This paper describes about the design method of "Rubber-Less Artificial Muscle". The contraction mechanism of the artificial muscle consists of behavior that the sleeve is expanded by the inflation of the air bag. So it is important to consider the relation between the size of the sleeve and air bag. In this design method, it is considered about volume ratio of the air bag and the sleeve. We produce the rubber-less artificial muscle by using this design method.

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The passive dynamic control ("PDC") is a new mechanical system control method based on an inherently safe design. It requires a brake device to keep the position until the safety is confirmed. In his note, the PDC is applied to pneumatic rubber artificial muscles, and a PDC cybernetic actuator with a dram brake is proposed. Positioning control and follow-up control to a sine curve are shown, and the effectiveness is examined through experiments.

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In recent times, robots have become familiar to human. The robot is requested to have safety systems when it contacts with human. Then, we propose using the rubber artificial muscle driven by air pressure for a robot's actuator. However, the flexibility of these artificial muscles make the manipulator generate vibration. Therefore we consider controlling this vibration by MR brake. In this paper, we build the pseudo-damperization of the MR brake. Moreover, we could control the viscosity coefficient of the evaluated elements of the manipulator and calculate the optimum brake torque as an indicator, and examined the effect.

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The purpose of our study is to develop a spherical pneumatic actuator as a flexible mechanism with a simple structure. This novel actuator will be applied to a rehabilitation device for human wrist. In this paper, a spherical pneumatic actuator using two flexible pneumatic cylinders is proposed and tested. This paper describes the construction, operating principle and fundamental characteristics of the tested spherical actuator. In addition, the master-slave control system using the tested actuator, a microcomputer, two accelerometers and four small-sized quasi-servo valves is constructed and tested. As a result, the tested actuator can work in a range of 240 degrees and can generate the torque of more than 0.3 Nm. It is also confirmed that the slave spherical actuator can track the master's movement by the use of quasi-servo valve which consists of two on/off control valves.

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Due to the ageing and the decreasing birth rate in Japanese society, an important problem of providing nursing care for the elderly has occurred. Therefore, it is strongly desired to develop a wearable actuator to use in nursing care or rehabilitation. The purpose of this study is to develop a high-power flexible actuator which can be used in supporting a bathing. In this paper, we proposed and tested a rubber artificial muscle with the inner diameter sensor which consisted of two photo reflectors. The position control was carried out using the actuator with the built-in inner diameter sensor and the quasi-servo valve. As a result, the axial-direction displacement of the actuator could be estimated well by the tested inner diameter sensor, and a good position control performance was obtained. The large-scale bending actuator using the actuator with the built-in inner diameter sensor was also tested and investigated.

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The purpose of this study is to develop a seated position assist device to control a seated position. The developed device is constructed with six layer type pneumatic actuators. The developed device can be operated by on expansion of the actuator. The layer type pneumatic actuator is composed of two nylon bands and an expansion unit, which is constructed with an aluminum film balloon and a nylon band. By measuring a height direction and an inner pressure, this actuator can estimate an applied force. The developed device can also estimate a gravity center by using the above estimated force. In this device, the seated position is controlled based on the estimated gravity center. In this paper, the structures of the layer type pneumatic actuator and the seated position assist device are described, and then the seated position control using the estimated gravity center is discussed.

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A conventional curved type pneumatic rubber artificial muscle is composed of an internal bladder covered with a bellows sleeve extending axially. By inhibiting the extension of one side with a fiber reinforcement, bending motion occurs when an air is supplied into the bladder. In this study, we developed a new actuator by replacing the fiber reinforcement with shape-memory polymers (SMPs). SMPs can be deformed above their glass transition temperature (T_g). They maintain their shape in a rigid form after they have been cooled below T_g. When next heated above T_g, they return to the initial shape. When only part of our actuator is wanned above T_g, only that portion of the SMP is soft and can actuate. Therefore, the direction of the motion can be controlled by heating. Moreover, our actuator can be deformed by an external force above T_g and fixed as its initial shape below T_g.

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This paper reports fundamental characteristics of Rubber-less artificial muscle. We also examined a rictional influence between outer sleeve and inner airbag. As a result of having compared a fundamental characteristic with Shadow artificial muscle, it was able to be confirmed that the Rubber-less artificial muscle is superior to Shadow artificial muscle in power and contraction ratio. In addition, Rubber-less artificial muscle has a small friction. Therefore, we confirmed that Rubber-less artificial muscle converts pressure into displacement and force with McKibben artificial muscle efficiently.

