Recently, teleoperated robots are expected to do search and rescue activities in a disaster area. The usual teleoperation system of robot relies on camera images. However, it is difficult to get an effective camera image in a confined space and it forces a large burden on the operator. In this study, a teleoperation system to get an effective camera image automatically is proposed in order to reduce the operator's burden. Our system shifts camera's position automatically on the basis of information about obstacles surrounding a robot. At first, in order to understand which kind of camera images are effective in a confined space, we carry out the experiment with a simulator. Secondly, we carry out the experiment to verify the effectiveness of our proposed system based on the results of the first experiment.

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Recently, rescue robots are expected to perform the work on behalf of people in hazardous locations where people cannot enter easily. For rescue robots running at the rough terrain, rollover fall is fatal. Accordingly, various studies to reduce the burden of falling avoidance operation is proposed. However, in these studies, implementation is hard and estimation accuracy is reduced in the complex terrain. In this study, we propose an easily implementable and highly accurate system to assess fall risk using a 3D depth sensor. In the proposed system, we mount the depth sensor on the robot to reconstruct CG models of the environment and the robot in a virtual space. Normalized energy stability margin are calculated from the estimated points. We verify accuracy of the time of fall down calculated by the proposed system comparing to the existing study, by using a dynamic simulator for mobile robots.

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To introduce a robot into human-dominated environment, its actuators should be both force sensitivite and powerful. To realize force sensitivity, we have been proposing intrinsically backdrivable electro-hydrostatic actuators(EHA) and their effectiveness in force sensing. However, in order to enhance the backdrivability, we sacrifice power efficien y of the actuator. To cope with both backdrivability and high power efficieny, hydraulic cylinder was introduced in an EHA as an output. In this paper, the property, including backdrivability and dynamic characteristics, was evaluated on the developed EHA with hydraulic cylinder. To evaluate dynamic characteristics of the EHA, we used inertial load. We developed an experimental device for dynamic characteristics evaluation.

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Force sensitivity is indispensable feature for a robot actuator. To enhance force sensitivity, backdrivability of an actuator is vital. We have been proposing intrinsically backdrivable electro-hydrostatic actuators(EHA) and their effectiveness in force sensing. However, in order to enhance the backdrivability, we sacrificed power efficiency of the actuator. To restrain power loss, we introduced a hydraulic cylinder in an EHA as an output. In this paper, we present design detail of linear EHA that is going to be used for the force sensitive ankle joint mechanism. Furthermore, we evaluated static characteristics of developed linear EHA.

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The actuator for robot hand need to be powerful enough to hold its whole weight and flexible enough to avoid damage by the collision with the environment. We developed a back drivable 14 degrees of freedom electro hydrostatic cluster actuator for tendon driven robot hand combining direct casted cylinder manifold and trochoid gear pump with crescent separator. Its basic design and prototype was showed previously. In this paper, we finished it as a cluster actuator and evaluated its static property such as maximum output force, moving speed and their dispersion. Its ability of force measurement is also evaluated.

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This paper discusses a food texture evaluating system for gel foods. Considering the relationship between oral temperature and melting temperature, we propose a method to estimate value of sensory evaluation by using the experimental system with heating function. Experimental results show that the values of sensory evaluation in four kinds of food texture are accurately estimated, and the temperature dependency is different between four kinds of food texture.

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When thermal stimulation is applied to one place and tactile stimulation is presented to the other place on the skin, we also perceive thermal sensation on the latter place. This illusion, known as Thermal Referral (TR), was well studied in fingers and forearm. However its characteristics in other parts of the body was seldom reported. We conducted an experiment to verify the difference in TR occurrence rate in four places along from the chest region to the right hand. The result indicated that TR occurrence rates when the stilumi were over the wrist or the median line were very low.

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Vocabulary learning is considered one of the most time-consuming parts of language learning. Considering the fact that we generally memorize words by associating them with other cues, and one such cue is tactile sensation, we propose to use tactile vibration cues for vocabulary learning. In this paper, we developed a device that can replay vibration resulting from keyboard typing, and presented studies on efficacy of a device.

