Surface mobility on planetary bodies has enabled nearly two decades of scientifically-rich exploration of the red planet, however not without its challenges. Future exploration will likely demand enhanced mobility to access more challenging terrain. In this paper, we apply resistive force theory (RFT) to a general grouser geometry model, and present simulation results that show the impact of several parameters on draw-bar pull. This work represents initial steps toward optimizing grouser geometry to maximize draw-bar pull, while maintaining ability to traverse rocks of certain geometries and minimizing energy usage per traverse distance. These criteria are of particular importance in power-constrained planetary rovers.

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In recent years, various numerical simulation methods have been applied to vehicle terrain interaction problems. In this study, the formation of periodic ripples under a rigid wheel was investigated within the framework of finite element (FE) analysis. First, the capability of FEM to analyze periodic ripple formation was demonstrated under relatively low slippage. Then, a hypothesis for the generation mechanism of periodic ripples was provided: periodic ripples are formed under conditions in which clear local failure zones occur and soil is translated vertically via wheel shear deformation action. Furthermore, the characteristics of ripple periodicity (i.e. ripple pitch and period) were discussed.

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The traveling performance of off-the-road vehicles, such as construction machinery and exploration rovers, significantly depends on the interaction between the ground and the traveling mechanism, since inelastic ground deformation and frictional sliding phenomena are induced by the vehicle's movement. In this study, the formation of periodic ripples under a rigid wheel was investigated within the framework of finite element (FE) analysis. Especially, it was revealed that ripple formation has an impact on the multi-pass scenario for lightweight small vehicles.

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This paper describes the control method of the semi-active controlled landing gear system for the lunar and planetary lander. The purpose of this paper is to achieve touchdown on uneven terrain without overturning. Damping force control on each landing gear suppress attitude disturbance of lander main body and prevent from its overturning. The control rule of the landing gear damping coefficient of each landing gear for the three-dimensional lander model is shown and it validated in the three-dimensional numerical simulation model. Touchdown simulation executed on rough terrain which reproduced natural terrestrial surface. Especially, touchdown on the incline and touchdown with a lateral residual velocity are tested. The result of simulation indicates that the proposed control rule for the semi-active landing gear is effective to prevent overturning.

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To control shock responses of mechanical structures, Momentum Exchange Impact Dampers (MEIDs) have already been proposed. They have been applied to reduce floor shock vibration and control lunar exploration spacecraft landing. This paper discusses a design methodology which reduces mechanical structures' shock responses. MEIDs are applied to a multi-legged landing gear system. The system consists of a spacecraft body and damper masses. They are connected by springs (MEID springs). The system is fallen on a slope. In this paper, the damper mass is separated to 2 masses. One reduces rotational motion, the other reduces translational motion. The MEID springs are pre-compressed to increase the transferable momentum. They are released after landing on a slope. The effectiveness of the proposed method is verified by simulations.

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Planetary exploration rover has the purpose of direct exploration by moving planet surface. High performance for rough terrain off-road is required. In this paper we propose a new type of planetary rover which has active control mechanism which controls the center of gravity. The concept of the rover is explained and a prototype rover is introduced. Numerical simulation shows how much the rover improves the performance.

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Unmanned Ground Vechiles (UGV) are required to be operated in extreme environment where the UGV should manage its electric power by itself. A typical approach for the power generation in such scenario is to use Solar Array Panels (SAP). However, the power generation with the SAP on the UGV is different from that used for static system relative to the sun such as for house or satellite. This study focuses on a development of the power generation system for the UGV; in particular, the Maximum Power Point Tracker (MPPT), a core device in the power generation system is developed. Three tracking methods were implemented in the MPPT and each of them was experimentally evaluated.

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This paper presents that the skyline matching algorithm with considering camera tilt. Skyline matching is the method that estimating position and attitude by comparing two skylines. One skyline is simulated one from a digital elevation model (DEM). The other one is gotten from camera images taking around view. We conducted field experiments in Oshima Island. As a result, we conclude that considering camera tilt has a significant influence.

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Self-localization is one of the key techniques in remote mobile robot. Visual Odometry for calculating the amount of movement of the robot by using the camera image among them are commonly used. However, it is possible to predict the search position in the Land Mark of the next frame, it is not taken into account until the range. In this paper, it is an object of the present invention that the long-term environmental measurement by utilizing the Land Mark search range control, and the reference plane by statistical existence probability.

