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A large work has been devoted to create and design the novel underactuated robotic hand that mimic human hand in terms of motion and grasps. The objective of this paper is to design and development of four-finger underactuated robotic hand mechanisms with 2-DOF for each finger that is highly underactuated which controlled by single actuator that can be used with wide applications. The principle of this hand mechanism is to use the linkage seesaw differentials and the design of robotic finger integrates segments by pin joints and a tendon, that allowing it easily of grasping and adaptable different objects. Furthermore, the robotic finger was designed with combines advantages of the concept of rigid coupled and selfadaptive into one unit to achieve better performance with simple design. To plan the trajectory of the robotic finger and force-isotropic that resembled the human finger in motion and grasping operation, Underactuated finger mechanism was preliminary analysis to predict the relationship between the joint angles of robotic finger related to mechanical parameters as well as contact forces then, modified by optimized set of parameters using particle swarm optimization (PSO). Where, the parameter design constraints were formulated for a multi objective optimization problem using the evaluation criteria for human finger in motion and grasping. Experiments were conducted in order to validate the theoretical analysis by addition of angles sensors on each segment of fingers and the results show that the proposed hand is able to mimic human hand in terms of motion and adaptive grasps.

The absence of a limb impacts devastatingly on any person, especially if it is the lower limb as it is paramount to human locomotion. The effect of mobility loss reduces independence, and affects amputees’ lifestyles. A smart prosthetic knee joint is designed and manufactured in which the amputee above the knee can perform various daily and effective movements. It is distinguished by its distinctive and very high efficiency mechanically and electronically. The new design of the artificial smart knee joint has proven to be 100% successful as a passive mechanical movement. Should a power failure occur at the source, the ability to move smoothly is very high, proved highly efficient by walking, sitting, and applying various daily movement activities. The artificial knee joint is able to detect the movement of the residual limb according to the results of the movement study, thus allowing the prosthesis to simulate the biomechanics of the missing limb without any difficulty by using the finite element method (FEM) as a numerical technique. The results showed that 94.303 MPa and 0.1379 mm are the highest stresses and displacements experienced by the knee joints, respectively at 110°. This remains below the yield stresses of 339.15 MPa (depending on the properties of aluminum alloy material 2024-T3). On the other hand, the highest safety of factors was at 0° with a value of 5.5905 and the lowest safety of factors was at 110° with a value of 3.5964. The above results show that von Mises stresses and displacement increase with increasing the angle of flexion of the knee joint while the safety of factors decreases as the angle of flexion of the knee joint increases. The result of finite element analysis shows that the concept is safe enough to use for this specific topic.

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In this paper a quarter-vehicle full-scale suspension test rig was designed and manufactured,the suspension is considered semi-active as the electrohydraulic (EH) damper used is fullycontrolled. This gives an indoor-based simulation tool which is important for vehicle testing;.This reduces the cost significantly with accurate results, especially when designing a newsuspension system. The aim of the current work was to build a new quarter-vehicle test rigwith expandable capabilities for diverse design objectives, also may be used for academicpurposes. The control objective was achieved by using dynamic characteristics of theelectrohydraulic (EH) damper to suppress the oscillation of the sprung mass due to roadirregularities. The test rig was constructed using a Genesis G80 (2016) suspension system.Finally, the simulation results demonstrated that the proposed controller used be able toefficiently regulate the chassis vertical oscillation under these irregularities. The experimentalresults for the quarter-car model showed good results between experimental and simulatedresults, where the proportion of conformity about 95%