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Vibrotactile texture stimuli have been commonly used for roughness presentation. The extension of such stimulation to other textural modalities benefits their applications. We found that laterally asymmetric vibrotactile stimuli cause the sense of friction rather than vibration. When the vibrotactile contactor moves one way, it sticks to the finger pad and induces lateral skin stretch. In contrast, when the contactor moves the other way, it slips due to its quick motion and involves little skin stretch. As a result, humans experience frictional sensations in scanning the contactor. We examined subjective responses and measured interactive forces between the finger pad and contactor. Both perceptual and physical experiments corroborated the principle of friction display. The laterally asymmetric vibrotactile stimuli increased the finger pad skin stretches and sense of friction. Such frictional display widens the capability of traditional vibrotactile displays and fosters its commercial values.

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Recently, the touch panel has been widespread as computer interface. Using the touch panel is easy because of intuitive operation, but it is difficult for a visually impaired person who cannot get the visual information. In order to improve this problem, tactile display using sheet-like ultrasonic transducer has been developed in previous research. By this device, when a touch panel is operated, user can get tactile feedback, and it is possible to recognize an icon and a window. However, at the present stage, it cannot be mounted on a large-sized touch panel. So, we aim at development of tactile display using sheet-like transducer which can be mounted on a large-sized touch panel. In this paper, evaluation of the couplant used for the sheet-like ultrasonic transducer is reported.

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We often clean others' ears for the purpose of hygiene and communication. However, it has a risk of injuring the ears by applying too much force because it is difficult to grasp movement and position of an earpick. To solve this problem, we present novel techniques to provide cues for grasping behavior of the earpick using auditory feedback. We implemented two techniques: 1) ear-picking sound feedback and 2) audification of the force applied to the ear canal. We conducted two experiments to study whether these two techniques can help users control the force. Contrary to our expectation, the results of the first experiment showed that the ear-picking sound feedback had no effect for helping the force control. The results of the second experiment, on the other hand, showed a marginally significant effect that the audifcation of the force reduced the force applied to the ear canal. It indicates that the audification of the force helps users control the force.

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In this paper, for sorting work of valuables and waste, which is done manually, such as building demolition, construction waste by the industrial robot and robot vision for the purpose of efficiency, improve safety and increase waste recycling rate I describe the practical application of the construction waste sorting system.

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A method to autonomously control multiple environmental cameras for providing more adaptive visual information suited to the work situation for advanced unmanned construction is proposed. Situations in which the yaw, pitch, and zoom of cameras should be controlled were analyzed and imaging objects and imaging modes were defined. To control each camera simply and effectively, four practical camera roles combined with the imaging objects and modes were defined. A role assignment system was then developed to assign the four camera roles to four out of six cameras suitable for the work situation, on the basis of the assignment priority rules. Debris removal tasks were performed by using a VR simulator to compare fixed, manual control, and autonomous systems. Results showed that the autonomous system was the best of the three at decreasing the number of grasping misses and increasing the subjective usability while improving the time efficiency.

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The concrete-wall-climbing hammering tester, "Rising Cross II" has been improved. This Rising Cross II is a robot which climbs and tests concrete structure. The height which the Rising Cross II could test was limited to five meters because the bundle of the power cables was heavy. Each of the power units had a power cable which was connected to a controller on the ground. Then, the mount of cables has been reduced by installing a switching unit on Rising Cross II. Furthermore, pressure sensors have been installed on the suction cups to improve the reliability of the adhesion. The new type of the climbing hammering tester, Rising Cross III can climb and test concrete walls over ten meters.

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Aiming at laborsaving of the conveyance work of interior materials, the authors developed the automated conveying system which can respond to change of a situation peculiar to a construction site flexibly at low cost. The IC tag signboard which specified the conveyance place is only put on material used on the spot, a diving typed AGV (Automated Guided Vehicle) can load material automatically, and this system can convey it in the purpose position. Moreover, since it can set up simply only by using magnetic tape for a conveyance course and sticking on a floor, the course change by re-covering is easy. Thereby, compared with the conventional carrier system, conveyance work could be economized to about 1/2〜1/3, and it checked that workers could be collected to skill work.

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When asbestos existence is investigated and asbestos is before demolition of a building, it is obliged to remove appropriately, and to carry and dispose. Writers are developing the system which screens wide angle asbestos containing construction materials quickly with a near-infrared camera. The screening technology of chrysotile with most amount of the construction materials used was developed, and it experimented on site, and compared with the analysis result of the regulating method. In this paper, a principle and an outline are introduced and the result of an accuracy verification experiment is reported.