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In this study, we proposed a new mobility device using tether under the microgravity named Tether Space mobility Device (TSMD). TSMD is the mobility device that moves user by winding tether which is attached to the structure in the destination. We focused on winding of tether and proposed the posture control method of TSMD which combined with the winding control and the arm control, the experiment in the two-dimensional microgravity environment is performed. As a result of the experiment, it is confirmed that the proposed control methods decrease rotational motion, and it is found that they makes it possible to control posture of the system.

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This paper proposes a vibration suppression control using a tether in SSPS. We prepare the numerical calculation model which simulates the panel surface of the SSPS and verify experimentally that model's validity. And we investigated the state of vibration of the cantilever which is connected to the tether. It also propose to use a PVDF as a sensor. As a basic research, to ascertain the PVDF can sense the vibration.

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We propose that a sampling device with a cylindrical corer for the acquisition of surface samples be used to penetrate in a primitive body exploration mission. The system's penetration mechanism would consist of a circular tube with a thin wall. Based on past experimental studies, we can assume that the device's penetration depth would be proportional to its mass and velocity to the 1.5 power. (This is designated as effectiveness). An analysis of the penetration angle's effect on the device's penetration coefficient has already been carried out by defining the term penetration performance, which accounts for the device's performance coefficient (Cp), a dimensionless quantity of the depth, and the angle of attack, α, the angle between the velocity and attitude vectors during penetration. Furthermore, α has been defined as equivalent to hasuji-the orbit at the edge of a sword in Japanese martial arts-which is known to affect cutting abilities greatly. We therefore analyzed the cutting motion of Japanese swords using a high-speed camera and applied the results to the proposed corer's design to improve its performance.

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The rational treatment of frictional interaction between lunar soil and mechanical system is one of technical issues in lunar operations. This reason is that the evaluation method for frictional interaction in lunar surface environment, for example, heavily over-consolidated soil, soft grand, low gravity and high vacuum condition. In this study, first, we performed the rotational shear test of granular media using test apparatus. Then, we combined a magnetic field device with the test apparatus in order to investigate the effect of gravity on frictional interaction. By using the test apparatus, we can perform the test under a pseudo low gravity condition in which the gravity is adjusted at 1.0 and 0.75G As a result, the effect of gravity on frictional interaction when gravitational field is 0.75G was hardly confirmed. This conclusion is also confirmed by analyzing using discrete element method.

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Recently, it has been required agile control of satellites. For this purpose, the necessity of Control Moment Gyros (CMGs) has been increasing, which can generate much more torques. However, CMGs have a singularity problem. At singularities, the torque generated by the CMGs degenerates from three dimensions to two dimensions in the case of a specific set of angular momentum and angle of gimbals, and it may affect spacecraft attitude control performance. This study proposes a new steering control law for variable-speed control moment gyros (VSCMGs) designed for considering singular direction and maneuver direction using singular value decomposition. The proposed method is able to escape singularities more agile to change a specific set of angular momentum of gimbals.

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In this paper, we propose an improved adaptive trajectory tracking control scheme for wheeled mobile robots without using velocity measurement. At first, a modified tracking error equation is developed. Based on the modified tracking error equation, a modified adaptive tracking controller is developed. The developed controller does not require measurements of longitudinal velocity. In the control system using the controller, robust tracking control can be achieved for uncertainties of the weight, the moment of inertial and the position of gravity center. In addition, even if the characteristics of left and right motors to drive wheels are unknown and different, stable tracking control can be also achieved.

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This paper deals with a new Two-Wheeled Flying Robot traveling a slope. This paper considers the problem of controlling the position of the robot traveling a slope. The robot is described by a set of nonlinear equations. This paper presents a new adaptive controller based on Input-Output linearization for position tracking in slope traveling. A numerical simulation is performed to evaluate the effectiveness of the proposed controller.

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Recently, highly energy efficient products have become more and more valuable. However, in hydraulic excavators, saving energy sometimes causes hunting. Here, excavators have Pressure-Displacement Capacity Control (P-Q Control). The purpose of this study is designing a control system to suppress hunting with highly efficient. In this paper, the hydraulic system is first modeled to clarify the reason of hunting, and P-Q Control is changed for PID control which can compensate delay time. Furthermore, PID parameters are determined based on closed loop data. To calculate PID parameters without simulator, modeling error is excluded.

