Navigating unknown three-dimensional (3D) rugged environments is challenging for multi-robot systems. Traditional discrete systems struggle with rough terrain due to limited individual mobility, while modular systems—where rigid, controllable constraints link robot units—improve traversal but suffer from high control complexity and reduced flexibility. To address these limitations, we propose the Multi-Robot System with Controllable Weak Constraints (MRS-CWC), where robot units are connected by constraints with dynamically adjustable stiffness. This adaptive mechanism softens or stiffens in real time during environmental interactions, ensuring a balance between flexibility and mobility. We formulate the system’s dynamics and control model and evaluate MRS-CWC against six baseline methods and an ablation variant in a benchmark dataset with 100 different simulation terrains. Results show that MRS-CWC achieves the highest navigation completion rate and ranks second in success rate, efficiency, and energy cost in the highly rugged terrain group, outperforming all baseline methods without relying on environmental modeling, path planning, or complex control. Even where MRS-CWC ranks second, its performance is only slightly behind a more complex ablation variant with environmental modeling and path planning. Finally, we develop a physical prototype and validate its feasibility in a constructed rugged environment. For videos, simulation benchmarks, and code, please visit https://wyd0817.github.io/project-mrs-cwc/.

In the field of robotics, researches have sought to control robots capable of dealing with a variety of environments and tasks generically, through the use of foundation models. Among these, the systems for robot behavior planning utilizing video have also been proposed. The system enables the generation of robot behaviors that are not dependent on specific environments or tasks. This is achieved by generating videos based on text input, which utilizes the vast knowledge inherent in the foundation models. Also, by using a visual interface such as video, it is possible to confirm the behavioral indicators on which the robot is operating. Although, there are few examples of research on robot behavior planning utilizing video. Previous studies have emphasized the verification of behavior generation utilizing video, with simplified object manipulation for testing on simulations. This is not enough to demonstrate the usefulness of robot behavior planning utilizing video in real-world environments. In addition, the systems from previous studies are not open, and such systems have not been sufficiently discussed. This paper attempts to construct robot behavior planning utilizing video as an open system, and to verify the validity of the behavior planning using actual machines. In this paper, we first focus on using Robotis's TURTLEBOT3 Waffle Pi and Mobile Manipulator(referred to as "Waffle") to construct robot behavior planning system utilizing video. Second, we create planning videos targeting the pick-and-place motion using the proposed system, and control the arm part of Waffle in the actual machine verification. Finally, by comparing the target coordinates from the planning video with the coordinates observed from the actual machine, we can confirm whether it is possible to control Waffle as planned. Errors are calculated from the coordinate comparison, and the control is performed again. Based on the results, we verify whether the proposed system is useful for controlling robots in real-world environments.

A system is expected to facilitate coordination among multiple construction machines or robots, enabling them to adaptively perform various tasks in disaster sites and unknown environments. Prior research has generally adopted a model-based approach to designing cooperative behavior. However, it is difficult to adapt to environments and scenarios that cannot be predicted by the model. In recent years, it has been reported that a robot equipped with foundation models can adapt to unknown (open) environments and unpredictable situations. However, there has been little discussion on foundation models for multiple robot systems; a flow that cooperatively handles unexpected events does not exist. In this paper, we propose the system flow that enables multiple robots to adaptively coordinate to unforeseen scenarios based on the functional expressions of each other and environment understanding utilizing GPT-4 and GPT-4V. Through experimentation, we verify that the proposed flow is able to adapt to an unforeseen environment, particularly path obstruction via robot experiments. Furthermore, we examine the validity of the proposed flow by varying the robots’ functional expressions and sensor information for the environment.

In this paper, we propose a new kind of tripedal locomotion-namely, robotic walking with three legs. We develop a prototype robot, which we call Martian III, having three stretchable legs fixed to each other at the center of the body. Therefore the coxa (the hip joint) is completely fixed in this robot, and the only control we have are the linear actuators to stretch the three legs in the radial directions. The robot is developed as a minimal model to examine our basic idea, to make the robot swing by actuating the legs and then generate locomotion utilizing geometric effect of rigid body rolling on a flat floor. The experiments with robot succeeds in forwarding and rotary locomotion with appropriate choices of oscillatory along each leg. Further analysis of the movement of Martian III indicates that the direction of the swing leg depends on the deformation of each leg. Moreover, due to the result of the measurement experiment and movement analysis of rotation locomotion, we found out two typical type of gaits.

