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This research addresses attention to human upper limb experimental analysis during feeding process aiding disabled persons. The research core is focused on the experimental process of obtaining the angular amplitudes and trajectories developed by the human upper arm during feeding process. The research originality consists on the obtained results which can be used in further researches for command and control of robotic assisting devices.

This paper presents the methodology of designing a transducer for the experimental measurement of forces. For this purpose, an elastic element of the shape of the letter "S" is designed and manufactured. The elastic element designed in SolidWorks is subjected to virtual testing, using the finite element method in ANSYS. After validating the results obtained considering the maximum values ​​of the stresses that appear for the nominal load, the experimental model of the transducer is realized. The central part of the elastic element behaves like a fixed double beam subjected to bend by the measuring force. On this beam are bonded strain gauge transducers, which measure the deformations produced by bending. The transducer is calibrated, in order to obtain the calibration constant, based on the obtained characteristic, that is, the dependence of the specific strain-deformation and force. The transducer thus constructed can be used in force measurement applications.

This paper addresses to a research of a dynamic answer obtained through numerical simulations of a human ankle joint implant with finite element method. The research background consists of an inverse dynamic analysis based on Newton-Euler formalism completed with Lagrange’s multipliers method. Thus, a parameterized virtual model of a human ankle joint was elaborated and simulated together with the implant, in dynamic conditions similar with real ones in reality. A results numerical processing was obtained with the aid of MSC Nastran and important results were obtained for orthopedic implants design.

This research addresses to a method for 3D modeling of human bone structures. Human bones are characterized by a high level of geometrical complexity, thus the research objective is to obtain virtual bony models for analyzing them with proper engineering software. The proposed method is a derivative from a Marching Cubes algorithm and combines classical procedures with modern 3D modeling techniques and software. Through this method it is presented, as an example, the human lower limb 3D bony models developed mostly with CATIA software.

In this paper, we present a new robot model designed to assist human locomotion. The kinematic structure of the robot is presented, and the equations that characterize the movement of the robot are written. Based on this kinematic structure, the robot is modeled in the CAD design environment, SolidWorks, and the motion simulation is performed in the MSC.ADAMS simulation environment. The graphs of variation of the kinematic and dynamic parameters of the robot are analyzed. Based on the analysis of the designed robot's motion, conclusions are drawn regarding the usefulness of the modeled robot.

This paper presents studies concerning the design of exoskeletons for human lower limb motion assistance. A study concerning the structural and mechanical design in Solid Works is presented on the first part of the paper. In the second part, a human gait motion analysis with goniometer sensors is performed. Also, a kinematic characterization for the new proposed leg exoskeleton is performed. The exoskeleton achieved design is based on a seven-link mechanism, designed to accomplish requirements of human locomotion. The kinematic computational model and the obtained results with plots in ADAMS software are presented. The obtained simulation results are compared with experimental human gait, and they are useful to characterize the exoskeleton motion and to demonstrate suitable performance for human rehabilitation purposes.

This paper addresses a knee orthotic system design used on a 4-year-old child with locomotion problems. This knee orthotic system design was made by performing a dynamic analysis of the proposed child locomotion system. The aim of this dynamic analysis was to obtain knee joint connection forces in case of a walking activity. For the proposed dynamic model, input data such as hip, knee and ankle joint motion laws were considered. These were obtained through an experimental analysis with a high-speed video camera equipment on a healthy child. Thus, a database was created, which was used as input data for numerical simulations made in a dynamic mode with MSC Adams. Through these numerical simulations, important results were obtained, and these will further validate the proposed prototype.

In this research an experimental test rig and method to measure friction torque from screw-nut assemblies is presented. The experimental test rig uses to measure friction torque an elastic cylinder bush with strain gauge transducers. The frictions torque and the traction force from the threaded assembly are transmitted to the elastic cylinder bush and produce elastic deformations. The elastic cylinder is calibrated in order to establish a correlation between elastic deformation and force of solicitation. In order to measure the experimental data the MGCPlus data acquisition system is used. The experimental results obtained are presented, consisting in the dependence between friction torques and axial traction force occurred in the screw.

This research addresses a human ankle joint prosthesis design based on a cam mechanism. Thus, a dynamic analysis of the entire human lower limb was performed in order to obtain the input data for numerical simulations of an ankle joint prosthesis. For this, experimental analysis was accomplished in order to obtain input and reference data for human ankle joint motion laws. These human ankle joint motion laws were considered from a healthy human subject and an amputee. A virtual model of the ankle joint prosthesis was designed with the aid of CATIA software and the working principle was based on a cam mechanism. This virtual model was simulated in dynamic conditions, similar to the imposed ones onto a mathematical model. Results represented through stress and deformations will validate the proposed ankle prosthesis prototype. Finally the proposed prosthesis prototype was manufactured and experimentally tested on the proposed amputee through a comparative analysis for validation.