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This paper considers a new tracking control problem for a four-wheeled vehicle robot. The robot is a nonholonomic system described by a set of nonlinear equations and some parameters of the dynamics are uncertainties. In this paper, an adaptive practical tracking control method is proposed, and the tracking control problem of the robot system is reduced to that of a simple linear system. Accordingly, the controller design method is simple and straightforward. The obtained controller can reduce the tracking error less man or equal to any specified positive value for a given desired trajectory asymptotically. Moreover, a new and useful design method on the upper band of the tracking error is presented based on the curvature of the desired trajectory. Some numerical simulations are performed to evaluate the effectiveness of proposed controllers.

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In this paper, we propose a method of a path-planning for a mobile robot. The method uses a grid map to define any shape of obstacles and considers shape of mobile robot. The shortest path can be generated by searching the grid map. This method consists of two steps to expand obstacles, and can provide practical and suitable path-planning for a control of a mobile robot. Moreover, the path-planning can set arbitrary start posture and end one. The effectiveness of this method is shown by simulation.

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In the development of the aging society, it is important for patients with hemiplegia to introduce the adaptive welfare equipment. However, it is difficult to support them by using general welfare equipment because there are a lot of individual disabilities. Therefore, the adaptive welfare equipment is needed in near future. In this study, 1-parameter tuning which is one of the self-tuning control scheme in the process industries, is applied to a welfare equipment. Simulation results are provided to demonstrate the effectiveness of the proposed control scheme.

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In the paper, we develop an adaptive tracking controller scheme for multirotor helicopter with unknown thrust and drag coefficients. At first, by using an unknown positive definite matrix and an unknown triangular matrix, we decompose the high frequency gain matrix in a tracking error equation. Next, based on the new tracking error equation, an adaptive tracking controller is developed. The developed controller does not require accurate values of the weight, moment of inertial of multi-copter, and the thrust and drag coefficients are also not required. Finally, to confirm the usefulness of the proposed controller, numerical simulations are carried out.

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In this paper, we deal with an adaptive trajectory tracking control system design scheme for a quadrotor. ASPR based high gain adaptive output feedback strategy will be applied to design a trajectory tracking control of a quadrotor by introducing an inner-loop PFC so as to guarantee the ASPRness of the quadrotor. The proposed method can design a relatively simple controller by introducing a PFC for a quadrotor inner-loop model. The stability of the obtained adaptive tracking system will also be analyzed and the effectiveness of the proposed method will be confirmed through numerical simulations.

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The main task of product development is to develop a good product at lower cost and to bring it to market in a shorter period. Conventional computer-aided design and computer-aided engineering (CAD/CAE) systems are well established in this regard. However, although upstream design is particularly important in product development to add value and incorporate the required functions, it is difficult to apply conventional shape-based CAD/CAE systems to the upstream design stage due to the lack of design information at that stage. As a solution to this issue, we are proposing the development of a design framework called "1DCAE," which can be applied to the early design stage of product development including the conceptual and functional design phases. The 1DCAE concept can be applied not only better design, must design, but DELIGHT design. Here we introduce how 1DCAE concept applies to delight design and its core technology of KANSEI modeling.

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In this paper we describe a system model to clarify the relationship among frequency transfer characteristics and the design parameters. By using SysML (Systems Modeling Language) the system architecture of a mirrorless interchangeable-lens camera is modeled from the view point of its shutter sound. Parameters affect the frequency transfer functions from inputs to outputs of each component constructs the system are clarified from the parametric diagram, while the activity diagram shows the resonance generated in the cavity from the propagated sound waves of different two components

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For the effective system development, it is important to consider the system model with high level of abstraction derived by analyzing system requirements and its functions from the early phase of the development. Through the requirement analysis and functional architecting, trade off analysis and evaluation is performed. In this paper, validating the system model utilizing 1DCAE is discussed. As for example, a system model and a simulation model of a control system for a motorcycle are derived and validated based on system analysis using SysML (System Modeling Language).

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A system design problem of an automatic harvester of spinach is considered in the present paper. It is required to consider for an agricultural automatic harvester for soft leaf vegetable not only specifications of a mechanical system but also ones of the cultivated land and tuning before shipping. In the present paper, decision of specifications of an automatic harvester of spinach is described and a result of design is shown.

