Experimental Testing of a Prototype of an Active Elbow Orthosis


Many people have problems with elbow joint driving because of different diseases,
sport trauma, road traffic injuries, etc. A good way for restoring elbow motions is a selfrehabilitation
using an active orthosis. It has to be light, convenient for daily use, active,
easy to control by patients, and safe. The paper presents a prototype of an active elbow
orthosis. The plastic details were designed using a CAD system and were 3D printed.
The joint was driven by a Dynamixel actuator. To increase the joint moment, a reduction
gear-belt drive was constructed and applied. Experiments with six healthy subjects were
performed using a Noraxon measuring system, aiming to investigate elbow joint angles in
natural movements with four different velocities of elbow flexion and extension without and
with a load of 0.5 kg in the hand. The four velocities (from very slow to very fast) were
controlled by a specialized PC application. In order to achieve similar motions of the
orthosis, the angle profiles were approximated so that the motion was between 10 and 120
because of electro/mechanical and software safety stoppers. Experiments were performed
with the orthosis following the given angle profile without load and with a load of 0.5 kg.
The results show that the orthosis’ forearm performs the given angle and angular speed
profiles with enough precision.

Keywords: Elbow, Active orthosis, Rehabilitation, Flexion/extension, Human experiments.

Experimental Testing of Prototype.pdf (952.9 KB)

Academic paper featuring our DYNAMIXEL XH430 all-in-one smart actuators

All credit goes to Silvija Angelova, Emil Petrov, Plamen Raykov and Rositsa Raikova