Development of snake-like robot ACM-R8 with large and mono-tread wheel

One of the important advantages of an active wheeled snake-like robots is that it can access narrow spaces which are inaccessible to other types of robot (such as crawlers, walking robots), since snake-like robots have an elongated, narrow body. Additionally, in areas with rubble, snake-like robots can traverse rough terrain and large obstacles since its body can conform to the terrain’s contours. ‘ACM-R8’ is a new snake-like robot which can climb stairs and reach doorknobs in addition to the features explained above. To fulfill these functions, the design of this robot incorporates several key features: joints with parallel link mechanism, mono-tread wheels with internal structure, force sensors and ‘swing-grousers’ which were developed to improve step climbability. In this paper, the design and control methods are described. Experiments confirmed high mobility on stairs and steps, with the robot succeeding in overcoming a step height of 600 mm, despite the height of the robot being just 300 mm.     

Development of a single-wheeled inverted pendulum robot capable of climbing stairs

ABSTRACT

In this paper, we propose the design of a single-wheeled robot capable of climbing stairs. The robot is equipped with the proposed climbing mechanism, which enables it to climb stairs. The mechanism has an extremely simple structure, comprised of a parallel arm, belt, harmonic drive, and pulley. The proposed climbing mechanism has the advantage of not requiring an additional actuator because it can be driven by using a single actuator that drives the wheel. The robot is equipped with a control moment gyroscope to control the stability in a lateral direction. Experimental results demonstrate that the robot can climb stairs with a riser height of 12–13?cm and a tread depth of 39?cm at an approximate rate of 2 to 3 s for each step.     

Development of a stair-climbing mobile robot with legs and wheels

This paper deals with the development of a stair-climbing mobile robot with legs and wheels. The main technical issues in developing this type of robot are the stability and speed of the robot while climbing stairs. The robot has two wheels in the front of the body to support its weight when it moves on flat terrain, and it also has arms between the wheels to hook onto the tread of stairs. There are two pairs of legs in the rear of the body. Using not only the rorational torque of the arms and the wheels, but also the force of the legs, the robot goes up and down stairs. It measures the size of stairs when going up and down the first step, and therefore the measurement process does not cause this robot to lose any time. The computer which controls the motion of the robot needs no complicated calculations as other legged robots do. The mechanism of this robot and the control algorithm are described in this paper. This robot will be developed as a wheelchair with a stair climbing mechanism for disabled and elderly people in the near future. This work was presented, in part, at the International Symposium on Artificial Life and Robotics, Oita, Japan, February 18–20, 1996     

Study on mobile mechanism of a climbing robot for stair cleaning: a translational locomotion mechanism and turning motion

In human living environments, it is often the case that the cleaning area is three-dimensional space such as a high-rise building. An autonomous cleaning robot is proposed so as to move on all floors including stairs in a building. When a robot cleans in three-dimensional space, it needs to turn for direction in addition to climb down stairs. The proposed robot selects movement using legs or wheels depending on stairs or flat surfaces. In this paper, a mobile mechanism and a control method are described for translational locomotion. The translational mechanism is based on using two-wheel-drive type omni-directional mobile mechanism. To recognize a stair using the position-sensitive detector, the robot shifts from translational locomotion to climbing down motion or edge-following motion. It is shown that the proposed robot turns to face a stair with the accuracy of 5°.     

基于姿态角的轮腿机器人驱动控制系统研究

在城市楼道环境中,尤其在面对楼梯等障碍时,五星形轮腿式机器人具有越障能力强、控制简单的优势。为防止机器人在攀爬楼梯时出现较大偏航倾斜,通过仿真软件ADAMS和Simulink中建立了五星形轮腿式机器人的整车动力学模型和PID速度控制模型。结果表明,该联合仿真控制模型能有效、快速地控制机器人速度,减小偏航角度,降低了研究和开发成本。将该驱动控制系统移植到原机器人系统中,并分析了机器人在本控制系统控制下攀爬楼梯等特殊情况下的稳定性能。     

基于传感器信息融合的移动机器人自主爬楼梯技术研究

机器人自主爬楼梯是移动机器人完成危险环境探查、侦察、救灾等任务需要具备的基本智能行为之一.分析了楼梯的多样性和履带式机器人爬楼梯固有的不稳定性导致机器人爬楼梯工作的复杂性,描述了带前导手臂的履带式移动机器人爬楼梯的步骤,简要介绍了利用超声波、视频摄像头和激光扫描测距仪信息来感知楼梯和判断机器人与楼梯相对位置的算法,最后提出了一个基于传感器测量值可信度的信息融合方法进行楼梯参数感知和行驶方向计算的机器人自主爬楼梯的控制系统结构.     

