To improve the robustness of human motion synthesis and capture algorithms, our goal is to provide an effective framework for imposing joint limits and reducing ambiguities. To this end, we determine these joint limits from measures performed on human subjects and then transpose them to an intuitive joint limits formalism. Here we focus on the case of ball-andsocket joint limits, applied to the...

BACKGROUND Many prior studies have evaluated shoulder motion, yet no three-dimensional analysis comparing the combined clavicular, scapular, and humeral motion during arm elevation has been done. We aimed to describe and compare dynamic three-dimensional motion of the shoulder complex during raising and lowering the arm across three distinct elevation planes (flexion, scapular plane abduction, ...

[Purpose] Increased plantar pressure during walking is a risk factor for foot ulcers because of reduced range of motion at the ankle and first metatarsophalangeal joints. However, the range of motion in patients undergoing hemodialysis has not yet been determined. A cross-sectional study was performed to investigate the factors affecting the range of motion of the ankle and first metatarsophala...

We have been developing exoskeletal robots in order to assist the motion of physically weak persons such as elderly persons or handicapped persons. In our previous research, a prototype of a two degree of freedom exoskeletal robots for shoulder joint motion assist have been developed since the shoulder motion is especially important for people to take care of themselves in everyday life. In thi...

During multijoint limb movements such as reaching, rotational forces arise at one joint due to the motions of limb segments about other joints. We report the results of three experiments in which we assessed the extent to which control signals to muscles are adjusted to counteract these "interaction torques." Human subjects performed single- and multijoint pointing movements involving shoulder ...