1A2-A05 モジュール型ロボットの構成による機能拡張に関する研究 : 増解結機構の設計(複数ロボットの協調制御)

Self-reconfigurable robot is a kind of robot that is able to recover its original function after partial damage of the robotic system. This is achieved by making changes on the partially damaged robot. This paper put forward a kind of self-reconfigurable quadruped robot based on the resilient theory. First, the concept of the self-reconfigurable robot and the recovery strategy were introduced. Secondly, a novel architecture of modular quadruped robot made by LEGO material was proposed. The connector of interfaces was taken into consideration. At last, the overall mode of the motion and control method with the help of NXT G program were proposed. The analysis of the overall gait ensures the stability of motion in this phase. As for the uncertain environmental damage to the robot, the robot is able to repair itself by changing the movement type automatically to ensure it continues to work. The result shows that the quadruped robot meets the requirements of resilience and self-reconfiguration.

In this paper, in order to meet the requirements of stable foot support and balanced walking of quadruped hydraulic robot, a new control method is proposed. The "hard" contact between the feet of the quadruped hydraulic robot and the ground are changed into "semi flexible" contact to reduce the impact force produced by the contact and collision of the two and reduce the unbalance of the force. The designed "semi flexible" scheme was to coat the "semi flexible" modified polytetrafluoroethylene (PTFE) material on the surface of the bottom material of the robot's foot. The modification of PTFE was optimized by SRIM, and the optimization scheme was selected for experimental study to obtain the Al2O3/PTFE material for which the abrasive resistance met the requirement of robot motion. It was also used in robot force imbalance control experiment research optimization. The study clearly revealed that it can effectively reduce the power of the impact force caused by the contact and collision of the feet of the quadruped robot and the ground, reduce the swing and the unbalance of the motion force of the quadruped robot, and meet the requirements of the precise positioning and the force balance walking of the motion of quadruped hydraulic robot to a certain extent.

For an easier and natural teleoperation of the quadruped walking robots, a user interface is developed with a steering wheel and an assembly of pedals. In order to change the speed and the direction of the quadruped walking robots according to the operation of the steering wheel and the pedal, an online gait transition method is developed. Using this human-machine interface and online gait transition, the operator can control the quadruped walking robots almost in the same way as a driver drives a car. A quadruped walking robot named JROB-2 is used in the experiments. As the steering wheel is also equipped with various control buttons, it is possible to assign various single command tasks, like stand up and sit down etc., to these buttons and hence control the robot for these tasks without even touching the keyboard or mouse. The paper presents the details of this interface.

Reduction of the energy consumption is one of the most important problems to utilize quadruped walking robots for various works on rugged terrain. The authors have studied basic strategy to achieve high energy efficiency when the quadruped walking robot do the motion essentially requires positive power by the analysis of body rising motion. This paper discusses the energy efficiency of the slope walking motion by the quadruped walking robot. First, we investigate the walking posture in consideration of ideal actuator characteristics where the robot consumes few negative powers at each joint which causes the main energy loss of the walking robot. Then, we investigate optimal walking posture in consideration of DC motor characteristics by the full search of three gait parameters which define the crawl gait. Furthermore, we derive the optimal walking motion by the optimization of three gait parameters which are kept constant during one cycle gait and instantaneous parameters such as body velocity and supporting forces changed at each moment simultaneously.

This paper proposes a quadruped walking robot that has high performance as a working machine. This robot is needed for various tasks controlled by tele-operation, especially for humanitarian mine detection and removal. Since there are numerous personnel landmines that are still in place from many wars, it is desirable to provide a safe and inexpensive tool that civilians can use to remove those mines. The authors have been working on the concept of the humanitarian demining robot systems for 4 years and have performed basic experiments with the first prototype VK-I using the modified quadruped walking robot, TITAN-VIII. After those experiments, it was possible to refine some concepts and now the new robot has a tool (end-effector) changing system on its back, so that by utilizing the legs as manipulation arms and connecting various tools to the foot, it can perform mine detection and removal tasks. Toaccomplish these tasks, we developed various end-effectors that can be attached to the working leg. In this paper we will discuss the mechanical design of the new walking robot called TITAN-IX to be applied to the new system VK-II.

