ~ )

Exoskeleton : Robowear (2010 ~ 2011)

Wearable robots, or exoskeleton robots, are getting great attention because of the increasing need for seniors, disabled people, and workers in extreme environments. One of the most important requirements of the exoskeleton robot is preventing fatigues of these people. Although exoskeleton robots have been developed, there are still limitations on the user’s comfort and detection of his or her intention of motion. To improve on these aspects, spiral spring and sensor band are proposed to be used as actuation and sensor components in this paper. The spiral spring’s efficiency for wearable robots is investigated theoretically and the experiments using the spiral spring and sensor band are conducted. The experimental results demonstrate the proposed actuation and sensor system could improve the performance of the exoskeleton robots.



Compliant Actuators : DSSAS (2011 ~ )

The main motivation behind the creation of a compliant actuation system is to provide safety, capability with storing energy, and improved performance levels of dynamic tasks. The choice of the proper compliance level pertaining to robots depends on the specific purposes of the robots. In this paper, a dual-spiral-spring actuation system (DSSAS) is proposed to provide large compliance and deformation for wearable robots. Among the many different applications of wearable robotic systems, we aim for systems in which safety and compliance are more important than the control bandwidth of the joints. A spiral spring is selected to take advantage of the characteristics of high levels of compliance and deformation compared to other elastic components. The proposed dual-spiral-spring actuation system uses two spiral springs in opposite directions, as the spiral spring generates torque only in one direction. First, we present the characteristics of the spiral spring for a compliant joint. Then, the design and performance of the DSSAS are demonstrated by experiments.



Compliant Exoskeleton : DSSAS for Exoskeleton (2012 ~ )

The DSSAS was developed for wearable robots. It is arguable as to whether high stiffness or low stiffness is better for general wearable robots. However, the joint compliance can be different for specific wearable robots depending on their purposes. The large compliance of the DSSAS limits the bandwidth of the joint torque control, which is constrained by the motor bandwidth. This is the trade-off between the compliance and the bandwidth in joint actuation. Thus, the DSSAS can be used for several specific applications among many wearable robotic systems.