Mantian Li

A Wireless Distributed Wall Climbing Robotic System for Reconnaissance Purpose

The paper proposes a wireless distributed wall climbing robotic system for reconnaissance purpose. Firstly, we introduce the mechanism of the distributed wall climbing robotic system. The mother wall-climbing robot of one single suction cup with two wheels locomotion system enables fast motion and can adapt nearly any kind of vertical wall surface in urban environment. The child wall climbing robot is an inchworm-like biped mechanical structure with the advantages of small size and minimal weight, which enables the robot translate from one surface to another and can avoid detection. Secondly, embedded controllers of wall climbing robotic system are designed. TMS320LF2000trade digital signal processor (DSP) from Texas Instrumentstrade was selected for multi-motor control and sensory confusion since it demonstrates high-speed performance. With the Li-battery energy supply and wireless communication system, robots have the ability to explore the world semi-autonomously. Lastly, experiments were taken to evaluate the efficiency of the distributed robotic system

A Novel Locomotion Principle for Endoscopic Robot

Endoscopes are medical devices which can diagnose various kinds of diseases throughout the whole gastrointestinal (GI) tract. The conventional endoscopes cannot reach the small intestines and generate pain and discomfort to patients due to the stiffness of their body. Such disadvantages do not exist in endoscopic robots. However, the soft and elastic characters make the locomotion efficiency of endoscopic robot very low. To resolve this problem, it is necessary to find a special locomotion principle which fit the GI tract. In this paper, a novel locomotion principle is proposed, which is the first time used in the endoscopic robot. The locomotion principle is obtained by analyzing, simulating and simplifying the movement of mucuscilia system. To evaluate its performance, a prototype of the endoscopic robot adopting this locomotion principle is developed, which is driven by shape memory alloy (SMA) actuator. An invitro experiment shows that the robot can move successfully with efficiency about 27%. The result of experiment validates that the proposed locomotion principle fit the GI tract well

A New Wavelet Based Multi-focus Image Fusion Scheme and Its Application on Optical Microscopy

Multi-focus image fusion is a process of combining two or more partially defocused images into a new image with all interested objects sharply imaged. In this paper, after reviewing the multi-focus image fusion techniques, a wavelet based fusion scheme with new image activity level measurement is presented. The proposed multi-resolution image fusion technique includes three steps: first, multi-resolution discrete wavelet transform (DWT) is applied to obtain the wavelet coefficients of the source images. Then, applying proposed coefficients fusion scheme to the obtained coefficients, the wavelet coefficients of the fusion image are reconstructed. Finally, the final fusion image is generated by applying inversed wavelet transform. In experiments, artificial defocused images (by applying low-pass filter to the specified regions) are utilized to investigate the performance of proposed scheme and to select suitable wavelet family and wavelet decomposition scales. Then we apply the proposed image fusion scheme to optical microscopy domain to solve the short depth of focus characteristic of optical microscope. The experiments results verify the validity of the proposed multi-focus image fusion scheme.

Design and Test of a Capsule Type Endoscope Robot with Novel Locomation Principle

Robots become more and more widely used in medical application especially in minimally invasive surgery (MIS) these years, and endoscope robot is a typical example. There is sill not a kind of conventional endoscope which can reach the whole gastrointestinal (GI) tract. And conventional endoscopes generate pain and discomfort to patients due to the stiffness of their body. Such disadvantages do not exist in endoscope robots. However, the soft and elastic characters of GI tract make the locomotion efficiency of endoscope robot very low. To resolve this problem, it is necessary to find a special locomotion principle which fit the GI tract, and many researchers have paid a lot of effort. In this paper, a novel locomotion principle is proposed, which is the first time used in the endoscope robot. The locomotion principle is obtained by analyzing, simulating and simplifying the movement of mucus-cilia system. To evaluate its performance, a prototype of the endoscope robot adopting this locomotion principle is developed, which is driven by shape memory alloy (SMA) actuator. An in-vitro experiment shows that the robot can move successfully with efficiency about 27%. The result of experiment validates that the proposed locomotion principle fit the GI tract. And some suggestions to enhance the locomotion efficiency are proposed