Optimal design of a stair-climbing mobile robot with flip mechanism

Stairs overcoming is a primary challenge for mobile robots moving in human environments, and the contradiction between the portability and the adaptability of stair climbing robot is not well resolved. In this paper, we present an optimal design of a flip-type mobile robot in order to improve the adaptability as well as stability while climbing stairs. The kinematic constraints on the flip mechanism are derived to prevent undesired interferences among stairs, wheels and main body during climbing stairs. The objective function is proposed according to the traction demand of the robot during stair-climbing motion for the first time and the value of the objective function is calculated though kinetic analysis. The Taguchi method is using as the optimization tool because of its simplicity and cost-effectiveness both in formulating an objective function and in satisfying multiple constraints simultaneously. The performance of the robot under the optimal parameters is verified through simulations and experiments.     

Development and field test of the articulated mobile robot T2 Snake-4 for plant disaster prevention

Abstract

In this work, we develop an articulated mobile robot that can move in narrow spaces, climb stairs, gather information, and operate valves for plant disaster prevention. The robot can adopt a tall position using a folding arm and gather information using sensors mounted on the arm. In addition, this paper presents a stair climbing method using a single backward wave. This method enables the robot to climb stairs that have a short tread. The developed robot system is tested in a field test at the World Robot Summit 2018, and the lessons learned in the field test are discussed.     

一种有效爬越楼梯的模块化可重组履带结构

针对楼宇内的移动监视和非结构化环境 ,研究了一种可重组的“履带—关节”机器人结构 ,通过模块化组合 ,它以很小的体积 (每个模块长 30cm ,宽 11.5cm ,高 11cm) ,获得了爬越楼梯的能力 .本文分析了履带机构爬越楼梯的原理 ,并实验论证了各种组合结构的地形适应性和移动能力 .     

六轮移动机器人爬楼梯能力分析

研究了PBJ-01防暴机器人攀越楼梯的能力. 从机器人对楼梯的几何包容、机器人重心和机器人爬楼梯过程中的最大俯仰角对机器人倾覆的影响等多方面考虑, 得出机器人能够爬越楼梯时楼梯参数必须满足的条件. 在该机器人的行为决策中, 为其选择越障还是避障提供了依据.     

Development of a folding arm on an articulated mobile robot for plant disaster prevention

Abstract

In this work, we develop a folding arm on an articulated mobile robot to inspect an industrial plant. The design targets of the arm, its operations, measurement ability, and mobility, were set for the task of inspecting an industrial plant. To accomplish the targets, we designed the folding arm considering both accessibility to high locations and the mobility of the articulated mobile robot to which it is attached. The arm has links, joints, dummy wheels, and sensors and enables the robot to which it is attached to manipulate objects, e.g. rotating valves, opening a door, or inspecting by accessing high locations. In addition, changing the posture of the arm and touching the dummy wheel in the arm to the surrounding terrain can reduce any negative effect of the arm on the robot's mobility when it encounters narrow spaces, stairs, steps, and trenches. The arm is controlled as a six degrees-of-freedom manipulator without redundancy by an operator who directly sets two joint angles. The effectiveness of the developed arm was demonstrated not only through experiments in a laboratory but also in a field test at the Plant Disaster Prevention Challenge of the World Robot Summit 2018.     

Ascending and descending stairs for a biped robot

This paper synthesizes an efficient walking pattern for a practical biped robot when ascending and descending stairs. The main features of the biped robot include variable length legs and a translatable balance weight in the body. The biped robot's walk is a mixture of both statically stable and dynamically stable modes and relies on some degrees of static stability provided by large feet and by carefully controlling the center of gravity's position. The paper describes the design and experiment of a 7-DOF practical biped which is capable of ascending and descending stairs, and the synthesis of an efficient walking gait for ascending and descending stairs. Our biped robot is one of the few biped walking machines capable of ascending and descending stairs     

Dynamic modeling and step-climbing analysis of a two-wheeled stair-climbing inverted pendulum robot

ABSTRACT

In this study, the control of a two-wheeled stair-climbing inverted pendulum robot and its climbing motion are analyzed and discussed. The robot adopts a state-feedback controller with a feed-forward constant to stabilize the body and achieve step-climbing motion. The control parameter is considered based on the dynamic model motion on a flat surface and the static model of motion on the step. For climbing stairs with a narrow step tread, a constant torque is applied to reduce the space required for recovering the body stability after climbing. The stability of the robot is numerically analyzed by analyzing the orbital stability of its limit cycle. The stability analysis shows that the control method can achieve a stable stair-climbing motion. The effectiveness of the control method is demonstrated through an experiment. The result indicates that the robot can climb the stairs, and the required time for climbing a single step is approximately 1.8?s.     