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Recently, research and development has focused on robots that work in place of people. It is necessary for robots to perform the same flexible motions as people. Additionally, such robots need to incorporate high-level safety features. Here, we present artificial muscle-type pneumatic actuators as the driving source of a robot hand that is both safe and flexible. We develop a low-pressure, low-volume pneumatic actuator for driving a robot hand. We develop a five-fingered robot hand with pneumatic actuators. Next, we make a 2-link arm that has two degrees of freedom using pneumatic actuators, and the models of actuator and 2-link arm is constructed. A control PID control system is constructed, and the gains of the PID control system are determined by the simulation that uses the model of 2-link arm. The step response of the joint angle is examined. Control performance of the PID control system is verified.

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In this research, we have developed the pneumatic robot arm driven by pneumatic actuators as the versatile end effector of a material handling system. The arm consists of the hand and wrist parts. The hand can grasp various objects without force sensors and feedback control. Therefore, we aim to control the wrist motions to expand the hand motion space. We construct the experimental models of the drive system of the pneumatic robot wrist. We design the control systems using simulations with the constructed models. After that, we try to control the wrist motions with constructed controllers. As a result, we can control the wrist motions with constructed PI controllers. The wrist models are coincident with the motions of the wrist accurately. Therefore, we can get the experimental results that meet the simulation conditions.

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In recent years, Japanese society has been aging, engendering a labor shortage of young workers. Robots are therefore expected to be useful to perform tasks such as day-to-day work support for elderly people. Then, tendon-driven balloon actuator has been developed for the robot hand in such environments. In this study, we have evaluated characteristics of force control of balloon actuator using predictive functional control (PFC) system. The predictive functional control is one of the model based predictive control (MPC) schemes, which predict the future outputs of actual plant over prediction horizon and compute the control effort over control horizon at every sampling instance. In this paper, PFC control performances of 1-link finger using pneumatic balloon actuator are reported.

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This paper proposes an active hose to explore the narrow and complex space. This hose has the following two characteristics. One is that top of the hose grows by air pressure from within, and the grown part of the hose becomes hard and guide hose. The other is that the diameter of the hose can be changed according to the number of tube units. This mechanism is confirmed by experiments.

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This paper evaluates a inchworm drive and a ciliary vibration drive for Active Scope Camera which is a snakelike rescue robot used in disaster environments. The conventional Active Scope Camera already mounts the ciliary vibration drive. In this paper, the authors propose the mounting not only the vibration drive but also the inchworm drive. The inchworm drive developed in this paper is effective on soft roads, uneven roads and inclined roads. The authors especially focus on the running experiments on the road-surfaces which exist in disaster environments.

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We developed the Active Scope Camera by the Ciliary Vibration Drive as a snake type Rescue Robot. Moreover, to make it possible for Active Scope Camera to run on the soft road and intense ruggedness road where the it cannot run by the Ciliary Vibration Drive, we also developed the Inch-worm Drive used frictional anisotropy. However, the flexibility of the Active Scope Camera decreases because it uses the hard Pneumatic Cylinder as a Linear Actuator. In this paper, we propose a Flexible Cylinder to solve this problem. In addition, we made the prototype of Flexible Inch-warm Drive used the Flexible Cylinder and valuate driving performance of it by comparing with the past, Active Scope Camera.

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The purpose of this study is the development of the valve that can precisely control pneumatic cylinders. The valve that has a lightweight and simple structure and uses piezoelectric oscillator which is driven at resonance mode and it can control flow rate by controlling the amplitude of the particles excitation. We reported this flow control valve principle in the previous paper and concluded the diameter of orifice is an important parameter for flow rate change. In this report, we have designed a new prototype for the purpose of high controllability. We have measured flow rate characteristics and observed particle motion. From these result, we confirmed the conditions necessary for continuous adjustment of flow quantity by experiment.

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The purpose of this study is to develop a portable energy-saving type air supply system. A variable volume tank is developed in order to drive a pneumatic actuator with a low discharge pressure in a tank. The developed tank composed of flexible materials can store a pneumatic energy by converting it to an elastic energy. In this paper, the composition of the system, the structure and characteristic of a variable volume tank and experiment of drive actuator using constant and variable volume tanks are shown. As a result, a variable volume tank can drive the actuator at low pressure compared with the constant volume tank.