Global visual servoing of miniature mobile robot inside a micro-assembly station

This paper focuses on designing the 2D global visual servoing system of the miniature mobile robot. The global vision sensor supervises the robots workspace to detect the position and orientation of the robot, and then navigates the robots end-effector into view field of the microscope to accomplish MEMS (micro electric mechanical system) parts assembly. To meet requirements of real-time control and high precision tracking, three LEDs forming a non-isosceles-rightangled triangle are mounted on the top of the robot platform. Visual servoing is realized with dynamic look and move mode, and the controller is designed in the image space. With the global visual navigation, the robot can be controlled with accuracy about 0.5-1 mm. But due to the lack of interior sensor for the manipulator, when the macro motion is completed, the end-effector is not guaranteed inside view field of microscope. The strategy for end-effector searching, which based on motion inspection, is designed to solve the problem. Experiment shows that the end-effector can be located in the view of microscope successfully. It is the essential precondition for our robot accomplishing micro operation task.

Design and Passable Ability of Transitions Analysis of a Six Legged Wall-Climbing Robot

A new type of six legged wall-climbing robot with modular joints for the anti-terrorist field is proposed in this paper. It can move quickly and quietly with the help of passive joints on its ankle and the silent vacuum generators. Design of the vacuum producer is presented at first. Then the analyses of the torque on each joint and the structure design of them are presented in detail. Finally we analyze the passable ability of the transition using kinematics for enhancing the performance of the robot.

A New Auto-focusing Algorithm for Optical Microscope Based Automated System

Pixel-based auto-focusing is a long-standing topic in the literatures. It involves three main parameters: Region of Interest (ROI), image sharpness function and global maximum searching algorithm. As the mathematical description of image sharpness, sharpness function is the core issue for realizing robust auto-focusing. In this paper, the existing sharpness functions are summarized and grouped firstly, then a new space domain SUSAN (Smallest Univalue Segment Assimilating Nucleus) based sharpness function is proposed. The key problem in proposed algorithm is selecting a suitable similarity function to measure the similarities of the sampling pixel and its neighbors. In experiments, 8 similarity functions are analyzed and evaluated. Based on the evaluation results, a rough/fine two grades global maximum searching strategy is designed to realize fast and robust auto-focusing. At last, experiments verify the validity of the proposed auto-focusing algorithm.

Structure optimization of the endoscopic robot ciliary leg based on dimensional analysis

Endoscopic robot propelled by ciliary legs is a new type in the endoscopic family. Composed by the ciliary leg locomotion modules, the robot presented in this paper is propelled by the rhythmic motion of the ciliary legs. Since the robot works in the complex intestinal environment which is full of viscous liquids, the friction between ciliary legs and intestinal tract becomes crucial for the locomotion of the robot. We investigate the mechanism of the friction with dimensional analysis. Three main dimensionless variables have been extracted from various factors affecting the friction coefficient between ciliary legs and intestinal tract. The study also carried out optimization of those three dimensionless variables via orthogonal test. Those optimization values can lead to the greatest friction coefficient.

Design of a six legged wall-climbing robot

A new type of six legged wall-climbing robot with modular joints for the anti-terrorist field is proposed in this paper. It can move quickly and quietly with help of passive joints on its ankle and a silent vacuum generator. Design of the mobile system is first described. Then the analyses of the torque on each joint and the structure design of them, as well as the vacuum producer are presented in detail. Finally, the kinematics model of robot is also established.

The Research of A Parent-children type robot system

A parent-children type robot currently being built at Harbin Institute of Technology is proposed. The parent robot is a quadruped hybrid robot based on behaviour control architecture weighing 25 KG and load capacity of 30 KG. The robot could move by wheels equipped on the feet with the speed up to 0.7m/s. On rough terrain, the robot could walk with speed up to 0.2m/s. The robot could climb stair, and turn around its centre of mass. It could carry up to seven children robot in its abdomen. The children robot is some modular reconfigurable track micro-robots. The children robot is compact, small and light. Weight of one module is 350 g. They could run separately, and several modules could reconfigure to chain robot or loop robot. Five modules children chain robot could climbing standard stairs. Experiments testified the performance of the parent robot and the children robot.