Motion mechanism and gait planning of a wheeled micro robot

Based on a novel shape memory alloy （SMA） actuator, a micro worming robot is presented. The robot adopts a wheeled moving mechanism. The principle of the robot＇s enlarged pace is introduced, and the structure and motion mechanism of the SMA actuator and the wheeled moving mechanism are discussed. The gait about the robot＇s rectilinear movement and turning movement is also planned. Under the effect of the eccentric wheel self-locking mechanisms and changing-direction mechanisms, the robot can move forward and backward, and turn actively, which overcomes the disadvantages of the traditional SMA micro robots to a certain extent. Furthermore, some experiments on the heating current of the SMA actuator and the robot＇s motion capability are carded out.

A Novel Bio-mimetic Wireless Micro Robot for Endoscope

A novel bio-mimetic wireless micro robot for endoscope is developed. Its autonomous manner is earthworm-like and driven by linear actuators based on DC motor. It is different from the conventional micro robot endoscope that wireless module is used for conanunicating and power transfer. The fabricated micro robot system is detailedly described, including structure, micro robot locomotion principle, communication control module and wireless power transfer module. The experimental results show that the driving force of the linear actuator can reach to 2. S5 N and supplying power is up to 480 mW DC power for receiving coil in the proposed system, which all fulfill the need of the micro robot system. The micro robot can creep reliably in the large intestine of pig and other contact environments.

A Pipeline Inspection Micro Robot Based on Screw Motion Wheels

The micro robot based on screw motion wheels, which features high payload/mass ratio, fast and continuous motion, adaptation to pipe diameter or roundness variations, is suitable for locomotion and inspection inside small diameter pipelines. The robot inspection system, Tubot I, developed at Shanghai University is composed of locomotion mechanism with an inner motor, a micro CCD camera and a monitor outside the pipeline. In the paper, the kinematics and statics analyses are presented for the screw locomotion system of Tubot I. The moving characteristics are obtained from experiments on the robot prototype.

Earthworm-like micro robot based on electromagnetic driver

According to the principle of bionics, a prototype of the earthworm-like micro robot was developed and manufactured for entering the small tube. Based on the process of the action and mechanics analysis, the controller was designed. This micro robot with 6mm diameter was driven directly by three electromagnetic linear drivers. Mobile cells were joined with two degree-of-freedom joint and the whole body was flexible and soft. The driving force reached 10.8g in normal working condition. The direction of movement and the angle of imaging can be controlled by the shape memory alloy （SMA）. The driving force, velocity and movement of micro robot in flexural tube were tested through experiments, which indicated that the driving force was in proportion to the range of frequency, and the micro robot could current, and the velocity reached a maximum in certain move in the thin tube flexibly.

Hardware Neural Networks Controlled MEMS Rotational Actuators and Application to Micro Robot

Hardware neural networks controlled rotational actuators and application to an insect type micro robot are reported in this paper. Millimeter size rotational actuators are fabricated by combining MEMS （Micro Electro Mechanical System） technology and shape memory alloy based artificial muscle wires. The actuator is composed of a pair of disk rotators and each rotor is suspended by four artificial muscle wires that are connected to the silicon frame. The rotational motion is generated by flowing the electrical current to each wire successively. Two actuators of different sizes are fabricated. The large actuator shows the displacement of 0.5 mm at the cycle time of 4 s. The small actuator shows 0.3 mm at 2 s. For controlling the actuator, the hardware neural networks are used. The hardware neural networks are composed of electrical circuits imitating cell bodies, excitatory synapses and inhibitory synapses. Four signal ports are extracted from four pairs of excitatory and inhibitory neurons and they are connected to the actuator. The small actuator is applied to the robot and built in the mid body of the robot. The shaft of the actuator is connected to the link mechanisms that transform the rotational motion to the locomotion. The appearance dimensions of the robot are 4.0, 2.7, 2.5 mm width, length and height. The robot performs forward and backward foot step like insects. The speed is 26.4 mm·min^-1 and the stepping width is 0.88 mm. Also, the robot changes the direction by external trigger pulses.

