Development of a VR/3D Hand Prosthesis Software Application: Avatar Customization and Hand Motion Control

Abstract

Abstract When a titanium device was first implanted into a thumb in Sweden in 1990, the osseointegration program for upper extremity amputation had its start there. Since then, below-elbow and transhumeral amputations have been performed using this technique. The e-OPRA system is an advanced version of a technique called the OPRA Implant System which is a technology in which it is possible to attach an artificial limb to the skeleton directly. It enables the acquisition of bioelectrical signals through implanted electrodes and nerve stimulation. The Artificial Limb Controller (ALC) System acts as a non-implanted device, facilitating communication between the e-OPRA system and a third-party robotic prosthetic for the upper limb. The e-OPRA/ALC system has software that is used for fitting, which is the process modifying and personalising the system’s software to meet the recipient’s unique needs and preferences. It includes setting up the software in order to make sure the recipient’s prosthetic equipment is compatible with it. It involves configuring the software and ensuring its compatibility with the recipient’s prosthetic device. It also has the potential to replicate movements for training and phantom limb reduction. Tools and software are used for configuring and maintaining the ALC system and eOPRA implant system. The aim of the project is to explore and showcase the various functions and platforms that can be utilized to create and present interactive 3D models for software application. The project involves creating a human avatar that accurately represents behavior of hand movements, visual appearance, animation, and movement interaction. It is mainly focused on platform and tools investigation as a pre-study. Additionally, it aims to develop a software unit to enhance the control and interaction capabilities of prosthetic devices through virtual reality (VR) training. Furthermore, the model will be exported to different platforms to ensure compatibility with the existing software and hardware in the market. The main objective of the software unit was to provide various upper limb movement control options, elbow flexion and extension, wrist supination and pronation, and hand opening and closing. Users could manipulate virtual items accurately and independently control each hand, enhancing the authenticity of hand movements. Additionally, a mouse-based control option was implemented to improve precision and ease of movement for delicate interactions or complex hand gestures. Although user feedback was not collected through surveys or interviews, valuable information was obtained from the comprehensive evaluation through the testing of the prototype in different conditions, which highlighted areas for improvement. Areas for improvement in a future fitting application were identified, including di versifying training scenarios, enhancing the user interface, optimizing performance, and expanding platform compatibility. Future research and development suggestions involved incorporating electromyography (EMG) technology for dynamic control, vimproving usability and user experience. However, limitations should be considered, such as technical constraints and the potential disparity between virtual limb realism and real-life counterparts. The effectiveness of virtual limb visualization in reducing phantom limb pain may vary among individuals. Compatibility issues when exporting models to different platforms and the need for clinical validation should be considered. These limitations impact the interpretation and practical application of the project’s outcomes. In conclusion, the developed software unit has the potential to significantly enhance the training experience for individuals with prosthetic limbs. Through further research and development, incorporating user feedback and advancing technologies, the field of prosthetics can continue to evolve, providing amputees with improved mobility and quality of life.