In this thesis we present the design and implementation of a novel self-reconfiguring modular (SR-MR) robotic system: Roombots. We are aiming at three main applications with Roombots; locomotion through self-reconfiguration in the regular cubic 3D-lattice on structured surfaces, locomotion in non-structured environments applying central pattern generators (CPG) as the locomotion controller, and self-assembly and reconfiguration of static objects of the day-to-day environment, such as furniture. Robot assemblies from self-reconfigurable modular robots have the ability to adapt to a given task and working environment by altering their shape through a series of reconfiguration moves, and attachments and detachments between the modules. We are interested in self-reconfiguring modular robots for their shape-changing capabilities, and their distributed characteristics. We envision the following applications for Roombots: First, self-reconfiguration in a structured 3D lattice, i.e. a floor and walls equipped with connectors. Embedded connectors can provide pivot points for locomotion of SR-MR assemblies, and docking and recharging places for our adaptive furniture pieces. Second, our proposed concept for locomotion control of modular robots on non-structured ground are central pattern generators. Third, we would like to build adaptive and versatile furniture from modular robots and light-weight elements. In the following we are able to count more than 60 modular robotic systems, developed over the last two decades. However we were unable to identify an existing system which could provide us with all desired kinematic and geometric capabilities. This led us to design and implement a novel self-reconfiguring modular robotic system: Roombots. To tackle the module design we attempt to identify both meaningful design parameters from existing modular robots, and essential features for our applications. The combination of both leads to the kinematic and geometric description of the Roombots modules, and eventually to its implementation. In order to be able to assemble furniture from our Roombots units in the future, we need a reconfiguration framework which supports the specific requirements of Roombots. Metamodules made of two units attached in-series are attracted and guided by a virtual force-field, they use broadcast signals, look-up tables of collision clouds and simple assumptions about their near environment to reach their seeding positions, which are currently hand coded. For the task of locomotion in non-structured environments we propose a framework for learning to move with modular robots using central pattern generators and online optimization. The distributed implementation of CPGs offers an ideal substrate for producing locomotion patterns and for online learning, and an optimization framework for fast learning.

This article discusses the advantages of a modular robot that can reassemble itself for different tasks. Modular robots are composed of multiple, linked modules. Although individual modules can move on their own, the greatest advantage of modular systems is their structural reconfigurability. Modules can be combined and assembled to form configurations for specific tasks and then reassembled to suit other tasks. Modular robotic systems are also very well suited for dynamic and unpredictable application areas such as search and rescue operations. Modular robots can be reconfigured to suit various situations. Quite a number of modular robotic system prototypes have been developed and studied in the past, each containing unique geometries and capabilities. In some systems, a module only has one degree of freedom. In order to exhibit practical functionality, multiple interconnected modules are required. Other modular robotic systems use more complicated modules with two or three degrees of freedom. However, in most of these systems, a single module is incapable of certain fundamental locomotive behaviors, such as turning.

We have proposed the sway compensation trajectory of robot body to realize dynamically stable walking for a quadruped walking robot. This method uses the lateral motion of the robot body to keep a zero momentum point (ZMP) on a diagonal line between the support legs. However, energy consumption of the sway compensation trajectory is larger than the case without trajectory control because periodical acceleration of the body has to be generated to realize sway motion. In this paper, we propose a new sway compensation trajectory for a quadruped walking robot named 3D sway compensation trajectory. This method is the extension of conventional sway compensation trajectory toward three dimensional motion, and the position of ZMP is controlled not only by lateral body motion but also by longitudinal and vertical body motion. Next, we demonstrate that energy consumption for walking can be reduced by combining these motions through theoretical analysis and computer simulation, and an optimum 3D sway compensation trajectory that minimizes energy consumption is proposed. Optimum trajectory is applied to a quadruped walking robot and the validity of the proposed trajectory is verified using the dynamic motion simulator, ADAMS.

A new method, inspired by the gait of horses, for regulating the ground reaction force of a quadruped walking robot, is proposed. The method uses the mechanical stiffness switch with a dual‐spring structure inspired by an equine distal forelimb. This includes the use of a low‐stiffness spring activated at the moment of touchdown and a high‐stiffness spring for the support phase. This method has been applied to Jinpoong, a hydraulic quadruped walking robot, and has contributed to the robot's stable gait on uneven terrain.

