Measurement of the passive stiffness of ankle joint in 3 DOF using stewart platform type ankle foot device.

This paper presents a method to measure the passive stiffness of an ankle joint in three degrees of freedom (DOF) under two motion speeds (1 Hz and 5 degree/s) using a developed Stewart platform-type device. The developed device can reproduce input motions of the foot in 6 DOF by controlling six pneumatic linear motion actuators. We used the device to measure the passive stiffness of an ankle joint undergoing three kinds of motion, namely dorsi-plantar flexion, inversion-eversion, and adduction-abduction.

Development of Stewart platform type ankle-foot device for trip prevention support.

This paper presents an ankle-foot device using a Stewart platform, which is a type of parallel-link mechanism, for trip prevention support. The developed device can reproduce the input motions of the ankle joint in six degrees of freedom by controlling six pneumatic cylinders at the same time. The root mean square errors of the 3-D position and rotation angle of the reproduced motions with the input motions (dorsiflexion and plantar flexion) were 6.

Evaluation of venous return in lower limb by passive ankle exercise performed by PHARAD.

This paper presents evaluation of venous return, i.e., blood flow volume of vein (BF), in the lower limb after passive exercise performed by our developed "parallel link type human ankle rehabilitation assistive device (PHARAD)".

Development of three-dimensional motion measuring device for the human ankle joint by using parallel link mechanism.

This paper presents a novel ankle motion measuring device that can measure three-dimensional motions without a motion capture system (MCS). We adapted a parallel link mechanism for the device using six wire-type displacement sensors to measure the ankle joint motions in six degrees of freedom (six-DOF). We define the motions of a foot plate which is attached to a foot sole as ankle joint motions.