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Differential rotary to linear conversion mechanism with three precision ball screws and three spur gears were designed in order to evaluate the positioning accuracy and the input-output characteristics under the applied output load. In the positioning accuracy test, the positioning accuracy of this mechanism was almost equivalent to the accuracy of the precision ball screw employed in the test model. In the input torque-output load conversion test, the output load per unit input torque of this mechanism was larger than that of the feed screw mechanism. These results revealed that the differential rotary to linear conversion mechanism with three precision ball screws and three spur gears has the characteristics of both high positioning accuracy and excellent input-output conversion efficiency.

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When a robot system is developed by normal motors that rotate around one axis, the necessary number of motors is the same as that of joints resulting in a large and complicated system. On the other hand, spherical motors will realize a small and simple mechanism because they can rotate in various direction. A group of spherical motors that can rotate in 360 degrees is proposed by applying the working principle of planer stepping motor to spherical motors. There are various types in arranging permanent magnets on the rotor and electro-magnets on the stator. This study utilizes the arrangement in which a permanent magnet is placed on the apex of a truncated octahedron for the rotor and on electro-magnet is placed on either the apex of a regular dodecahedron or the middle point of two apexes for the stator. This study develops a spherical motor that can rotate around six axes and demonstrates the rotation around their axes.

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Pseudo-mechanism is a drive/control system with a worm gear and force assist control. It can change the mechanical feature by switching the force assist control or without control. The motion of this system seems to be sometimes a one-way clutch, a torque limiter, spring and so on. The vibration may occur caused by force sensor feedback. Some improvements of vibration compensation control have been tested successfully. If this system is applied in a vibration environment, it can move a heavy object by using the external force. The feasibility of this concept has been clarified experimentally.

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The purpose of this work is to develop a flat electromagnetic wobble motor which is 30mm in diameter and 5mm in thickness can be applied to portable electric equipments. In this paper, first, the basic structure, driving principle and control method are presented. Next, the motor drive experiments using three types of gear pairs are shown. As a result, the motor works successfully.

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Because Rescue robot is used in various types of environment and running conditions, the robustness is essential for actuators used in the drive systems of robots. The new type actuator, we named Super-Robust HFD Electrical Actuator, has been developed. This actuator consists of the electric motor and the friction transmission type flat belt that protects the drive train from the impact overload. The fundamentals and mechanism of this actuator system is reported in this paper.

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We are developing a low backlash reducer using precessing crown gears. We call it crown reducer. The features of this reducer are low backlash, high reduction ratio, back-drivability, and advantage in miniaturizing. These features greatly contribute to design various small mechanisms such as a finger joint of a robot hand. In this paper, we describe some modifications of mechanical design about the output shaft for improving transmission torque capability of the crown reducer. Calculation results of the newly designed crown reducer by using FEM are shown in this paper.

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Cell manufacturing system is suitable for wide-variety product manufacturing. However able workers are needed in order to realize the cell manufacturing system. To solve this problem, robot cell manufacturing is researched recently. For the robot cell manufacturing, not only advanced intelligence but also excellent hardware such as actuators is necessary. In this report, an actuator suitable for cell manufacturing robot hand is proposed. Experimental device of the proposed actuator is designed and assembled. The motion of the actuator is observed and it is confirmed that the actuator can control the position and the speed of the output. This experimental result shows the effectiveness of the proposed actuator.

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This paper presents a totally-enclosed valve using a load-sensitive continuously variable transmission. This valve is driven by vibration motor. It consists of a screw and ball, and is remarkably simple and compact. We have developed the valve of 2.8 [g] and a vibration exciter of 20.1 [g]. We have experimentally verified that the developed valve works at an air pressure of 0.2 [MPa].

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This paper describes the development of an actuator which head grows just like a plant's root. This actuator is composed of a tube which shape is similar to a pipe. The advancing motion is promoted by drawing out the folded tube after flattened by vacuum suction inside it. In the preliminary experiment, it advanced without generating sliding friction between its surface and debris under the pressure of 0.1 MPa. Steering motion is achieved by changing the restraining condition of surroundings of the tube. Using this actuator enables to develop the robot which is able to advance inside the pipe line which curves three dimensionally without generating sliding friction.