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Authors have developed an autonomous control system for loading rocks on a dump truck which can make arbitrary shapes of a rock pile on the loading platform. In order to realize such a system, it is necessary to analyze the behaviors of rocks fallen from the bucket of the wheel loader. However, the calculated shapes based on the behavior the bucket are not enough. Therefore the rock behaviors are carefully observed by a new developed image processing system and the mechanism of slope failure of rocks in the bucket in this paper.

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This paper describes on the estimation method of compressed strength for the concrete construction such as highway roads, large bridges and institution, and the autonomous mobile robot with that the small sized perforation drill. In the control using the torque motor, the feed rate of drill is expected to be a constant as the torque depending on load. However, the forwarding speed was found to change for concrete strength and to be the approximately constant to concrete strength when the load with more than of setting torque acted on a drill. As a result, the comparison of the concrete strength and drill feed rate was able to express by logarithm approximation curve. Installing this inspection system on a mobile robot, we got the possibility that automatic estimation of concrete strength was carried out easily at construction site.

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Block caving is one of the popular methods for underground hard rock mining. In this method, two processes are mainly required, excavation at drawpoint and transportation of ore from drawpoints to ore passes. We propose an approach that excavation and transportation functions are allocated to different machines to increase productivity. The excavation machine consists of a manipulator for raking ore and a feeder for loading ore into a transporter. A one-tenth scale model is developed for a feasibility study. This scale model comprises excavator and a draw point environment. Using the model, a performance evaluation experiment has been conducted. The results reveal that the contact point of raking rotor and motion of the manipulator have large impacts on the productivity. In addition, detections of arching and large blocks are key technology to keep the high productivity of the proposed excavator.

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Unmanned robot operation is highly expected in a hazardous environment such as a nuclear accident cite. We propose an automated construction system of robot locomotion and operation platform in a seriously disturbed environment where utilizable sensors and actuators is restricted. Its purpose is to make specialized working robots reach at any points. Each structure for locomotion and operation is modularized, and constructed by cooperation of a transfer robot and a constructor robot. This paper describes development of prototypes and experiments to verify the feasibility of module-transferring and connection motions in typical three positions. The feature of the developed robots is that they use guide structures to reduce the effects of mechanical error and misalignment between robots.

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Existing tele-operated construction machineries are by far less efficient than directly operated ones. In fact, principal factor of inefficiency of the systems have not yet clearly determined. The authors developed a prototype tele-operation platform to examine tele-operation factors such as image presentation method, sound, vibration and time lag. In this paper, preliminary operability evaluation experiments using the platform are performed from image presentation aspect. However, the results were affected by fusion of three factors (image presentation, responsiveness of the operation subject, and skill of the operator) and difficult to separate into individual operability factor. In order to solve this problems, the responsiveness of the operation subject was improved. In addition, an operating method to exclude operator's skill was devised. The improved platform is tested by comparing 3D and 2D image presentation methods. The results demonstrated characteristics of 3D image properly.

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In recent years, tele-operation of construction machineries has been intensely investigated in order to improve the working environment for their operators in the construction field. Vision is an important factor for the understanding of the environment in the remote control. However, the relationship between the operability and the resolution of presented image has not revealed. In this study, we evaluated the influence of the resolution of presented images for sense of presence and perspective among three resolution levels (SD, HD, 4K). The experimental results suggest the trend that both sense of presence and perspective improve as the resolution of presented images becomes higher.

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In this paper, we focus on the instability dynamics of excavator, which lead to unexpected displacement. In order to analyze the turnover phenomena, we develop simple excavator model named Dempsi, by applying the principle of a tripedal walking robot 'Martian ll'. By exciting the heading and the boom angular velocity to the robot simultaneously, we examine the motion analogy between the different scale models, from the viewpoint of the oscillation and displacement.

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Execution in hazardous area needs teleoperation system, and unmanned construction system are adopted into many scenes. This system use many unredeemable cameras and a lot of onboard camera for understanding robots environment. Operators have to learn depth form a multitude of the screen shows robots or the surroundings. The operator needs good skill and experiences. To solve this problem, we must show environment to know something intuitively. In dealing with such situation, we will report about the system of make three dimensional map sequentially, using a remote control robot load with stereo camera, and also it shown by polygon mesh.

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We propose a robot hand mechanism for sorting construction byproducts on a belt conveyor. The byproduct that cannot be grasped is manipulated for pushing by the tilt bumper. In order to avoid getting over the thin byproducts, it has a passive slider. In order to avoid lateral missing of the byproducts during the pushing action, it also has two ribs on bumper side. The bumper also has a tilt function as a safety device to avoid the overload. Graspable objects are grasped between two claws and the bumper. If there are other byproducts in the path, it can be avoided by grasping it and lifting it into the air.