Cylinders exhibits characteristic dynamic behavior such as rolling with lateral-side or edges. In this paper, we propose a new type of rolling mobile robot with cylindrical aspect, which performs two contrastive modes of motion due to the geometry of its shape. In the first mode called lateral-side rolling, the robot is statically stable except few degree of freedom, whereas the robot is only dynamically stable in the other mode (called edge-rolling) and has potential of high mobility. In this work, we attempt to control this robot using an eccentric rotor without gyroscope and applying linear or nonlinear control theory.

This paper is concerned with realization of a new kind of three-legged walking machine. The proposed robot has neither coxa joint nor knee joint, so the three legs are just rigidly fixed to each other. Instead of pursuing elaborated joint mechanism for the coxa, we equipped it with two actuators and a pair of weights, so that it can generate torque about the yaw and the pitch axes. Thus it only rocks as a reaction of the mass driving unit. We show that, by appropriate choices of oscillatory controls (i.e., amplitudes, frequencies and phases of the pitch and the yaw actuators), it is indeed possible to achieve rotation and forwarding locomotion of the tripedal robot. In particular, combination of the frequencies selects the rotation/forwarding, while combination of the phases affects the direction of forwarding. We also remark that the realized motion naturally reflects the symmetry of the body structure.

Much attention has been paid to passive dynamic walking as an approach to investigate the walking of human beings and animals. As for quadrupedal passive dynamic walking, it is confirmed that walking resembles that of animals, and that the gait of the robot changes depending on the structure of robot or the environment. Based on these facts, it is conceivable that quadrupedal passive dynamic walking is related to walking of animals, and the walking principle is inherent in passive dynamic walking. In this research, we approach the walking principle through realization of a walking on the level ground by rational-energy input and investigation how gait changes depending on the input. In this paper, a quadrupedal quasi-passive dynamic walking robot named Duke has been developed by applying passive dynamic walking. This robot has only two rolling actuators, which simply provide with rocking motion and not drive the knee or hip joint directly. We conduct walking experiments by Duke with various inputs, and observe its gaits. As a result of walking experiments, it was verified that walking speed was related to the frequency and the phase difference of rocking motion. In addition, through analysis of a shape of soles, we revealed Duke has a nonholonomic constraint that is comparable to that of “two-wheeled robot” on its sole. As a result of analyses based on the nonlinear control theory, we conclude that the sole shape contributes to the transition of walking speed accompanying with change of a phase difference.

Human is capable of adaptive and supple locomotion in the real world characterized by rapid changes, high uncertainly, and limited availability of information. In order to understand the human walking, this work was motivated by the concept of passive dynamic walking robots, which have no actuation or control system except for gravity are capable of stable, human-looking walking. On the other hand, human can produce a stepping motion not only depend on the legs, but also the rotation of the Center of Mass, arm-swing, the motion of the torso and so on. In this paper, a three dimensional quasi-passive dynamic walking provoked by rocking motion in lateral plane has been investigated. The behavioral analyses with the robot experiments show that this robot can walk on a flat ground and a gait speed is related to the period of lateral rocking.

A Sarin gas attack occurred in the Tokyo subway system on March 20, 1995. This fatal gas attack sickened many passengers. Since the disaster broke out underground, the main job of the rescue personnel was to transport victims on stretchers to a first-aid station above the ground. Therefore, we researched the development of a rescue support stretcher system for handling heavy casualties in underground areas or at stations in a quick and effective manner. The stretcher system is expected to help firefighters achieve efficient rescue operations. In this paper, we introduce a rescue support stretcher system for going up and down stairs. We also propose an upgrade technique. Finally, we experimentally examine the effectiveness of the system.

A robot driven by a McKibben pneumatic actuator generates stable motion despite its simple control and simple actuator model. However, how its characteristics act on the stability of robot motion have not been sufficiently discussed. In this paper, a model of the McKibben pneumatic actuator is derived in which the actuator characteristics are considered. In modeling the McKibben pneumatic actuator, we concentrated on its dynamic characteristics.We applied the actuator model to a simple robot model and analyzed the stability of the motions generated by the actuators. From the stability analysis results, we found that the stability of the constant posture is satisfied by the static and dynamic characteristics of the McKibben pneumatic actuator.