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This paper proposes a new open-loop control method for the velocity control of a DC motor without any external sensors. This circuit system for motor control consists of a DMOS full bridge motor-driver (L6203) and a current controller (L6506) which is usually used for stepping motors. This system allows of PWM signals that is input to the corresponding terminal of the L6506, which work as a velocity command. This paper demonstrates that the motor velocity increases linearly according to the change of duty ratio of the signals without using feedback schemes by the sensors. In addition, it is clearly shown that the motor velocity gradually decreases as the frequency of the signals increases, resulting in approximately 25% fall between 200Hz and 1700Hz.

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Electro-active polymers have received great attentions as a new class of soft actuators. Ionic polymer-metal composite (IPMC) is one of the electro-active polymers, and can be operated in wet conditions and exhibits large deformations under low input voltage. This paper presents a method to improve the IPMC relaxation phenomenon. The relaxation phenomenon reduces generated force magnitude and displacements of IPMC as time passes. To reduce the relaxation phenomenon, we propose a new structure in which two IPMC sheets work cooperatively and a control system that applies reverse phase high-frequency signals to control inputs for each IPMC motion. Simulations and experiments confirm the effectiveness of the proposed method.

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This paper proposes a new energy saving method bf mechanical systems with elastic elements. In the proposed method, elastic elements are used to store dissipated energy as potential energy for periodic motions based on resonance. We propose an inertia adaptive control method in which a mass is moved in order to change the moment of inertia and change the desired motion cycle. Performance bf the proposed method has been demonstrated through several simulation results.

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This paper describes a sensing method for motion of a spherical surface. The method uses two or more optical mouse sensors, detects circumferential speeds of the surface, and transforms those speeds into angular velocity of the sphere. It can be also applied to a flat surface sensing by assuming that the radius is infinity. With weighted average of multiple combinations of sensor outputs, the experimental result showed only 1% error in sensing. A particle filter based absolute estimation method was also introduced. It compensates the position error by using pattern-filled surface and reflection sensing of mouse sensors. The method was examined through simulation on a flat surface, which showed effectiveness of the improved method.

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This article proposes two friction compensation methods based on the LuGre model. One is based on a time varying disturbance observer that uses locally-linearized LuGre models. The other uses a feedforward-driven LuGre model with a type-1 disturbance observer (Dual DOB). To show the validity of the proposed method, experiment for a positioning control system affected by friction was conducted. From the experimental results, it was confirmed that the proposed friction observer can eliminate influence of friction and that it is effective for improving positioning accuracy. Future work would be to analyze stability of the time-varying disturbance observer based LuGre model and to modify the disturbance observers taking into consideration calculation time delay.

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This paper shows a double admittance control of the finger-arm robot. The double admittance control realize natural soft move by virtual dynamics in each finger and arm robot. The stiffness test of the finger-arm robot show that the double admittance control realize soft movement. And the double admittance control kept good manipulability of finger, although the control hadn't complex algorithm like previous control systems. Therefore the double admittance control showed soft move due to simple physical performance. Then in comparison between finger and arm movement, an arm had a little delay in the movement. This movement is like movement of human upper limbs, so the double admittance control may be the close to human model.

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We have proposed a mechanism that enables an output axis change and the selected output axis drive using only one motor. In this paper, the mechanism is applied for mobile robot, which enables the robot move on two-dimensional field. First, the way how the axes are connected with is considered. Next, the robot with proposed mechanism is made by pulley and rubber belt, and examined by experiments. As a result, some problems appear. Finally, the solution approach is introduced.

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In this study, a flat microscope stage has been developed for the micromanipulation operated for the microscope. This stage has been developed for installing in the biological microscope that uses 40 times object lens. Design specifications of the stage are as follows. (1) The operational range of stage should be 100μm×100μm×10μm or more. (2) The responsibility of the stage should be 1Hz or more. (3) The positioning performance of the stage should be 1 urn or less. (4) Practicably, the stage should have a compact size to secure operator's work space. To satisfy these specifications, we introduced the principle of operation of the electromagnetic actuator using rubber to the drive system of the stage. The sample stage supported by flexible rubber is driven by electromagnetic force with high-precision. Effectiveness of this stage to the micro manipulation system operated for the microscope has been confirmed.