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It is necessary a person moves a construction machine by remote operation from the safe place, and to work to perform the restoration activity by mud flood disasters quickly safely. Therefore I could easily attach it to a commercial general-purpose oil pressure shovel and developed the remote operation robot which I could operate from remoteness and applied it. I report the measures with having become the problem in the use.

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Prevention of collision accident between heavy equipment and light vehicles is one of the most critical issues in mining industry of all over the world. Operators of heavy equipment usually check the surroundings by their direct eyesight and through the mirrors mounted on the machinery, nevertheless they have felt some difficulty in getting the picture of proximity. We developed a system for supporting safety check of operators, named as "SkyAngle", which can provide all-around picture as a bird's-eye view. This system consists of multiple cameras, image synthesis controller, and LCD monitor. This report introduces the requirements, functionalities, and characteristics of the system.

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Remote control of construction machines has been considered to ensure safety of operators in hazardous works such as indoor dismantling. However, work efficiency of the remote operation is lower than that by the on-board operation and the number of skilled operators of construction machines, especially who are accustomed to the remote operation, is decreasing. Therefore, intuitive and efficient remote control interfaces for construction machines are required. In this paper, we design and evaluate several control interfaces for remote control of a small-size backhoe, aiming at high work efficiency nearly equal to that by the on-board operation. We investigate two control methods, joint control and end-point (tool) control. As for the control interface design, we propose some new controllers including a master-slave-type controller and evaluate their performance from various viewpoints, comparing with the conventional controller. The results of the evaluation test show that the proposed controllers are better than the existing controller in working efficiency, low fatigue, and intuitiveness.

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Redundant manipulators are expected to be effective for the tasks in cluttered environment with many obstacles such as disaster sites and atomic energy facilities. However, it is difficult for the operator to maneuver such redundant manipulators intuitively because there are many possibilities to select self-motion patterns when the manipulator is highly redundant. In this paper, a 9-dof redundant manipulator is chosen as a target of study and an intuitive self-motion pattern is proposed so that the operator can easily maneuver the manipulator to avoid obstacles and some undesirable postures. Comparison experiment, obstacle avoidance task in a simulator, is conducted to confirm the advantage of the proposed method over some naive methods for determining self-motion patterns. The experimental results shows that the proposed method improves the task efficiency and enables the operator to maneuver the manipulator flexibly in various obstacle conditions.

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The Roller-Walker is one of wheel-legged hybrid mobile robots. It has passive wheels on the tip of each leg and locomotes by the similar principle of the roller skating. The motion of the Roller-Walker is able to be discussed as a system with nonholonomic constraints by assuming each wheel does not slip sideways. In this paper, a two legged Roller-Walker is considered, and we derive the condition for generating a straight motion and a pivot turn motion based on the nonholonomic velocity constraint of wheels. Moreover, we developed a two legged Roller-Walker, and a straight motion, a pivot turn motion and a right or left turn motion are achieved by experiments.

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In this paper, we consider a nonholonomic aerial mobile robot in tetrahedral shape with six fins mounted on its edges. From a viewpoint of nonlinear control theory, this robot is in the class of first-order driftless system with six inputs, where its controllability Lie algebra is generated nonholonomic aerial mobile robot considering its symmetry with respect to spatial rotations, and investigate its locomotion principle (e.g. translation and rotation) as well as fundamental control algorithm.

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This paper is concerned with feedback control of the trident snake robot, which is an example of wheeled mobile robot described as a nonholonomic kinematic equation with three control inputs and six state variables. Based on the authors' previous work on controlling nonholonomic system by using neural oscillators with strong entrainment property, we propose to apply artificial disturbance (stimulation) to the neural oscillators to generate translational locomotion in the prespecified desired direction. We also design a feedback control scheme by assigning the disturbance as a function of current direction error to the desired one.

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A cube indicates some interesting properties such as changing its top faces when it rolls around on the ground without slip. This property originates in cube's shape and rolling constraints. In this study, we have tried to develop the cubic mobile robot which utilizes its rolling constraints or ordered shape originating in its cubic shape. This paper presents the development of the cubic mobile robot whose locomotion depends on the rolling constraints and the inner mass manipulation. The inner mass manipulation is generated by two motors attached the masses on their arms. As the first step of the development, the fundamental rolling experiments were carried out.