In this paper, we propose an idea which can solve the complexity of the overlapping situation observed in control system of living things. We introduce an another element between controlled object and control law. This newly introduced element is named as Implicit Control Law and decided by interaction of the controlled object, the control law and the field. Furthermore, the Implicit Control Law does not only solve the indivisibility problem but also produces a start point for understanding of realtime environmental adaptation function of living thing with tiny brain. That is, the Implicit Control Law is a core principle of Mobiligence.

It is well known that a robot driven by a McKibben pneumatic actuator generates stable motion in spite of its simple control and simple actuator model. However, how the characteristics of the McKibben pneumatic actuator act on the stability of a robots motion has not been sufficiently discussed. In this paper, a physical model of the McKibben pneumatic actuator is derived and the stability of a robot which is driven by the McKibben pneumatic actuator is analyzed.

The research of image-based control for nonholonomic mobile robots is a recent topic of mobile robots. There are few researches about image-based control of mobile robots with central catadioptric cameras. A central catadioptric camera is very effective to keep target objects in the camera field of view because of its wide area view. In this paper, a new image-based path following control method for a nonholonomic mobile robot with a central catadioptric camera is proposed in the image parameter space. It is confirmed by several simulation, indoor and outdoor experiments that the designed system has high performance and robustness in real world.

We propose a new framework for a self-propelled flexible cable in which the freedom of lateral motion with sliding movements is increased on the basis of simple shape information.We developed a large-scale prototype of the flexible cable that has a ciliary drive mechanism and precise shape sensors to investigate our concept.We developed a kinetic model for the prototype by employing the nonlinear driving force model and the lateral friction model for representing slippages. Further, we proposed a sliding motion control method that focus on the shape and length of the straight element. We applied the method to control the running direction. The experimental results and dynamic simulations demonstrated the effectiveness of sliding motion for controlling the running direction.

In this study, we discuss the common stabilization mechanism underlying passive dynamic walking (PDW) and passive dynamic running (PDR), focusing on the feedback structures in analytical Poincare¿ maps. To this end, we have derived linearized analytical Poincare¿ maps for PDW and PDR, and analyzed these stabilities on two models, namely models with elastic elements and with stiff legs. Through our theoretical analysis, we have found an ¿implicit two-delay feedback structure¿, which can be seen as a certain type of two-delay input digital feedback control developed as an artificial control structure in the field of control theory, is an inherent stabilization mechanism in PDR appearing from the model with elastic elements, and two-period and four-period PDW appearing from with stiff legs. This mechanism is the key to adaptive function underlying phase transition phenomenon between PDW and PDR and period-doubling bifurcation phenomenon in PDW. To the best of our knowledge, this has not yet to be addressed and studied so far. Our results shed new light on the common underlying principle of passive dynamic locomotion, including biped PDW and PDR.

The control and mechanical systems of an embodied agent should be tightly coupled so as to emerge useful functionalities such as adaptivity. This indicates that the mechanical system as well as the control system should be responsible for a certain amount of “computation” for generating the behavior. However, there still leaves much to be understood about to what extent “computational offloading” from the control system to the mechanical system should be achieved. In order to effectively consider this, here we particularly focus on a passive dynamic running biped whose behavior is generated purely from its mechanical system, and investigate how the body’s properties influence the resulting behavior. Through the numerical simulations, we have found that two elastic parameters of its body, leg spring constant and hip coil spring constant, play a crucial role, and depending on which various kinds of stable gait patterns are generated. To the best of our knowledge, this has not been explicitly addressed so far. The results obtained are expected to shed a new light on to what extent the mechanical system should be responsible for generating the behavior.

In the past decade, search robots in rescue operations have been focused on and developed for the purpose of finding survivors trapped in the rubble of collapsed buildings. Most of them adopt serpentine mechanisms: they comprise of track-equipped segments that are connected by joints to obtain greater mobility in extremely complex environments. However, they might gather to catch debris between tracks or become stuck due to the mechanisms, in addition, increasing the number of segments would result in gaining weight and complicated mechanism and control system. In this paper, a new mobile mechanism: flexible mono-tread mobile track is proposed and a prototype ldquoRescue mobile track No.2 (RT-02) WORMYrdquo is developed. The vehicle is composed of a ldquoflexible chainrdquo and a spine-like structure. It is examined on mobility performance in irregular environments.

