Raisuddin Khan

State of the art review on walking support system for visually impaired people

The technology for terrain detection and walking support system for blind people has rapidly been improved the last couple of decades but to assist visually impaired people may have started long ago. Currently, a variety of portable or wearable navigation system is available in the market to help the blind for navigating their way in his local or remote area. The focused category in this work can be subgroups as electronic travel aids (ETAs), electronic orientation aids (EOAs) and position locator devices (PLDs). However, we will focus mainly on electronic travel aids (ETAs). This paper presents a comparative survey among the various portable or wearable walking support systems as well as informative description (a subcategory of ETAs or early stages of ETAs) with its working principal advantages and disadvantages so that the researchers can easily get the current stage of assisting blind technology along with the requirement for optimising the design of walking support system for its users.

Design and data analysis for a belt-for-blind for visual impaired people

This research designs a new walking support system for the blind people in order to navigate without any assistance from others or using any guide cane. With the help of this device, a user can move independently and able to walk freely almost like a normal person. In this research, a belt for blind wearable around the waist is equipped with four ultrasonic sensors and one sharp infrared sensor. A mathematical model has been developed based on the specifications of the ultrasonic sensors to identify optimum orientation of the sensors for detecting stairs and holes. These sensors are connected to a microcontroller along with a laptop so that we can get sufficient data for analysing terrain on the walkway of the blind. Based on the analyses of the acquired data, we have developed an algorithm capable of classifying various types of obstacles. The developed belt for blind device is superior in terms of less weight less, able to detect stair and hole, low cost, less power consumption, adjustable, less training and availability of actuation systems. It was tested and implemented successfully to address all those issues.

Electroactive polymer actuated tendon driven micro actuator for robotic application

Tendon driven actuators are getting mature in electroactive polymer (EAP) researches. Research and development of the dielectric elastomer (DE) actuator from EAP family, have produced significant progress for decades. Dielectric elastomer is used in this paper to model a micro actuator platform. The parallel platform designing in this paper consists of the kinematics of the platform that is suited for micro structure of the robotic link. This may use for redundant manipulator or snake robot structure. DE is silicon artificial muscles that will actuated by applying voltage which perform a great actuation due to its linear large deflection. A remarkable amount of work has focused on delivering the feasibility of the robotic application of DE material. However, few commercial products equipped with polymer actuators have been introduced in the market, probably because most of the research has been dedicated either to discovering new actuation properties of the polymeric material. Therefore, this polymer is used to model the tendon driven parallel platform actuator for robotic application in this research. In this actuator design, both the upper and lower platforms are of configurations of equilateral triangles with DE cables attached close to the vertices. One DE cable attaches each of the vertices of the lower platform to the vertices directly above it on the upper platform. The three tendons thus enable the platform to exhibit 3 degrees of freedom (DOF). The dielectric polymers are attached with the three edges of the platforms that act like compression-tension cable because of their linear deformation characteristics. Therefore the platform of the DE actuator model is achieved in this research. This actuator can be used to develop redundant robot like snake robot or elephant trunk robot.

Nonlinear modeling of compliant mechanism

In this paper, feasibility of using pseudo-rigid-body modeling technique in examined on a simple modular compliant mechanism. A mathematical model is constructed to determine the non-linear behavior of large-deflections. The problem is solved using an iterative method. The solution to the non-linear model is then compared to empirical results collected from a mock-up of the compliant device. The pseudo-rigid-body model is then combined with a linear model to develop the complete solution, which shows behavior fairly close to the actual behavior of the mock-up.

Design of a profilograph for mapping pavement in virtual environment

In this paper, a novel profilograph has been designed and implemented to generate virtual terrain. Profilograph is necessary for civil engineering applications to map pavement smoothness. Traditional profilographs are big in size and take long time for mapping, although they are capable of generating pavement map but unable to show 3D graph. The profilograph proposed in this paper is able to map pavement smoothness faster as well as show 3D graphs of the pavement. This profilograph consists of two subsystems. The first subsystem is a hardware system designed using rate gyros and accelerometers with some wireless communicating module. Another subsystem is the software system developed using OpenGL with supported of C++ and Visual Basic. This software can be connected with the hardware system either using wire or using wireless. The hardware system while driven on the pavement stores the data of the terrain into the database. The software generates 3D graphs of the navigated terrain. This profilograph can be used not only in civil engineering pavement mapping but also in mapping disaster scenario for disaster rescue missions.

