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This work presents preliminary experiments using a new hybrid vibro-electrotactile interface named HyVE. It integrates vibrotactile with electrotactile stimulation over the same physical location, and it is thus able to provide a dual-modality sensory feedback on the body site where it is applied. Since HyVE was envisioned as a feedback system for prosthetic limbs, as a first step, we investigated the capability of human subjects to discriminate the properties of the two stimulation types when they are delivered simultaneously. Preliminary results are very promising: nine subjects were able to discriminate 9 stimuli (combinations of 3 electro- and 3 vibro-tactile stimuli) with a mean success rate of 70 %. These results suggest that a hybrid interface can be used to implement two parallel information channels in a compact way. This could be exploited for the closed loop control of an upper limb prosthesis.

Adaptive Modular Active Leg (AMAL), a robotic Intelligent Prosthetic Limb has been developed at the Indian Institute of Information Technology Allahabad. The aim of the project was to provide the comfort of an intelligent prosthetic knee joint for differently abeled person with one leg amputated above the knee. AMAL provides him with the necessary shock absorption and a suitable bending of the knee joint oscillation. The bending and the shock absorption are provided by artificial muscles. In our case, it is the MR (Magneto Rheological) damper which controls the knee movement of an amputee. The feedback signal is provided by the heel’s strike sensor. AMAL has been kept simple with minimal feedback sensors and controls so that the product is economically viable for the patients. In this paper we describe the mechanical design, the electronic control with its successful testing on differently abeled persons.

Advanced dexterous prosthetics technology has been under rapid development as a potential solution to upper limb amputation. An important problem in the neural prosthetics design is to develop control policies for prosthesis movements. This requires an estimation of cognitive states. Previous works mostly used premotor and primary motor neurons to estimate cognitive states. Here we demonstrate that the recorded neural activity from the somatosensory cortex can be used to estimate cognitive states in complex behavioral tasks. We measure the latencies between the predicted cognitive state transitions and true transitions. The maximum prediction latency for grasping a sphere, pulling a mallet, pushing a button and pulling a cylinder are 42±21 ms, 91.6±10.7 ms, 177.1±94.6 ms, 22.5±74.5 ms, respectively. These latency estimates indicate that good timing of the cognitive states with small latencies can be obtained from the somatosensory neural data to plan movements of prosthetic limbs.

During upper-limb prosthesis use, proprioception is not available so visual cues are used to identify the location of the artificial limb. We investigate the efficacy of a skin stretch device for artificially relaying proprioception during a spring discrimination task, with the goal of enabling the task to be achieved in the absence of vision. In this study, intact users perceive the location of a virtual prosthetic limb using each of four sensory conditions: Vision, Proprioception, Skin Stretch, and Skin Stretch with Vision. For the conditions with skin stretch, a haptic device stretches the forearm skin by an amount proportional to the angular rotation of a virtual prosthetic limb. Sensory condition was not found to significantly influence task performance, exploration methods, or perceived usefulness. We conclude that, in the absence of vision, artificial skin stretch could be used by prosthesis wearers to obtain position/motion information and identify the behavior of a spring.

The design of a novel linkage three-phalanx finger was proposed in this paper. The finger is based on the concept of COSA (coupling and self-adaptation) and also two-phalanx COSA finger. As a combination of rigid coupled finger and self-adaptive under-actuated finger, the COSA finger has comprehensive grasping ability with human-like motion. Available topology designs were discussed in this paper and then mechanical design in details is given. Motion and grasping patterns of the finger were illustrated and compared with traditional coupled finger and under-actuated finger. Moreover, stability of grasp was simulated by static analysis. The three-phalanx finger with advantages of coupling and self-adaptation can be widely applied in hands for prosthetic limbs or humanoid robots.

Real-time pattern classification of electromyogram (EMG) signals is significant and useful for developing prosthetic limbs. However, the existing approaches are not practical enough because of several limitations in their usage, such as the large amount of data required to train the classifier. Here, we introduce a method employing a selective desensitization neural network (SDNN) to solve this problem. The proposed approach can train the EMG classifier to perform various hand movements by using a few data samples, which provides a highly practical method for real-time EMG pattern classification.

This chapter traces the development of myoelectric control of prosthetic arms from its conception in post-war Germany through its popular acclaim in “bionic arms” toward its acceptance as a routine and valid option for many arm amputees. Separate and apparently unrelated conceptions of myoelectric control in Germany, the United Kingdom, the USSR, the USA and Canada are followed with particular attention to the gradual achievement of collaborative ties research and the even slower development of commercial products for clinical application.The impact of wars, epidemics and world political climate upon this activity is noted. The chapter is written from the perspective of one of the authors (RNS), who directed a program of myoelectric controls research at the Institute of Biomedical Engineering at the University of New Brunswick, Fredericton, NB, Canada through this period and is based on a careful review of the extensive collection of relevant literature held at the Institute, much of which is unpublished or has had only a very restricted circulation.