NEW KIND OF WIRELESS MICRO ROBOT ACTUATED AND CONTROLLED THROUGH OUTSIDE MAGNETIC FIELD

A new method to drive and control micro in-pipe robot by means of magneticfield outside pipe is put forward, in which wireless micro robot can move forward driven by thevibration of its legs through converting magnetic energy into mechanical one under the action ofpiezomagnetism and magnetomechanical coupling of its micro GMA, when time varied oscillatingmagnetic field with different frequency applied outside pipe. Firstly its systematical structure andoperation principle are introduced, and energy converting process from outside magnetic one intomechanical one is analyzed through setting up the magnetic and mechanical dynamic model of GMA andestablishing dynamic model of two stage amplifier of mobile earner. Robot systematical experimentsshow the correctness of the theoretical analysis and its feasibility. As a result, drive and controlmethod without cable through outside magnetic field is realized.

A Sub-100 mg Electromagnetically Driven Insect-inspired Flapping-wing Micro Robot Capable of Liftoff and Control Torques Modulation

Inspired by the unique,agile and efficient flapping flight of insects,we present a novel sub-100 mg,electromagnetically driven,tailless,flapping-wing micro robot.This robot utilizes two optimized electromagnetic actuators placed back to back to drive two wings separately,then kinematics of each wing can be independently controlled,which gives the robot the ability to generate all three control torques of pitch,roll and yaw for steering.To quantify the performance of the robot,a simplified aerodynamic model is used to estimate the generated lift and torques,and two customized test platforms for lift and torque measurement are built for this robot.The mean lift generated by the robot is measured to be proportional to the square of the input voltage amplitude.The three control torques are measured to be respectively proportional to three decoupled parameters of the control voltages,therefore the modulation of three control torques for the robot is independent,which is helpful for the further controlled flight.All these measured results fit well with the calculated results of the aerodynamic model.Furthermore,with a total weight of 96 mg and a wingspan of 3.5 cm,this robot can generate sufficient lift to take off.

ANALYZING ON THE VIBRATION CHARACTERISTICS OF A MICRO PIEZOELECTRIC ROBOT IN PIPELINE

The mathematical model of a micro piezoelectric elastic legged robot in pipeline was founded. The robotic resonant frequency worked out with the mathematical model is nearly equal to the frequency from experiment. It indicates that the mathematical model of the robot is correct. Besides, it studied the piezoelectric robotic structure parameters’ effect on the robotic performance. The result of the analysis on the robot constructs the base of an optimal design of a piezoelectric robot.

GIANT MAGNETOSTRICTIVE ACTUATOR IN SERVO VALVE AND MICRO PIPE ROBOT

Performance of giant magnetostrictive material (GMM) is introduced. Principleof work, basic structure and key techniques of giant magnetostrictive actuator (GMA) are analyzed.Its dynamic models of magneto-mechanical coupling are established. The structure and principle ofthe pneumatic servo valve and the micro pipe robot with new homemade GMM are presented. Theexperiment is carried out under typical working conditions. The experiment results show that the GMMpneumatic servo valve has wide pressure control characteristics, good linearity, and fast responsespeed. The movement principles of the GMM robot system are reliably feasible and its maximal movingspeed is about 8 mm/s. It is preferable to the driving frequency of the robot within 100 approx 300Hz.

Fast filtering algorithm based on vibration systems and neural information exchange and its application to micro motion robot

This paper develops a fast filtering algorithm based on vibration systems theory and neural information exchange approach. The characters, including the derivation process and parameter analysis, are discussed and the feasibility and the effectiveness are testified by the filtering performance compared with various filtering methods, such as the fast wavelet transform algorithm, the particle filtering method and our previously developed single degree of freedom vibration system filtering algorithm, according to simulation and practical approaches. Meanwhile, the comparisons indicate that a significant advantage of the proposed fast filtering algorithm is its extremely fast filtering speed with good filtering perfi^rmance. Further, the developed fast filtering algorithm is applied to the navigation and positioning system of the micro motion robot, which is a high real-time requirement for the signals preprocessing. Then, the preprocessing data is used to estimate the heading angle error and the attitude angle error of the micro motion robot. The estimation experiments illustrate the high practicality of the proposed fast filtering algorithm.

