Development of a Low Cost Motion Capture System to Analyze Wrist-Hand Complex

The aim of this article is to describe the development of a low cost motion capture system to analyze the movement of the wrist-hand complex (WHC). First, we searched the relevant literature about resources that could be used to develop a system for capturing motion. Through this search, we opted for the use of a system integrating an electronic platform and sensors (flexsensor and stretchsensor) that are able to capture the movements of WHC. A program written in the Processing 1.2.1 language was developed to allow the interpretation of the information obtained by the sensors and the electronic platform by the computer. Then, we defined the type, size and position of each sensor to capture the movement of each single joint of the WHC and the forearm movements of prone/supine. The prototype system proved to be a viable tool to test movements of the WHC. The results indicated that the proposed system could be useful to analyze movements of the WHC. On the other hand, the necessity of a wire connection from the sensors to the electronic platform and from the platform to a computer, the small numbers of analogical input of the developed electronic platform, the mechanical fragility of the sensors, and difficulty to evaluate the complex movement of opposition of the fingers can be limitations to this system. Another limitation of the system is its calibration. To overcome this problem, we intent to use measures of angles instead of the electrical resistance of the sensors.