The original Myoelectric Training Tool (MTT) is both functional and inexpensive, but has an un-anatomical appearance and limited payload. To overcome these issues an improved robotic arm, called the “Bento Arm”, was designed specifically for myoelectric training and research applications. The Bento Arm includes five (5) degrees of freedom (shoulder rotation, elbow flexion, wrist rotation, wrist flexion, hand open/close) to match both commercially available and future anticipated myoelectric components.

The arm was designed to be 1:1 scale to anatomical proportions. The stronger MX-series of Dynamixel actuators allow for increased payloads and include integrated position and velocity joint feedback and control. Anthropomorphic arm shells were designed using 3D scanning technology to improve the aesthetics of the arm and allow it to be more easily visualized as an arm. A quick disconnect wrist was specified as the wrist connector to allow commercial myoelectric hands to be interchanged with custom grippers.

Two different software interfaces for the Bento Arm were developed including one that uses MATLAB’s xPC target with a Windows Graphical User Interface (GUI) and another that uses Robotic Operating System (ROS) with a Linux GUI. The prototype of the Bento Arm was 3D printed and tested with the ROS interface and was fitted with a SensorHand Speed (Ottobock, Inc.). Although the arm was primarily designed to be desk mounted we have also interfaced the prototype to a transhumeral socket to verify that it can be worn by amputee subjects in research trials.

Please check out the development page for the Bento Arm.