Design and Development of a Test System for an Artificial Limb Controller
Examensarbete för masterexamen
Biomedical engineering (MPBME), MSc
Abstract Implanted muscular electrodes offer a promising method for controlling Artificial Limbs (ALs) and, when combined with an Osseointegrated Implant System (OIS), can significantly enhance the lives of amputees. However, the control of ALs with electromyography (EMG) data is complex and requires an advanced control system. Testing of such a system is an iterative process and is difficult to perform without utilizing a human test subject with implanted muscular electrodes in their Residual Limb (RL). Consequently, this creates problems and delays in the testing phase of the control systems, inconveniencing all parties involved. The aim of this thesis is to develop a test system for an Artificial Limb Controller (ALC) designed by a Swedish medical device company called Integrum AB. Specifically targeting their model for transhumeral (TH) amputations (above the elbow) called ALC-TH. The ALC Test System is a combination of a Test Rig, a Test Device, and Test Software. It facilitates realistic testing of the ALC without relying on human test subjects by utilizing recorded EMG data from amputees. Moreover, it allows for testing of the ALC with an artificial arm attached in various positions by incorporating a lockable joint with a range of motion of 125° within the Test Rig. The Test System exhibits modularity, enabling convenient replacement of components in the event of issues or for future implementation and expansion purposes. Initial assumptions were made to acquire conservative minimum tolerances for the component selections of the Test Rig. Thorough investigations led to the component selections for each part of the Test System. Simulations were performed for assessing the maximum stress and safety factor of the final Test Rig design. The functionality of each Test Device component was individually tested using electrical equipment.Comprehensive integration testing was conducted to assess the performance of the Test System. Evaluation of the Test Rig’s mechanical strength was carried out by applying a conservative load, and a demonstration of the functionality of the Test System with the ALC and an AL was performed. These testing procedures confirmed that all components of the Test System operated as intended and met the desired functionality criteria to enable realistic testing of the ALC.