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Foot movement during walking, jogging, running, jumping, skidding, and climbing etc. is an important emphasis in lower limb prosthesis. This work presents the estimation of gait phases of walking persons on flat terrain. Different phases of swing and stance of foot gait cycle have been considered with sensing unit consisting of gyroscope and potentiometer. Arduino microcontroller has been incorporated to process the values received from the sensing unit using rule based algorithm. Sensor values are processed using ‘Extra Putty’ software and the results are observed at serial monitor. This project has been tested on a person and real time gait phases have been drawn. Gait phases of forward and reverse walk have been successfully identified. The work is useful to identify the balanced/unbalanced state of persons during normal walk.

This paper presents the design of a stair climbing fixed flipper unmanned ground vehicle (UGV) for urban search and rescue purposes. Mobile flippers are being used in certain UGVs for enhanced mobility in rough terrains, however, the control algorithm of these platforms is complex. To add this enhanced mobility in the UGV and to reduce the intricacy of the control algorithm, anterior end of the tracks are lifted up which enables the UGV to pass over obstacles with relative ease. To prevent the rollover of UGV while moving on an inclined surface, an image processing algorithm was developed which halts the motion of UGV if the calculated slope exceeds the threshold value with a maximum error of about 8%. Furthermore, left and right track velocities along with the turn radius were also calculated.

Transtibial amputation may be caused by a disease or an accident. The rehabilitation for this type of amputation is to replace the amputated part by a prosthetic limb. Most of the commercially available DER (Dynamic Energy return) prosthetic feet contain soft components, that store and release energy. In contrast, the proposed model of prosthetic foot stores and release energy by means of material properties and geometry. Traditionally, the performance analysis of prosthetic feet required the existence of prototype. However, latest numerical techniques allow analysis, during the design stage. ISO-22675 has proposed experimental setup and standard for the analysis of any prosthetic foot. In this work, instead of using experimental setup and physical prototype, the proposed foot has been modeled, analyzed, and optimized using FEM (finite element method) as per the boundary conditions specified by ISO-22675, during the design process. The aim of his paper is to develop a low-cost, fixed prosthetic lower limb, DER foot, that is within the buying power of lower income class and its performance and features are as per ISO standards. The foot has been designed using displacement and stiffness parameters of Niagara FootTM and analyzed as per ISO Protocol 22675 using FEM analysis.

This paper presents design, simulation and fabrication of a surface electromyographic (SEMG) sensor for control of prosthetic devices. EMG activity is mainly the generation of a bio-potential signal (electrical signals) due to muscle action. These signals picked from motor points of muscles are contaminated with various intrinsic/extrinsic noises, which must be removed through different filtering techniques in order to develop a sensor that has a high signal-to-noise ratio. Power spectral density (PSD) of any EMG signal plays a vital role to determine the signal strength. A novel Simulink model has been developed which mimics various elements of an active SEMG sensor. By using this model, low/high/notch filters are designed and optimized. The model is also used to simulate the effects of these filters on power spectral density (PSD) of the EMG signal. Simulation of double rectification and smoothing (envelopment) is also carried out. EMG signals recorded from the Tibialis anterior, monopolar needle, and fine wire isometric contraction were used in this simulation. Finally, on the basis of simulation results, instrumentation of surface EMG sensor is designed and fabricated. Performance/results of developed SEMG sensor are in accordance with the simulation results of the developed Simulink model.

Below-knee amputation is one of the most critical types of amputations related to gait disability. A very effective therapy is to replace the amputated part by a robotic prosthetic lower limb. This limb consists of different design parameters with most important and crucial being its actuator. Since the power transmission to the foot and movement control is directed through the actuator, it is very important to use an actuator which fulfills all the vital parameters required for the prosthesis to work effectively i.e. weight, torque and speed. Conventional actuators available on the market do not control all these parameters. The purpose of this paper is the development of an effective actuator design, for assisting robotic prostheses that can be used by amputated people in the everyday environment to obtain natural gait. The presented design has been validated using finite element analysis (FEA).

This paper discusses the development of a customizable FPGA based system for implementing control algorithms on an Unmanned Ground Vehicle (UGV) and its 5 Degree of Freedom (DOF) manipulator. The compact RIO-9012 is used as a controller which is a reconfigurable embedded control and acquisition system using LabVIEW as the programming platform. The developed system enables the control of UGV and its manipulator using a remote joystick controller via Wi-Fi communication. Apart from Joystick, the system can also be controlled optionally using a keyboard. Accuracy of Joystick control has been enhanced by using point to point mapping technique. A user friendly GUI has been developed to view live video feedback obtained from the onboard cameras to control the UGV accordingly. Different features of UGV like path tracker (tracks its path on Google Maps), variable speed modes, battery indicator, camera switch and selector etc. are also managed in the GUI. The system has been developed so that, in future, it can easily be extended to a fully autonomous system.

A type of unmanned ground vehicle (UGV) called Versatile Terrain Mobility Platform (VTAMP) has been designed with the idea of providing a dynamic mobile platform with the unique ability of traversing through rough terrains, and also to pass over obstacles otherwise proving to be a difficult task for most tele-operated ground vehicles. Increased maneuverability is achieved by using active arm-like tracks called “ flippers”. By being able to operate each flipper independently, we can operate VTAMP in different modes with the operator control unit (OCU) which in our scenario is a laptop. This is achieved through feedback loop on each flipper using encoders. The ability to c hange configuration facilitates VTAMP to be able to adapt to all kinds of terrains. The basic architecture of VTAMP is presented first, followed by its different modes of operation by possible flipper arrangements and its control scheme. An algorithm was made to prevent accidental collision between flippers. In addition to this, the turning radius of the VTAMP was also calculated according to the track speeds of both sides which were then verified through experiment.

In recent times there is a prevalence in amputations in the developing world due to lack of proper medical treatment of diseases & injuries sustained in natural disasters or war; creating a need for an optimal solution that is technically sound and is affordable. This paper discusses the available solutions in the market and then proposes a new design for prosthetic hands, incorporating the morphological features of the actual human hand. Each finger, actuated by a slider mechanism, has a single degree of freedom. While the thumb design utilizes worm gear driven mechanisms to feature a double degree of freedom. The morphology of the developed device is that of the adult male human right hand. The motors for actuation are installed inside the palm of the hand while the overall weight of the prosthetic device is 453 g. The control is generated by the forward kinematics model assessing the relation between the slider position and the rotation angles of the metacarpophalangeal (MCP) joints of the individual fingers. A feedback control loop provides the adaptive grip. The developed prosthesis design can be used to interface with either an EMG or EEG-based control scheme.

This paper presents our approach to staircase detection and perception using monoscopic vision. The simulation of the proposed algorithm is conducted on a 4 degree of freedom teleoperated vehicle. The presented solution can detect a staircase and calculate its angle of inclination thus aiding the operator in setting up controls for the vehicle. The approach relies on multiple 5×5 masks to actively predict staircase from the front then by a combination of blob detecting algorithms predict the angle of inclination. One of the challenges was to make the algorithm efficient so that it can be implemented on low power embedded systems. Results of simulations on various acquired images have been discussed within the contents of the paper. The results have been validated by monitoring values over multiple & different staircases. MATLAB's image processing toolbox has been used to conduct simulations of the algorithm.