In this paper an experimental research was performed in case of a human rehabilitation exoskeleton. The research aim was to evaluate the joint trajectories and the influence of the ground-foot contact by using two distinctive shapes of the exoskeleton foot. Thus an experimental motion analysis was used, called CONTEMPLAS and an exoskeleton prototype with 1DOF placed on a treadmill. The experimental activity was developed when the exoskeleton was used on walking activity. There were studied two types of foot shapes and also the generated impact of their form on the hip, knee and ankle joints trajectories during walking. The obtained results will be useful for the improvement of the exoskeleton orientation in space.

In this paper we aim to experimentally determine the bearing capacity (the momentum) of the elastic bracelet assemblies. The moment of torsion transmitted by the assembly depends on the clamping force of the assembly and on the friction coefficient between the bushing mounted on the shaft and the hub of the assembly. An experimental stand is used which comprises a hub shaft assembly with a segmented elastic bracelet. The load bearing capacity of the elastic bracelet is determined depending on the strength of the screws. Experimental determination is made on three types of materials. For this purpose, on the shaft is assembled a bush made of different materials: aluminum, bronze, steel. In order to determine the capable assembly moment, strain gauge transducers are used to measure the elastic strains. The recording of the deformations is done by means of an efficient data acquisition system. The assembly characteristic is plotted, namely the dependence between the torque transmitted according to the tightening of the bolts, for three couples of materials.

In this paper a locomotion system kinematic analysis is presented in order to obtain the hips, knees and ankles motions equations for a child walking. With these equations an experimental test bed was especially designed and simulated for locomotion rehabilitation by using MSC Adams. The whole human locomotion system was analyzed from kinematic viewpoints. Based on the obtained results a locomotion rehabilitation test bed prototype for a 7 years old child with locomotion disabilities was fabricated.

In this paper it is presented the theoretical, experimental and numerical simulation of critical speed for right shafts. For this purpose, it is designed a virtual model of a test bench for shaft critical speed analysis. The studied shaft is mounted on two bearings and on the middle it has mounted a heavy disc. The system has the possibility to modify the shaft speed with a frontal friction continuous variable transmission. It is presented a mathematical model to calculate the critical speed of the shaft. The result obtained by analytical calculation is verified by experimental way and by numerical simulation. The simulation of shaft flexibility is achieved in ADAMS multibody software and obtained results are presented and discussed. Shaft experimental flexional deformations and the results obtained by numerical simulation are similar. Study of shaft flexibility by numerical simulation in ADAMS is an easy tool and very important for practical application to avoid resonance in elastic mechanical systems.

In this paper is presented the design solution and experimental prototype of a wheelchair for disabled people. Design solution proposed to be implemented uses two reduction gears motors and a mechanical transmission with chains. It’s developed a motion controller based on a PWM technology, which allows the user to control the wheelchair motion. The wheelchair has the ability of forward – backward motion and steering. The design solution is developed in Solid Works, and it’s implemented to a wheelchair prototype model. Wheelchair design and motion makes him suitable especially for indoor use. It is made a study of the wheelchair kinematics, first using a kinematic simulation in Adams. Are presented the wheelchair motion trajectory and kinematics parameters. The experimental prototype is tested with a motion analysis system based on ultra high speed video cameras recording. The obtained results from simulation and experimentally tests, demonstrate the efficiency of wheelchair proposed solution.

In this paper are presented the author’s researches on designing, dynamical and structural evaluation of a transmission for a wheelchair, intended to persons with locomotors disabilities. The kinematics of proposed transmission is analyzed in order to realize a proper synthesis and design of gears. A 3D model of the transmission and wheelchair are designed in Solid Works, and they will be used for the dynamic simulation of the wheelchair robotic system in Adams software. In Adams is analyzed wheelchair trajectory and dynamics for a combined trajectory: linear motion and steering. Dynamic parameters obtained from simulation are used to perform a finite element analysis of bevel and worm gears. Simulation results reveal the transmission dynamics parameters, emphasize the efficiency of the transmission and enable implementation of this design to a wheelchair model.