An in-pipe micro robot actuated by piezoelectric bimorphs

A novel in-pipe micro robot providing stable and accurate locomotion inside a tubular structure with diameters ranging from 16 mm to 18 mm is presented in this paper. Driven by impulsive voltages, deflections of the piezoelectric bimorphs are generated and then converted into translational locomotion by the principle of the Impact Drive Mechanism (IDM). Theoretical analysis of the proposed system is performed based on a simplified mechanical model. Then dynamic simulations of the dynamic behavior are performed. Finally, an experiment is conducted to investigate the moving ability of this device. The results demonstrate that a maximum translational velocity of 3.5 mm/s can be obtained under an impulsive driving voltage with peak value at 50 V and frequency of 1100 Hz. Both theoretical analysis and experimental trials prove that the principle of IDM actuated by piezoelectric bimorphs is feasible and robust for achieving accurate locomotion of the micro robot in pipes with diameters of less than 20 mm.

Modeling and Configuration Design of Electromagnetic Actuation Coil for a Magnetically Controlled Microrobot

Non-contact actuated microbeads have attracted a lot of attention in recent years because of its enormous potential in medical, biological, and industrial applications. Researchers have proposed a multitude of electromagnetic actuation(EMA) systems consisting of a variety of coil pairs. However, a unified method to design and optimize a coil pair according to technical specifications still does not exist. Initially, this paper presented the modeling of an untethered ferromagnetic particle actuated by externally applied magnetic field. Based on the models, a simple method of designing and optimizing the EMA coil pair according to technical specifications, was proposed. A loop-shaped coil pair generating uniform magnetic and gradient fields was chosen to demonstrate this method clearly and practically. The results of the optimization showed that the best distance to radius ratio of a loop-shaped coil pair is 1.02 for a uniform magnetic field and 1.75 for a uniform gradient field. The applicability of the method to other shapes of coil configuration was also illustrated. The best width to distance ratio for a square-shaped coil pair is 0.558 and 0.958 for uniform magnetic and gradient fields, respectively. The best height to width ratio and distance to width ratio for a rectangle-shaped coil pair is h/w =[0.9,1.1], d/w =[0.5,0.6] for uniform magnetic field and h/w =[1.0,1.2], d/w =[0.9,1.1] for uniform gradient field. Furthermore, simulations of a microparticle tracking the targeted trajectory were conducted to analyze the performance of the newly designed coils. The simulations suggested the ability of manipulating microparticles via the coils designed by our proposed method. The research mainly proposed a unified design and optimization method for a coil pair, which can support researchers while designing a specific coil pair according to the technical requirements. This study is aimed at researchers who are interested in EMA system and microrobots.

MICRO-ROBOT FOR MEASUREMENT AND THREE-DIMENSION RECONSTRUCTION OF MICROPIPES

The presented system consists of field devices, a control system and a host computer system. The field devices, which are composed of an in-pipe micro-robot, a displacement sensor, a curvature sensor, and an inner surface measurement unit, can go into the pipe to get the data of displace- ment and axis curvature, and the shape data of the inner surface. With the conic-shape laser beam shot by the inner surface measurement unit, the intersectional curve between the laser beam and the inner-surface of the tested pipe can be calculated in the local coordination system （LCS） of the inner surface measurement unit. The relation between the LCS and the global coordination system （GCS） can be deduced, too. After the robot reaches the end of the pipe, all measured intersectional curves can be translated into the same coordination system to become a point cloud of the inner surface of the pipe according to the relations between LCS and GCS. Depending on this points cloud, the CAD model of the inner surface of the pipe can be reconstructed easily with reverse engineering tools, and the feature of flaw of the pipe can be obtained with flaw analysis tools.

A Study on Anchoring Ability of Three-Leg Micro Intestinal Robot

This paper proposes an anchoring and extending micro intestinal robot for medical inspection and surgery propose. The three-leg anchoring method is discussed in detail, and micro robot phantom model is used to test anchoring related parameters for mechanical design. A prototype is designed and fabricated base on the experiment results and is tested in in-vitro experiment. The prototype is locomotive in a pig small intestine under a diameter limitation.