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The purpose of my work is to develop an actuator using a coiled shape memory alloy (SMA) for an artificial arm. We manufactured the SMA actuator for drive of the finger. The SMA actuator consist of a coiled SMA wire which is a diameter of 0.7 mm and an aluminum case which is a height of 10mm, a width of 9mm and a length of 153mm. Two SMA actuators are used to move one finger. The SMA actuator for bend motion is connected to the upper surface of the fingertip, and the SMA actuator for extension motion is connected to the undersurface of the fingertip. The prototype model has the maximum force of 6.6N. This paper describes the design and experimental results of the developed actuator.

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The cyclo gear reducer has a deceleration ratio of engagement that is two and three times higher than the usual spur wheel or involute gears. Since the curved shape of the teeth used in an epitrochoid gear are not sharp, the gear can be made using a 3D processing. Our purpose is to develop the cyclo gear reducer that can semi-continuously change the deceleration ratio by installing the mechanism where the slide moves along the direction of the rotation axis in the epitrochoid gear, as one of the applications of the cyclo gear reducer.

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This paper reports on the development of a new hydraulic bilateral servo actuator which consists of a master internal gear pump and slave double motion cylinder. From the demands on portable and compact structured controllable actuator for robotic system, hydraulic bilateral servo actuator was developed. To improve the portability the system needed modification of the master unit. A prototype internal gear pump master unit was developed and tested of its dynamic characteristic of driving the slave cylinder piston. The piston rod was loaded with maximum 3kgf and the open loop control characteristic was measured for lump response. The system responded stably for loads less then 0.7kgf. However a feedback controller is required for better performance to apply the system for target robotic limb control.

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Electro-Conjugate Fluid (ECF) is a kind of functional and dielectric fluid. When a high DC voltage is applied to a pair of electrodes immersed in the ECF, a strong and active jet flow of ECF (ECF-jet) is generated between these two electrodes. A high power tube-type ECF micropump that consists of triangular prism and slit electrode pairs was proposed and fabricated by MEMS technology including photolithography with thick photoresist and nickel electroplating in the previous report. In this paper, we present advanced ECF micropumps in which the electrode pairs were serialized and parallelized for high performance in demand. The experiment results of the ECF micropumps show that parallelizing the electrode pairs does not affect output pressure significantly and also prove that the flow rate is proportionally dependent on the number of parallelized electrodes.

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In this paper, the design for the amphibious multilegged robot is proposed and the performance by the prototype model is described. Enhanced mobile performance of walking robot is required on the field of environmental adaptation. Amphibious robot is expected to shorten travel time.

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Snake-like robot is a hyper-redundant mobile robot with an articulated body composed of serially-connected modules driven by actuators. Recently several hyper-redundant mobile robots have been developed in hope of the versatility brought from its simple form. Snake-like robots have been developed aiming at its applications to operations dangerous to man: the in-pipe inspection at chemical or nuclear energy plants and the rescue of victims under collapsed buildings by making use of its flexible and slender shape, and the mine detection by distributing its own weight on the ground and so on. In this paper, the novel mechanical design is proposed to enhance the mobility for various environments, and a prototype model is composed of serially-connected modules with suctions. The performance of the prototype model is described.

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This paper shows a new mechanism that is designed for a stair climbing robot. This mechanism is proposed for a rescue robot that moves to search for victims in crashed buildings. To realize a simple construction of rescue robots, the mechanism is driven by only one motor to climb a stair. Results of experiments with a half-sized real robot and simulation with a virtual robot are compared in a view point of motion analysis and show the effectiveness of the mechanism.

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There are many various movements in the natural world. Peristalsis motion like an earthworm is useful to progress in any confined spaces. In this study, our purpose is development of earthworm robot which is useful to progress in the narrow pipe. An actuator of the earthworm robot was BioMetal Fiber (BMF series) which is one of the shape memory alloys. BMF, elongated at room temperature, becomes stiff and sharply contract when a current is fed through it. The mechanism of using BMF is lighter and smaller than any other mechanisms, such as DC motor, servo motor and air pressure.

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The double-spiral-propulsion robot has been proposed to support field survey activities in wetlands. The robot consists of two pairs of spiral pipes and eight 4-DOF manipulators whose grippers handle the spiral pipes. The kinematic relations among manipulator's components were established through D-H method. The three-dimensional model of the manipulator is established in a dynamic simulation software. The process of the manipulator gripping spiral is simulated. The joint position and joint internal position error curves are obtained. Those results show that the proposed manipulator possesses high controllability. The torque on x, y, z-axis of revolute joint2 and joint4 are also measured by torque sensors for detailed design in future work.