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To improve the adaptability of the snake-like robot in complex environments, we developed a snake-like robot with a prismatic joint. This robot can not only perform the serpentine gait, but also the peristaltic gait like an earthworm. In this research we restrict our attention on the peristaltic locomotion to access a narrow space. The one-way clutch mechanism is used to substitute for the passive wheels to obtain enough friction force in peristaltic locomotion and a basic peristaltic sequence is proposed to realize the peristaltic gait. Experiments are carried out to verify our mechanism design.

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This paper presents plug-in automatic charge of omnidirectional mobile robot with active casters. In this system, a camera on the robot detects an outlet on wall and a plug on the robot is inserted in the outlet by only movement of robot. Because this system needs no stations for automatic charge of robot, this system provides space saving and improvement of efficiency for robot task. Outlet is detected by feature values of contours. Distance and angle of outlet are measured by geometric relation of object and picture. Furthermore, it is confirmed that camera enables robot to approach outlet by experiment. Hereafter, robot will be installed plug and experiment of plug-in automatic charge will be tried.

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The circular cross-section crawler has been done in the previous research. The unit is featured by generating two orthogonal oriented driving forces by contacting of the external environment. In this research, the crawler unit is composed of two curved crawler belts to realize whole surface omnidirectional driving. The prototype model is designed and developed. The basic motion of the prototype is confirmed experimentally.

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In this paper the analysis of the disturbances that enter the system of a wheeled inverted pendulum type assistant robot is presented. Using null space techniques the equilibrium conditions under the presence of disturbances and the subsequent effects on the system is determined. A new controller based on the Extended State Observer is implemented to counteract these effects. Results of experiments comparing the new and previous control for both load carrying and ramp climbing are discussed and presented.

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In this paper, we propose a palm-top jumping robot based on snap-through buckling of closed elastica for stair-climbing. The proposed robot is a modified version of an existing robot using spatially deformable arch-type closed elastica, but has much higher jumping capability due to the following two effects of the fi-shaped frame. One is appropriate elasticity for supporting the elastica, which drastically enhances the ability to generate impulsive forces for jumping. The other one is easy adjustment of the mass balance of the robot so that the tip of the leg attached to the closed elastica, with which the robot applies the impulse force to the ground, pushes near the ground point below its center of gravity. Experimental results using a palm-top prototype with 36 [g] weight show that the compact and light-weight robot can jump over about 20[cm] corresponding to the height of a step of a normal stair in spite of having 14[g] payload. The robot has potential to achieve quick stair climbing because it can generate impulse forces repeatedly at a frequency of 1.25[Hz].

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Infrastructures for human activities e.g. elevators are almost not designed for robots and a telescopic manipulator will be a solution for extending the mobility of robots. We designed a novel telescopic manipulator mechanism which comprises aggregated convex tapes as an arm. The bundling plate is provided with a guiding groove, through which the plurality of convexes pass, to keep the relative position of the plurality of the convexes constant. In this study, we developed a wheel robot with 4 telescopic manipulators and tried to let the robot get on an elevator. The trial is succeeded and our next target will be 3D mobility of the robot in various natural environments.

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Many bridges had been constructed during the steep economic growth age. Presently, dealing with the deterioration of those bridges and maintaining them have become very important. Using robots for the bridge inspection to aim at the labor saving and lowering the cost is hoped for the management and maintenance of many old bridges because the conventional method will intensify the strains on the economy. We had created a four-wheel driving robot for trial purposes that can inspect cracks and corrosion in steel bridge substructures. In this study, we added the improvement to the controller of the robot. We confirmed that the running ability of new robot is better than that of conventional control robot when experiments of running where conducted at right angled routes. Consequently, we found the success method of running.

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This paper shows a comparison of joint based and contact-force based dynamics identification for a 5 degrees of freedom robotic arm. Off-line robot dynamic identification methods are mostly based on using Inverse Dynamics, which calculates the joint torque or contact-force that are linear in relation to dynamic parameters. The estimation of the parameters is carried out using a total least squares or weighted least squares method. However, these methods can identify only the minimal-set of inertial parameters. In this paper we calculate the dynamic parameters in two ways which are joint based and contact-force based and we also calculate the standard parameters closet to a priori consistent dynamic parameters obtained through CAD data given by the robot manufacturer. Then, we compare joint based and contact-force based identification method with experimental data.