The Intellectualized Architecture of the Autonomous Micro- Mobile Robot Based- Behavior

Given the difficulty in hand coding task schemes, an intellectualized architecture of the autonomous micro mobile robot based behavior for fault repair was presented. Integrating the reinforcement learning and the group behavior evolution simulating the human's learning and evolution, the autonomous micro mobile robot will automatically generate the suited actions satisfied the environment. However, the designer only devises some basic behaviors, which decreases the workload of the designer and cognitive deficiency of the robot to the environment. The results of simulation have shown that the architecture endows micro robot with the ability of learning, adaptation and robustness, also with the ability of accomplishing the given task.

Mobile MicroRobotin Small Pipe Driven by ElectroMagnetic Force

It is required to develop micro machine for inspection and maintenance of defects inside small pipe with diameter smaller than one inch. Considering the advantages of electromagnetic actuators with simple mechanism, high response, convenience to control and fabricate, we tried to develop a new micro robot in small pipe based on interaction principle of electromagnetic attraction and spring force. This paper describes its structure and design. The dimension of the prototype is diameter of 15 mm, length of 30 mm and weight of 25 g. It can climb in small pipe of diameter of 20 mm with a speed of 6～8 mm/s in horizontal or in vertical situation.

A Novel Vision Localization Method of Automated Micro-Polishing Robot

Based on photogrammetry technology,a novel localization method of micro-polishing robot,which is restricted within certain working space,is presented in this paper.On the basis of pinhole camera model,a new mathematical model of vision localization of automated polishing robot is established.The vision localization is based on the distance-constraints of feature points.The method to solve the mathematical model is discussed.According to the characteristics of gray image,an adaptive method of automatic threshold selection based on connected components is presented.The center coordinate of the feature image point is resolved by bilinear interpolation gray square weighted algorithm.Finally,the mathematical model of testing system is verified by global localization test.The experimental results show that the vision localization system in working space has high precision.

Micro-Scale Motion Precision Simulation Method for a New-Type 6-DOF Micro-Manipulation Robot

A new 6-DOF micro-manipulation robot based on 3-PPTTRS parallel mechanisms in combination with flexure hinges is proposed. The design principle of the mechanism is introduced, and the kinematics analysis method based on differentiation is used to get the (inverse) kinematics equations. Then a micro-scale motion precision simulation method is proposed according to finite element analysis (FEA), and the prediction of robot’s motion precision in design phase is realized. The simulation result indicates that the 6-DOF micro-manipulation robot can meet the design specification.

Static Stiffness Analysis of a New Type 6-DOF Micro-manipulation Robot

A 6-DOF micro-manipulation robot based on a 3-PPTTRS mechanism is proposed in this paper.Its static stiffness is an important index to evaluate load capacity and positioning accuracy.However,it is insufficient to consider the static stiffness only when the robot is in its initial pose.The stiffness in different positions and poses in its work space must be analyzed also.Thus a method to analyze the relationship between static stiffness and poses in the whole work space is presented.A static stiffness model is proposed first,and the relationship between structural parameters and static stiffness in different poses is discussed.The static stiffness analysis provides foundation for structural parameter design.

磁性微型机器人的自动化操控研究综述

微型机器人是指尺度在毫米及其以下(几百纳米到几毫米)的一类机器人,是机器人研究领域的一个重要分支.低强度电磁场无线操控的微型机器人,可以在狭小的空间运动,完成复杂的作业任务,在微操作、靶向药物输送和体内传感标记等生物医学研究中有着广泛的应用前景.经历几十年的发展,研究人员在机器人的结构设计、微纳制作和伺服控制方面贡献了许多重要理论和实践成果.本文旨在介绍自动化方法在磁性微型机器人中的应用,主要包含运动建模、闭环控制和路径规划方面的研究内容,并讨论磁性软体微型机器人在建模与运动控制方面存在的挑战.最后,提出磁性微型机器人在控制与规划方面的研究方向.