A new geometrical approach to solve inverse kinematics of hyper redundant robots with variable link length

In this paper a new approach that generates a general algorithm for n-link hyper-redundant robot is presented. This method uses repetitively the basic inverse kinematics solution of a 2-link robot on some virtual links, where the virtual links are defined following some geometric proposition. Thus, it eliminates the mathematical complexity in computing inverse kinematics solution of n-link hyper redundant robot. Further, this approach can handle planar manipulator with variable links eliminating singularity. Numerical simulations for planar hyper redundant models are presented in order to illustrate the competency of the model.

Prediction of dry ice mass for firefighting robot actuation

The limitation in the performance of electric actuated firefighting robots in high- temperature fire environment has led to research on the alternative propulsion system for the mobility of firefighting robots in such environment. Capitalizing on the limitations of these electric actuators we suggested a gas-actua ted propulsion system in our earlier study. The propulsion system is made up of a pneumatic motor as the actuator (for the robot) and carbon dioxide gas (self-generated from dry ice) as the power source. To satisfy the consumption requirement (9cfm) of the motor for efficient actuation of the robot in the fire environment, the volume of carbon dioxide gas, as well as the corresponding mass of the dry ice that will produce the required volume for powering and actuation of the robot, must be determined . This article, therefore, presents the computation al analysis to predict the volumetric requirement and the dry ice mass sufficient to power a carbon dioxide gas propelled autonomous firefighting robot in a high-temperature environment. The governing equation of the sublimation of dry ice to carbon dioxide is established. An operating time of 2105.53 s and operating pressure rang es from 137.9kPa to 482.65kPa were achieved following the consumption rate of the motor. Thus, 8.85m 3 is computed as the volume requirement of the CAFFR while the corresponding dry ice mass for the CAFFR actuation ranges from 21.67kg to 75.83 kg depending on the operating pressure .

Characteristics of Human Arm Impedances: A Study on Daily Movement

This paper presents the impedance characteristics of human arm in daily spatial activity. Human arm is considered as a mass-spring-damper system. The input data in the form of Cartesian position is measured to get dynamic impedance relationship by the motion equation for the mass-spring-damper system. Mappings are done by various combinations to observe the nature of the different impedance components during dynamic movement. The significant amount of variation in damping and inertia components are observed in every turning of the arm movement while the stiffness shows the changing behavior throughout the movement. From this study it is known that for this particular movement the arm follows a pattern and same behavior is followed for the repetitions of the movement. The obtained result could be beneficial for the study of upper extremity exoskeleton for human rehabilitation.

Investigation of Annular Gap Size for Optimizing the Dynamic Range of MR Damper Using Comsol Multiphysics Software

Magneto-rheological (MR) fluid technology has made it possible to develop reliable, revolutionary vibration control systems for a variety of commercial, medical and military applications. MR fluid shock absorber systems are enabled by remarkably versatile MR fluid technology, which allows the system to respond instantly and controllably to varying levels of vibration or shock with simple, robust designs. This paper presents a parametric study of the MR dampers for semi-active vibration control. The influence of gap size of the damper on the viscous stress of the MR fluid is examined. It is inferred from the study that the viscous stress of the MR fluid for different parameters such as gap size influences the dynamic range of MR fluid dampers.The simulated results depict a maximum viscous stress of 1765.441 N/m2for a gap size of 1.85 mm. The developed dynamic range would allow for smaller size of the device, higher dynamic yield stress and low power consumption. The simulated results using COMSOL multiphysics for the verification of the parametric strategy have been presented. Results of this study shall enhance the design of MR dampers for different control applications.

Development of a Novel Locomotion Algorithm for Snake Robot

A novel algorithm for snake robot locomotion is developed and analyzed in this paper. Serpentine is one of the renowned locomotion for snake robot in disaster recovery mission to overcome narrow space navigation. Several locomotion for snake navigation, such as concertina or rectilinear may be suitable for narrow spaces, but is highly inefficient if the same type of locomotion is used even in open spaces resulting friction reduction which make difficulties for snake movement. A novel locomotion algorithm has been proposed based on the modification of the multi-link snake robot, the modifications include alterations to the snake segments as well elements that mimic scales on the underside of the snake body. Snake robot can be able to navigate in the narrow space using this developed locomotion algorithm. The developed algorithm surmount the others locomotion limitation in narrow space navigation.