主从履带复合式机器人越障研究

针对机器人越障过程中的重心位置变化情况,提出一种主从履带复合式机器人越障研究方法。给出机器人样机模型,研究样机的重心变化规律和主履带系统链轮的负载扭矩变化规律,并进行越障和楼梯仿真分析。仿真结果表明,重心变化是影响越障和爬越楼梯成功与否的关键因素,样机重心位置发生变化时,履带系统链轮转矩将出现最大值。     

含有非驱动关节机器人的学习控制

含有非驱动关节的机器人的运动控制比一般的机器人要困难得多．因为非驱动关节 不能直接控制，系统属于非完全可控系统，一般的光滑反馈控制方法对这样的系统是无效的 ．本文提出了一种学习控制的方法，通过学习获得高精度的前馈控制，实现欠驱动机器人的 高精度运动控制，并在一台实际的欠驱动机器人上进行了实验，给出了实验结果．     

模块化可重构履带式微小型机器人的研究

研制了一种模块化可重构履带式微小型机器人．单个微小型机器人可以独立运行,多个微小型机器人可以重构成链形机器人和环形机器人．微小型机器人结构紧凑、体积小、重量轻．采用了微控制器和PC机两级控制体系,两级间采用蓝牙通讯．实验结果验证链形机器人具有较强的越障能力,能爬越楼梯;环形机器人具有高速及路面适应能力强的特点．     

Development of flexible joints for a humanoid robot that walks on an oscillating plane

In this study, we develop flexible joints for a humanoid robot that walks on an oscillating plane and discuss their effectiveness in compensating disturbances. Conventional robots have a rigid frame and are composed of rigid joints driven by geared motors. Therefore, disturbances, which may be caused by external forces from other robots, obstacles, vibration and oscillation of the surface upon which the robot is walking, and so on, are transmitted directly to the robot body, causing the robot to fall. To address this problem, we focus on a flexible mechanism. We develop flexible joints and incorporate them in the waist of a humanoid robot; the experimental task of the robot is to walk on a horizontally oscillating plane until it reaches the desired position. The robot with the proposed flexible joints, reached the goal position despite the fact that the controller was the same as that used for a conventional robot walking on a static plane. From these results, we conclude that our proposed mechanism is effective for humanoid robots that walk on an oscillating plane.     

Mobile robot with transformable crawler and intelligent guidance

Recently, great advances have been made in intelligent mobile robot technology, advances which will provide autonomous travelling ability to robots, allowing them to surmount stairs and other obstacles. In this paper, we present an active adaptive crawler mechanism and a visual navigating system, developed to achieve practical speed for industrial use of the mobile robot. By using a crawler-type mechanism, the active adaptive suspension mechanism maintains vehicle stability and achieves good climbing capability without increasing weight. Further, we have developed technology for an intelligent navigating mechanism, to guide the robot as it passes through a building. Once the robot is provided with an inner layout plan of the respective building, it can achieve practical mobile speed for industrial use.     

Global positioning of robot manipulators with mixed revolute and prismatic joints

The existing controllers for robot manipulators with uncertain gravitational force can globally stabilize only robot manipulators with revolute joints. The main obstacles to the global stabilization of robot manipulators with mixed revolute and prismatic joints are unboundedness of the inertia matrix and the Jacobian of the gravity vector. In this note, a class of globally stable controllers for robot manipulators with mixed revolute and prismatic joints is proposed. The global asymptotic stabilization is achieved by adding a nonlinear proportional and derivative term to the linear proportional-integral-derivative (PID) controller. By using Lyapunov's direct method, the explicit conditions on the controller parameters to ensure global asymptotic stability are obtained.     

Motion teaching method for complex robot links using motor current

Conventional robot motion teaching methods use a teaching pendant or a motion capture device and are not the most convenient or intuitive ways to teach a robot sophisticated and fluid movements such as martial arts motions. Ideally, a robot could be set up as if it were a clothing mannequin that has light limbs and flexible yet frictional joints which can be positioned at desirable shape and hold all the positions. To do the same with a robot, an operator could pull or push the links with minor forces until the desired robot posture is attained. For this, a robot should measure the applied external force by using torque sensors at the robot joints. However, torque sensors are bulky and expensive to install in every DOF joints while keeping a compact design, which is essential to humanoid robots. In this paper, we use only motor current readings to acquire joint torques. The equations used to compensate for the effect of gravity on the joint torques and the self-calibration method to earn link parameters are presented. Additionally, kinematic restrictions can be imposed on the robot’s arms to simplify the motion teaching. Here, we teach the Kendo training robot with this method and the robot’s learnt martial art motions are demonstrated.