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This paper shows a design method for a PI-D controller's gains which is utilized for driving active mass dampers using a neural oscillator. In the system, the output of the neural oscillator synchronized with structure responses is not only used as a rhythmic command, but also used to decide the desired value of the auxiliary mass. In addition, in order to drive the auxiliary mass to the desired value, the position control system consisting of a PI-D controller is used. In our previous study, the design method for PD gains as the position controller has been discussed. However, it is not practicable that using only P and D gain, because the rapid acceleration was happened when the driving direction of the auxiliary mass changed. Thus, in this paper, to moderate the acceleration response of the structure, the PI-D controller having I gain is used instead of the PD controller. Additionally, the design method of the PID controller is also discussed from a vibration control point of view. As a result of the numerical simulation shaken by earthquake, it was clear that the system using PI-D controller provided better effects for structural vibration mitigation than the system using P-D controller.

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We have been working on design of a new unique control system for active mass dampers, which consisted of a neural oscillator and position controller. In the system, the output of the neural oscillator synchronized with structure responses is not only used as a rhythmic command, but also used to decide the desired value of the auxiliary mass. In addition, in order to move the auxiliary mass to the desire value, the position control system consisting of a PID controller is used. In previous study, the auxiliary mass' stroke is decided by using the Phase and Amplitude MAP (PAMAP) including contours. However the desired value of the auxiliary mass was discontinuity depending on the division number of the contours, and the algorism using PAMAP was not so easy to handle. Thus, this paper proposes the method to decide the desired value of auxiliary mass without PAMAP. Specifically, for deciding the stroke of the auxiliary mass, the simple four rules of arithmetic of neural oscillator's state quantities is operated in this method. As a result of numerical simulation, when the structure was quaked by earthquakes, the structural vibration was reduced by the effect of the auxiliary mass' motion and the proposed system had similar ability as the active mass damper designed by the LQ theorem.

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This paper discusses seismic response control of high-rise building utilizing magneto-rheological fluid damper (MR damper). For high-rise building, bending displacement of whole system due to column elongation cannot be neglected. To simulate the behavior of a high-rise building during an earthquake, one-mass system consisting of a cantilever column and a spring to limit the top rotation has been prepared for this feasible study. A MR damper has been set into the vertical direction to control rotational motions of the system. The MR damper can change damping force according to exciting current. ON/OFF control method for input current is investigated in this study. Through shaking table tests, it is cleared that proposed control method can effectively reduce the acceleration response of high-rise system.

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A new response control mechanism, which is composed of frames equipped with passive dampers and hardening elements with gaps, is proposed. Using this mechanism, the frames response as usual vibration controlled systems within expected amplitude levels, and they show full capacities against unexpectedly large earthquake ground motions, by changing their vibration modes. The authors demonstrate the effectiveness of the system by conducting response analyses of a multi-degree-of-freedom model. And they also reported a loading test results of scaled frames equipped with the proposed system.

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The objective of this paper is to disclose a limitaion of response spectrum method for maximum earthquake response of connected vibration control structures. In general, higher mode with very large damping factor such as over 40% can be ignored in response spectrum method for maximum earthquake response. However, natural mode with over 100% damping factor (i.e., overdamped mode) of connected vibration control structures sometimes plays a significant role in maximum earthquake response. Simple index of predominance factor of overdamped mode in maximum earthquake response is proposed and a contour map of the index is shown in mass ratio - stiffness ratio plane. The reason why over damped mode of connected vibration control structures sometimes plays a significant role in maximum earthquake response is illustrated with complex natural modes.

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The objective of this paper is to disclose reduction effects on maximum deformation of base isolation story and maximum acceleration of top story of a base isolation structure by introducing a second isolation story with nonlinear restoring force-deformation relationship into mid story of the structure. The structure with base isolation story and second isolation story into mid story is called as "a multiple isolation structure" in this paper. It is shown that the response reduction effects in multiple isolation structure tend to become large when the second branch of story stiffness of second isolation story becomes small through time-history analyses to recorded earthquake ground motions.

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The dynamic characteristics of mid-story isolated buildings and seismic response reduction due to a semi-active control system were investigated using a three-lumped-mass model that simplified the sixteen story building with an isolation layer in the sixth story and that model. A semi-active control method using a rotary inertia mass damper filled with magnetorheological fluid (MR fluid) was proposed. The damper shows both mass amplification effect due to rotational inertia and variable damping effect due to the MR fluid. The damping force is controlled by the strength of the magnetic field that is applied to the MR fluid. It is determined by using the electric current, which is calculated by the proposed semi-active control method based on the velocity of the isolation layer relative to the layer just underneath it. Real-time hybrid tests using an actual damper and simulations using a building model were conducted to check the damper model; the test results were in good agreement with the simulation results. The simulation results suggest that the response displacement of the structure above the isolation layer is significantly reduced, without increasing the response acceleration of the entire structure against near-fault pulse and long-period ground motions. The proposed semi-active control using an MR rotary inertia mass damper was confirmed to be effective for mid-story isolated buildings.