Legs are the mostimportant elements for accomplishing human physical work includingtransportation or displacement. In this paper, a new mechanism for human legmotion assistance has been proposed for rehabilitation purposes. The structureof human leg and its motions have been used as inspiration for design purposes.For a simple control algorithm, the proposed mechanism for the legs mustgenerate an ovoid path of the foot, by uniform rotating of actuating crank. Themechanism must generate an approximately linear trajectory of foot duringpropulsion. The resulting linkage is a single degree-of-freedom (DOF)mechanism, which exemplifies the shape and movement of a human leg. Theactuator of the mechanism is located in the upper portion of the linkagesimilar to it in a human leg. The mechanism is simulated and tested to verifythe proposed synthesis. A 3D model of the proposed system has been elaboratedin Solid Works®, booth for design and simulation purposes. Simulation resultsshow that the proposed mechanism performs movements similar to those of a humanleg. Maple and Adams software packages are used to simulate and validate the usabilityof the mechanism. The proposed mechanism demonstrates that a one DOF closedloop mechanical linkage can be designed to the shape and movement of the bipedhuman walking apparatus. The proposed mechanism is suitable for the fabricationof legged robots. Proportions of the linkage are estimated utilizinganthropometric measures of the human leg.

In this paper is carried out the selection and simulation of a one degrees of freedom (DOF) leg mechanism. The leg mechanism consist of a nine bar linkage and is based on a Low-cost Easy-operation idea. Virtual simulation tests of the model shows the feasible of the proposed leg mechanism, for human leg motion assistance. Kinematics and dynamics analysis of the leg mechanism is carried out. Finally, dynamic simulation results reveal the motion characteristics and performance of the leg mechanism.

In this paper, a method is described for theoretical and experimental studies of a front and rear stabilizer bars used on vehicle steering and suspension systems. Based on the fatigue experimental tests performed on a special test-bed, a complex actuation mechanism from the test bed structure will be analyzed. This mechanism through his kinematic and dynamic structure assures complete conditions for simulating the dynamic behavior in a complex mode of the rear stabilizer bar used on a vehicle steering and suspension structures.

The paper illustrates the structure of plane mechanical systems used to manipulators. In the first part are presented some kinematics schemes used to plane manipulators. These mechanisms are used to manipulators, positioning and control systems. In generally these mechanisms have two or three degree of mobility. The purpose of the paper is to study the dynamics of a plane manipulator mechanical system used to manipulate garbage containers. It is presented the kinematics scheme of a plane manipulator, used to this purpose and is presented the mechanism functional description. In the second part is presented the kinematical and dynamical analysis for the plane manipulator mechanism. In the last part of the paper are presented graphical results for the dynamics parameters.

The paper is structured in two parts. In the first part are presented some kinematics schemes used to the positioning and control systems, from the harvester machine structure, hydraulic excavators. In generally these mechanisms have two or three degree of mobility. It is presented those mechanism structures upon the base module. In the second part is presented the 3D model and the kinematical analysis results for one plane excavator mechanism, with the help of MSC.Adams computer program.

In this paper is presented the design and an experimental prototype of a wheelchair for disabled people. Design solution proposed to be implemented uses two reduction gears motors and a mechanical transmission with chains. The motion controller developed uses PWM technology (pulse wave modulation). The wheelchair has the ability of forward – backward motion and steering. The design solution is developed in Solid Works, and it’s implemented in a wheelchair prototype model. Wheelchair design and motion makes him suitable especially for indoor use. It is made a study of the wheelchair kinematics, first using a kinematic simulation in Adams. Are presented the wheelchair motion trajectory and kinematics parameters. The experimental prototype is tested with a motion analysis system based on ultra high-speed video recording. The obtained results from simulation and experimentally tests, demonstrate the efficiency of wheelchair proposed solution.

This paper addresses attention to the conceptual mechanism design of a leg exoskeleton for human rehabilitation purposes. Different mechanism solutions for locomotion rehabilitation are analyzed from a structural and functional viewpoints. By using mobility analysis and considerations on structure design, a new leg exoskeleton is identified with low-cost features and motion ability for rehabilitation purposes.

In this paper we present the kinematics model of a biomechanism which represent the legs of a four legged mammal. The anterior and posterior legs are realized as plane mechanisms, with articulated bars. Each anterior leg has a complex structure with three closed contours, mean while each posterior leg has only two closed contours. Each mechanism is actuated by an electric motor. The geometric and kinematics modelling of the anterior leg mechanism is achieved by means of some vectorial and scalar equations. Also, the kinematics simulation is achieved by means of Msc.Adams software, considering as basis, the upper platform of each mechanism.

In this paper a locomotion system kinematic analysis is presented in order to obtain the knee motion equations for a child walking. With these equations a modular knee orthosis with flexible elements was designed and simulated through finite elements analysis with ADAMS. The whole human locomotion system is analyzed. Based on these results a modular knee orthosis prototype for a 7 years old child with locomotion disabilities was fabricated. The prototype was evaluated through experimental tests with CONTEMPLAS motion analysis equipment.