The purpose of this paper is to analyze the stability of Passive Dynamic Walking (PDW) using a linearized analytical Poincare map. In particular, in this paper, we focus on a bifurcation phenomenon in PDW. Although the bifurcation of the walking period is one of the well-known features of PDW, it have not been studied sufficiently so far. Using techniques similar to our previous research, we derive an analytical Poincare map for 2-period walking and discuss the stability of PDW with this map. In addition, we point out that there is a similar interesting structure in this Poincare map.

This paper gives an exact and explicit expression of the structured singular value for robotic manipulators with a passivity based control in port-controlled Hamiltonian form, even though it is not possible to give the exact or explicit structured singular value for general systems. First, we focus on dynamics with endlink mass perturbation after the settling time. Second, we derive the exact and explicit structured singular value for manipulators by using structural properties of the dynamics. The derived structured singular value is nothing but the structured singular value of manipulators without control because the passivity based control preserves the Hamiltonian structure. Furthermore, based on the derived structured singular value, we quantitatively analyze the robust stability of robotic manipulators with the passivity based control

We propose a new active vision of a heavy material handling agricultural robot emphasizing the initial cost. A key point is a new combination of a structure system and a control system, not only one of the two. First, a camera configuration with only one camera is proposed to achieve lower initial cost. This configuration requires more robustness. Second, in order to realize the vision, a robust control system is designed in the presence of uncertainty and constraint. Finally, the validity is confirmed by experiments in an actual open field. The camera configuration can not work well without the designed controllers. That is, the robust controllers reduce the initial cost.

This research project, as a part of special project for earthquake disaster mitigation in urban areas initiated by the MEXT, aims to extend the existing robotics and human interface technologies and to establish a novel human-machine interacting structure to enable effective use of semi-autonomous robots in place of humans for searching survivors from rubble under human remote instructions. Collaboration and coordination of the human and robot intelligence and skills are to be developed from both hardware and software viewpoints to make the results of this project contribute to improvement of the search technology, an important issue in the urban robot-assisted search and rescue activities. Research efforts and results are described in this paper.

This paper proposes a new type of output coupling mechanisms using the harmonic drive. The mechanism uses the input surplus power through distributing it to the other outputs, which enables us to use the input power more effectively. The proposing mechanism has ability of speed reduction and non-backlash anew. We can keep the increase of torque loss and inertia to a minimum because we can put together output coupling mechanisms and reduction gears. We express in this paper about a compositional principle of this mechanism and experimental results. And we show the effectiveness of this mechanism.

Global performance of agricultural robots is discussed to design the structure system reasonably. First, problems of the theoretical field capacity are summarized. Then a new macroscopic working environmental model is proposed. Third, the theoretical field capacity is extended to solve the problems based on two fundamental equations of working space and working time. Finally the validity of the extended theoretical field capacity is confirmed by deriving two design guidelines for structure systems of agricultural robots.

An experimental study is presented on control of a heavy material handling agricultural manipulator using robust control. The harvesting of heavy vegetables and organic compost fertilization requires hard manual labor. For heavy material handling, an agricultural robot was proposed in the first step. And then a control system using LQ control was designed and high-speed manipulation was realized in the second step. In this paper, we designed a control system to achieve robust performance in the presence of uncertainty. The robotic harvesting experiment was done in the watermelon field and the use of robust gain scheduling and /spl mu/-synthesis was confirmed.

Concepts and necessity of a dummy (human model) which can simulate a disaster victim for the purpose of evaluating rescue equipments including robots and rescue skills of human and robots are proposed. By contrast of conventional dummies in various fields, the concrete requirements are made clear. The plan of research and development project based on the concept is described. In the latter part of this paper, the 1st prototype under development is introduced. It is based on a human model (doll) for training of bathing assistance, and is equipped with 8-channel telemetric sensors, a wireless camera, a voice recorder, a heater vest, and a carbon dioxide gas tank.

In this paper we introduce our developed prototype mobile inspection robot for rescue activities named MOIRA. The robot consists of multi links and the four directions of each link are equipped with small crawlers. Due to the structural features, MOIRA has the following features. (a) MOIRA can go into the debris even if there is a restraint from the four directions (up-side, down-side, right-side and left side). (b) MOIRA does not have a concept of the four directions. That is, MOIRA can be operated even if the robot sideslips without any recover actions.

In this paper, we introduce a new control method of quasi-passive dynamic walking for a biped walking robot. The control low uses actuators just only to maintain the passive walking. First, focusing on the contact phase of swing leg, the stability analysis of passive walking robot is performed through a discrete-time system of the robot. Second, we propose a new control method of semi-passive walking based on delayed feedback control, which do not require any reference trajectory for walking. Finally, the effectiveness of the control law is shown through several simulations.