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In this paper, a novel combination of structures for connected-control mechanism (CCM) is presented. By coupling base-isolation and ordinary structures, the vibration suppression effect of CCM is expected to be expanded, while the stroke of base-isolation layer is hopefully suppressed. Experimental structures and CCM mechanism using magnetic dampers are built andexcitation experiments are carried out. The effects of the numbers and locations of the dampers are examined. In study, spring elements are added to obtain further vibration suppression effect. Excitation experiments are carried out

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Liquid packaging machine processes fast moving plastic film and produces liquid packaging bags continuously. The machines use rotary tools and coordinated velocity control of them. Two control schemes have been applied to produce arbitral size of bags. One is two-steps velocity control of the seal roll and second is a synchronous motion control of seal roll and cut roll. Previous machines employed programmed velocity pattern and the motion controller to achieve the pattern precisely. This paper proposes a simple control system, which switches the velocity command of the motor driver by using a positioning dog attached at a roll axis. The control system adjusts the high or low feed speed command according to the angles of feed roll based on the feedback control schemes. In order to examine the practical problems, a simple film processing machine was developed and experimental results using the machine shows that the proposed control system can be applied to actual machines.

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This paper deals with the control system design for active isolation table. If elastic loads are put on the isolation table, vibration modes of the table are changed. Therefore, the controllers for the active isolation table should be designed taking account of elastic loads. According to this fact, a dynamical model must be identified that takes the dynamics of elastic loads into consideration for such controllers. In this research, an experimental active isolation table with an elastic load is built. Its dynamical model is identified by using experimental modal analysis or FEM analysis. Three controllers are designed by using the model according to sub-optimal control theory, absolute velocity feed-back control theory and feed-forward control theory, respectively Property of the obtained controller's are qualified through computer simulations and control experiments.

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The control performance of the FPD (Flat Panel Display) exposure apparatus plays an important role to improve the performance and productivity of the liquid crystal panel, and the stage in the apparatus must be control with high speed and high precision. However, the control performance is deteriorated due to the influence of a coupling effect between axes when the stage is moved at a high speed. This paper proposes a design method taking account of the interference between axes using a gain scheduled LQ. The effectiveness of the proposed method is verified by simulations.

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This report is concerned with discrete-time systems that are derived for two dimensional continuous-time LTI systems by the pulse-width-modulation input. Although the input term of the discrete-time system is a nonlinear map of the duty ratio of the rectangular wave, it can be exactly linearized by varying the center of each rectangular waves as well as its duty ratio. In this report, this novel method is applied to two physical systems, that is, a rotating system with thrusters and an inverter circuit, to systematically design control laws.

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In many positioning control systems, the completion of the positioning phase must be determined correctly in order to initiate the start of the next task. However, it is not easy because the output may exceed the allowable error bound again. For this problem, we have proposed a method based on a support vector machine (SVM). The effectiveness of the proposed method has been verified by simulation and experiment using a simple plant model, however, it has not been evaluated for actual industrial systems which require severe control performance. In this paper, the proposed method is applied to the positioning control of a galvano scanner, which is the important component of the laser processing systems, and the effectiveness is evaluated by using experimental data.

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Previous studies of semi-active vibration control methods using piezoelectric actuators and inductors mainly focus on vibration suppression of force excitation systems and free vibration systems. In general, appropriate control for these systems is increasing the damping of the structures. The increase of the damping is achieved by not only the control methods but also passive damping materials. Therefore, the merit of using the control methods is not clear, except for applications in extreme conditions which do not allow usage of passive damping materials. In contrast to these systems, active and semi-active methods generally have advantages over passive damping materials in vibration isolation of base excitation systems. Passive damping materials can not suppress both resonance response and transmissibility in frequency range higher than resonance frequency simultaneously. In this paper, one of the semi-active methods is applied to vibration isolation of a base excitation system. The numerical simulations of the system show that the semi-active method can suppress resonance response without increasing transmissibility in higher frequency range.

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Robots with torque sensors exhibit flexibility in joint action. Flexibility, however, causes some problems in the motion control. For example, the model becomes more complicated. Vibration of the end-effector is also one of serious problems. We propose a control method to suppress the vibration of flexible robots by means of a simple model with a notched filter. In this paper, our proposed method was verified by computer simulation and operation tests.

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