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This paper studies stabilization control of a portable three-legged golf swing robot. Proposed robot consists of a motor to rotate a rigid arm and a rigid link as a golf club. The Joint between the arm and the link is the passive joint having a brake mechanism only. When the arm and the link rotate fast, the robot may become unstable and one or two legs may lift up due to the lift force. To make the robot motion stable, an extension actuator is installed in one leg. Mathematical model of the golf swing robot is derived by Lagrange equation and target trajectories of the arm and the link are proposed. Numerical simulation of the swing motion is carried out and validity of the proposed stabilization approach is shown.

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Rapid reacting motions should be needed for robots working in human environments. Preliminary motions are expected to improve speed of such motions. Thus, we investigated preliminary motions in such complex environments. In this investigation, we calculated expected value of minimum time for state transition of a simple robotic arm model. In addition, we compared the value of cyclic motions with stopping as preliminary motions. As a result, we found that stopping states make speed of reacting motions more fast when target states can be predicted enough and cyclic motions may make the speed more fast when it is difficult to predict target states.

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This paper discusses a motion planning method for assembling a ring-shaped elastic part to a cylindrical part by using a dual-arm manipulator. Our proposed planner, first computes a series of key configurations taking the deformation of the object into consideration. Then, we plan the robot's motion connecting each key configuration based on the Covariant Hamiltonian Optimization and Motion Planning (CHOMP) method. We introduce an energy based objective functional that is obtained by adding a term related to the potential energy of the elastic object. This objective functional yields a trajectory where the deformation of the elastic object is minimized. To confirm the validity of the proposed planners, simulation results of a PR2 robot handling a ring-shaped elastic object are shown. We show that our modified motion planner is able to find a feasible trajectory keeping the deformation of the elastic object as small as possible, and that the assembly task is achieved through the proposed planner.

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This paper shows frequency-response characteristics of some variants of Jin et al.'s (2002) Parabolic Sliding Mode Filter (PSMF), which is for removing high-frequency noise from input signals. The results show that some of the variants effectively attenuate high-frequency input signal with producing much smaller phase lag than conventional filters.

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Robots that write characters like human have attracted our attentions. We construct a system that rewrites handwriting characters by employing a ready-made robot. The data of handwritten characters are recorded by using a pen-type haptic interface. Since it takes long time to track a lot of recorded data by the robot arm, the number of data is reduced. However, the features of characters are eliminated if the reference data are reduced more than needs. Therefore, an appropriate rate of reducing data is investigated in questionnaires and experiments.

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In this paper, we propose a method of motion planning with partitioning of hand path on fast path tracking constant hand-speed motion by redundant manipulator. The hand path is partitioned to "difficult part" that is the part of difficult to move by torque limits and joint velocity limits, and "easy part" that is the part of easy to move. In the difficult part, we make motion planning that we have previously proposed, in order to get fast motion with redundant manipulator. In this time, we propose a path planning method on state-space in order to link a initial state and a terminal state that is derived by motion planning on difficult parts. And, we propose a method that gets fast path tracking constant hand-speed motion using motion plannings of easy part and difficult part.

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This paper describes about disturbance observer (DOB)-based predictive functional critical control (PFCC). Generally PFC couldn't handle constraint on controlled output. A few techniques have been proposed but they have each drawback. We propose new control method using critical control for handling constraints. This approach does not increase on-line computational burden. In this paper, we design critical control for disturbance observer based PFC. The effectiveness of the proposed method is checked through an experimental evaluation. Constrains are imposed on the tracking error and controller output.

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This paper addresses a constrained model predictive control (MFC) scheme based on the disturbance observer (DOB) that can handle constraints on the total control input. In a DOB-based MFC scheme, total control input is the sum of the DOB output and MFC output, however, it is not possible to impose constraints on the total input in a conventional DOB-based MFC scheme. We therefore bring a novel concept called time-variant input constraints into our design and construct a useful structure of combined MFC-DOB systems. The proposed DOB-based MFC scheme is applied to a position control problem of a two-link manipulator, and its effectiveness is checked through an experimental evaluation.

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This paper addresses the problem of joint trajectory tracking errors of a manipulator. Specifically, this paper designs a new joint position controller for PA10 manipulator to improve the trajectory tracking performance. First, the tracking performance of a standard PID controller is investigated by experiments. Then, a new controller is designed based on the experimental results. Moreover, parameters of the controller are designed based on a theoretical analysis as well as experimental results.

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