For heavy material handling, we first propose an agricultural robot which consists of a 4-DOF underactuated manipulator, a crawler vehicle, and a passive hand in the first step. Then, we discuss the use of LQ control for high speed manipulation. We design a control system based on the characteristics of agricultural operations and the manipulator. The robust stability is analyzed under the structured uncertainty. The robotic harvesting experiment was done in a watermelon field and the effectiveness of LQ control was confirmed.

Since there are many high-rise condominiums, ladder tracks are used against high-rise building fire. However, their height is much higher than the reachable height of the ladders. On the other hand, there have been some studies of vertically moving robots by means of suckers on walls. However, their climbing speed and reliability are not enough for use in an actual fire fighting operation. Therefore, we propose a vertically moving robot which utilizes a balcony handrail as a step. We designed and made a full-size trial robot. We built up the dynamic model of the robot, and planned desired trajectories for the robot. Furthermore we designed a hybrid control system that consists of nonlinear feedback and a sequential method. We concluded that the vertically moving robot is useful for fire fighting against high-rise condominiums from the results of experiments.

The Japanese Government plans to hold the International Robot Games Festival in 2001, which is called "RoboFesta 2001". The RoboFesta 2001 will be held both in the Osaka area and Kanagawa Prefecture in Japan, and will consist of several authoritative robot games, an international forum, and lots of robot-related exhibitions during the summer and autumn in 2001. The article describes the aims and organisation of the festival, then describes the various games.

In this paper, passive walking of the eight-legged robot QUARTET II that has simple straight legs, and is also constrained to have two degrees of freedom for the simplicity of its motion, is described. The legged robot can continue to walk down a slight slope steadily without any actuation if appropriate initial conditions are given. Since no control input, except for gravitational torque, is applied to the robot, more natural gaits compared with those of conventional actuated walking robots are expected. In walking simulation, trajectory stability and bifurcation that occurs along with the increase of slope angle and finally leads to chaotic gait are discussed. In walking experiment, some kind of trajectory stability and bifurcation can be observed.

Disaster rescue is one of the most serious social issues which involves very large numbers of heterogenous agents in the hostile environment. The intention of the RoboCup Rescue project is to promote research and development in this socially significant domain by creating a standard simulator and forum for researchers and practitioners. While the rescue domain is intuitively appealing as a large scale multi-agent domain, it has not yet been given thorough analysis of its domain characteristics. We present detailed analysis of the task domain, challenges, and outline benchmark evaluations.

In this note, we consider natural disasters and protection against disasters. Then, we discuss rescue activities from a viewpoint of robotics, and consider the development of a new field of engineering, rescue engineering.

We introduce a newly developed legged robot QUARTET III. Two direct drive motors are mounted on the robot as a main actuator. Therefore, this robot can walk both actively and passively. We also propose a new control law for the robot on a slight slope. The strategy of the control scheme is as follows. At the beginning of the walking, the robot walks with actuator. Then after a while the control input gradually decrease. Finally, the robot walks passively. The effectiveness of the control law is shown through simulations and experiments.

The Great Hanshin-Awaji (Kobe) earthquake killed more than 6500 on January 17, 1995. Many people barely escaped from the debris and actively saved buried people. Rescue facilities are really important for robust social systems. Robotics and mechatronics are effective for advanced rescue equipment and systems. However, there has been little research and development performed until now. In order for robotics researchers to start, analysis of the tasks and requirements is necessary. In this research, the processes of rescue activities just after the disaster were investigated. Specifications of rescue robotic facilities are proposed on the basis of the analysis.

Various bipedal robots have been developed. What has been lacking, however, are bipedal robots that can perform "non-stationary motion". "Non-stationary motion" means sitting down, standing up, moving limbs, and so on. We have constructed a legged robot that can perform these movements without using the ankle-torque. Though it is natural to use ankle-torque for non-stationary motions, the usable amount of torque is restricted. We have to consider this input constraint when we design a control scheme to use ankle-torque for non-stationary motions. Since it is difficult to design a control scheme to use ankle-torque for general non-stationary motion, we focus on standing upright (a special non-stationary motion). Concretely, we gave an invariant set where ankle-torque is effective, and designed a hybrid control scheme that alternates between nonlinear and LQ control schemes on the surface of the invariant set. We also discovered stability of the controlled system with constrained ankle-torque. Moreover, simulations demonstrated the effectiveness of the control scheme. We expect that it can also be applied to non-stationary motion in general.