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"RT-Mover" can move on countinuous rough terrain by using the basic moving control technique. And it can move on discountinuous step by using the step-up-gait. There is, however, stability margin of RT-Mover declines when using by the step-up-gait. In this papar, we improve stability margin by using a seat slide control.

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To realize the piping inspection from the inside, mobile robots which can travel long distance in the pipeline are necessary. So, we propose new mechanism for in-pipe robot in this paper. This mechanism "ThesV" has multiple spherical wheels and controls the posture by pulling two wires going through the body. By applying connected differential mechanism, ThesV can adapt the posture to the pipe shape and support its body against the internal wall of the pipe without complex control. And it can rotate on pipe axis and select course in T-branch with simple mechanism. Finally, through the motion experiments: experiment of velocity measurement, rotational motion, moving in vertical pipe, passing elbow and course selection, we showed usefulness of the concept.

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Variably Configured Segmented Wheels (VCSW) for driving on snow can be available for snow rescue robot. However, because of many irregularities on the snow road, it is necessary to improve the performance of ground contact. Free joint mechanism is equipped with four-wheel vehicles as the suspension. In addition, another free joint is also applied to improve steering performance. All four wheels of the vehicle are controlled by speed servo systems. Effectiveness of the speed servos are tested successfully. Step climbing experiment, the vehicle surmounted high step which is 93% of wheel radius. Turning experiments to improve the steering performance show the necessity of yaw control.

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Before now, there are tires, crawlers, legs as locomotion strategies, and they have been considerable research on locomotion strategies. One of those locomotion strategies had been research on a vibration, but they are almost using cilia. In addition, there is vibration carrier machine without cilia. The degree of freedom of the design spreads if cilia are not necessary and only arrange vibration motors. Therefore, we have been studying on a hemisphere movable body with vibration motors. Until now, we have confirmation of behavior at two vibration motors. In this paper, we report about behavior to hemisphere movable body with three vibration motor.

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In recent decades, the devastating earthquakes, which can damage a lot of houses and buildings, have fre- quently happened. To slow down or prevent the disastrous damages of the earthquake, the various technologies have been required. Of these technologies, the ground motion simulator of the earthquake is used to alert people to the dangers of the earthquake. The authors have developed a potable earthquake simulator, called a Zishin-The-Vuton, which has the function to make holonomic omni-directional motions of the earthquake on a plane. In this paper, the more advanced simulator Zishin-The-Vuton 3D is presented. It realizes the up-and-down motion with the holonomic omni-directional motions in order to simulate three-dimensional ground motion of the earthquake. Focusing on the design concept, structure, and feature of this new simulator, we discuss its implementation and validity.

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In this paper, we propose a new design of a mobile spherical robot, which is composed of a sphere-shaped outer shell and a 2-d.o.f. eccentric rotors inside it. On the assumption that there exists rolling contact constraint between the spherical surface of the robot and the floor, we construct a dynamic model of the robot and search the dynamic equlibrium. We finally achieve locomotion control by utilizing the principle of holonomy with appropriately oscillated rotors.

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Wheels and crawlers are commonly used in existing mobile robots. However, a robot with wheels or crawlers cannot be easily sealed against water and dust. In this paper, a new propulsion mechanism named "Surface Wave Mechanism" is proposed. It can generate propulsive motion by small scale rotating motion on the propelling surface. The main feature of this mechanism is the simple structure and it can be entirely covered by rubber sheet and becomes water-proof. Surface Wave Mechanism would have a wide range of application in the future such as inspection robots or rescue robots. Both planer and circular prototypes of this mechanism were designed and the performance was evaluated by experiments.

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In extreme environments, such as lunar surface or volcanic area in the earth, exploration by mobile robots instead of human is considered of value from the point of view of safety. However, such a natural environment is uneven, and usually, it is covered with rocks and/or loose soil. Thus, the mobile robot is required to obtain a high traversability. So, we have been developing a mobile robot that equips both a simple leg motion and tracked locomotion to traverse weak and rocky surfaces. To evaluate its performance, in this research, we conduct a stability analysis of the mechanism. In this paper, we introduce the mechanism of our developing mobile robot, explain a robot, and discuss the stability analysis.

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