Biological observations on tetrapods locomotion deduce that anti-phase synchronization (APS) between fore and rear parts is beneficial for achieving a high-speed walking. On the other hand, theoretical analysis and experimental studies on quadruped robots suggest that a flexible spine potentially improves the gait efficiency and adaptability via smoothing the ground collisions. However, these two mechanisms have never been placed together by a comprehensive investigation in terms of their synergetic effect. Namely, an advanced principle is still lacking in combining the APS and the spine flexibility for quadruped walking robots. To address this issue, we construct a mathematical model for a quadruped dynamic walker under different spine conditions. First, the APS effect is generated via entrainment-based control method under a rigid spine condition. Then, flexible spines realized by three kinds of springs are compared with the rigid one via theoretical analysis. The results suggest that the APS mechanism and the flexible spine can be synergized via an appropriate deformation control. The theoretical findings not only uncover locomotion control mechanisms for quadruped walking robots, but also provide additional understandings of tetrapods dynamic walking from a mechanical engineering point of view.

Modular robot is an approach to build the robot for various complex tasks with the promise of great versatility, robustness and lower cost. It can be used extensively to meet the demands of different tasks or different working environments by changing its shapes. Therefore, they can travel over or through obstacles, and go though small pipe. Even they can walk somewhat like a person on crutches. It is a key technology that how modular robot with vision to capture exact image information, as well as to extract the feature parameters of components real-timely, to recognize the component types, and to judge the position and posture of component. The quantity of the motion pattern will decide the adjustable ability of modular robot. So, dynamic vision control system is very important for modular robot, which can improve its moving ability and intelligent degree. With the help of the dynamic vision control system, the robot can accomplish different tasks in different working environments by itself, such as deciding routes and avoiding obstacles. In this paper, in order to improve the vision of modular robot, a kind of dynamic vision control system is analyzed and researched roundly, and two kinds of motion patterns for the modular robot are put forward.

This paper describes a quadruped walking robot with hydraulic driving. The model of the quadruped robot is built by ADAMS and the link coordinate system of the quadruped robot's leg is established based on the D-H parameter method with kinematics equations established. A hydraulic control system model is established by the theoretical analysis of the hydraulic system, and the stable walking of quadruped robot is simulated by using the joint simulation of MATLAB and ADAMS.

A modular robot has a distributed mechanical composition which can make various configurations and also make locomotion in a wide variety of configurations. Modular robots are thought to be useful in extreme or unknown environments by adaptively changing their shape and locomotion patterns. As for locomotion, two types can be used; one is whole-body fixed-configuration locomotion and the other is locomotion by self-reconfiguration. In this paper we deal with the former type of locomotion which is realized by coordinated joint actuation. So far, proposed control methods for whole-body locomotion by modular robots have been based on predefined locomotion sequences. However, locomotion based on predefined sequences cannot adapt to changing terrain conditions such as uphill, downhill, slippery and sticky grounds. To solve such problems, we propose a distributed control mechanism using a CPG controller which enables adaptive locomotion by modular robots. Besides the real-time CPG control we introduce a decentralized control mechanism for detecting the situation that the robot is stuck and initiating transformation to another shape for recovering the situation. The results of various hardware experiments by 4-legged structure prove the feasibility of the method for adaptive locomotion and transformation by our M-TRAN II modules.

The last few years have witnessed an increasing interest in modular reconfigurable robotics for education, inspired robotic research, and space applications. This paper presents the latest results of the Cube-M modular project. Firstly, an overview of the research achievements in modular robot is given. Then the new modular robot Cube-M with one degree of freedom, an improved version of the Y1 modular robot, is presented. After that, the discussion focuses on the realization of a distributed hardware and control. Each module has embedded intelligent capabilities with an independent onboard controller to enable the realization of completely modular design. In the end, a snake-like robot prototype is built to confirm the feasibility of our design principle.

Existing self-reconfigurable robots achieve connections and disconnections by a separate drive of the docking system. In this paper, we present a new docking system with which the connections and disconnections are driven by locomotion actuators, without the need for a separate drive, which reduces the weight and the complexity of the modules. This self-reconfigurable robot consists of two types of fundamental modules, i.e., active and passive modules. By the docking system, two types of connections are formed with the fundamental modules, and the docking and undocking actions are achieved through simple control with less sensory feedback. This paper describes the design of the robotic modules, the docking system, the docking process, and the docking force analysis. An experiment is performed to demonstrate the self-reconfigurable robot with the docking system.