When a natural disaster happens, it is very important to go to the scene to rescue people as soon as possible. However, it is very hard to transport materials for rescue activities because the disasters destroy roads all over the area. Therefore, we cannot use automobiles. Moreover, the landform of the area is so complex. We propose a kind of walking robot system named CUL: Carry and Power Assist Robot for Unspecified Landforms. To develop the system, we also propose a method for creating an environmental map. We call the method the Mold Tube method. We describe a prototype of CUL that has two cameras and two legs. We show a result of an experiment for a feasibility study.

The purpose of our research is to show the realization of nonstationary motions (sitting down and standing up motion, and manipulator motions, etc.) for a legged robot. We have previously (1994) proposed a design method for nonstationary motions, and we have shown that the resultant control system had a property of a kind of robustness against some modeling error theoretically. In this paper, we report that we developed an experimental apparatus named Sauro-Emu that is able to realize the sitting down and standing up motion with manipulator motions. Through some experiments, we show the effectiveness of our control scheme.

This paper shows the realization of sitting-down and standing-up motion of a legged robot. We present a new design method of nonlinear gain-scheduling-type control scheme for the sitting-down and standing-up motion of our legged robot called Emu. Then, through some experiments, we show the effectiveness of our control scheme.

A new design concept of a manipulator is proposed, which is called torque-unit manipulator (TUM). The TUM was just born out of an idea of utilizing counter-torque, and its position-controllability has been shown theoretically. Hence, mechanical implementation and experimental examination are very important for the TUM to be in practical use. In this paper, experimental results are shown using a prototype TUM which is 2 degree-of-freedom and a discussion is given.

In this report several propulsion systems of air cushion vehicles are introduced, and a state feedback control law for trajectory control of an air cushion vehicle is proposed. We consider that the vehicle should be controlled so that it may not drift sideways for good driving performance. We apply a Lyapunov-like function to develop a nonlinear state feedback control law. Effectiveness of the nonlinear state feedback control law for an ACV model is verified through numerical simulations.>

A necessary and sufficient condition has been shown for a set of base parameters to determine a inertial matrix to be positive definite for each configuration of a manipulator after continuous change of each joint variable of the manipulator is approximately considered as a finite set of discrete points. The condition enables us to judge if a set of estimated base-parameter values determines the inertial matrix to be always positive definite or not. A method also has been proposed to modify the estimated base-parameter values such that the set of them determines the inertial matrix to be always positive definite after it is judged not to do.>

The control ability of a human operator has several good points and is still needed in several fields. Therefore, to imitate the function of human operator, many theories have been developed, for example, fuzzy theory, neural network theory and so on. This paper tries to understand the control function of human operator from a viewpoint of many scientific fields such as cognitive science, biology and information science and tries to mimic it. Then the authors propose a framework of a cerebral model based intelligent control system (CEMICS)'.>

A base parameter set as a minimum set of inertial parameters whose values can determine a dynamic model uniquely is investigated for a general parallel and perpendicular manipulator with rotational joints only. The notion of a base parameter is useful for an efficient and accurate identification of the manipulator dynamic model. A set of inertial parameters described in linear combinations of link parameters directly and completely in closed form is given and proved to constitute a base parameter set. It can be derived from this that the minimum number of inertial parameters whose values can determine the dynamic model is 7N-4 beta /sub 1/ (7N-4 beta /sub 2/-2 if the first joint axis parallel to the gravity vector), where N is the number of links in the manipulator, and beta /sub 1/ is the number of links connected by joints whose axes are always parallel to the first joint axis. After defining the base parameter, it is also shown that any base parameter set can be obtained from one base parameter set by a nonsingular linear transformation. The method adopted has the potential advantage of determining the relations between base parameters and manipulator motions.>

The base parameters (nonredundant parameters that can generate the dynamic equations of motion) are investigated for general parallel and perpendicular manipulators with only rotational joints. A set of parameters that are simple combinations of the link is proved to be the base parameters by analyzing the dynamic equations and making clear the redundancies of the link parameters of the manipulators. The results can be applied to parameter identification of the manipulator dynamic models and in algorithms for solving the inverse dynamic problem.>