MODELING METHOD FOR PRODUCT STRUCTURE MAPPING BASED ON REVERSE SOLVING OF LOCUS AND MOTION

Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality.     

Robust motion/force control of nonholonomic mobile manipulators using hybrid joints

In this paper, robust force/motion control strategies are presented for mobile manipulators under both holonomic and non-holonomic constraints in the presence of uncertainties and disturbances. The proposed control strategies guarantee that the system motion converges to the desired manifold with prescribed performance and constraint force control is developed using the passivity of hybrid joints rather than force feedback control. Experiment results validate that not only the states of the system asymptotically converge to the desired trajectory, but also the constraint force asymptotically converges to the desired force.     

Translating Structured English to Robot Controllers

Recently, Linear Temporal Logic (LTL) has been successfully applied to high-level task and motion planning problems for mobile robots. One of the main attributes of LTL is its close relationship with fragments of natural language. In this paper, we take the first steps toward building a natural language interface for LTL planning methods with mobile robots as the application domain. For this purpose, we built a structured English language which maps directly to a fragment of LTL.     

Formulation and motion planning of the peg-in-hole task with mixed logical dynamical system theory

It is well known that most assembly skills can be regarded as one of the signal-symbol hybrid dynamical systems, since the interactive dynamics between the end-effector and the environment change according to contact configurations (geometrical constraints). In this paper, we first propose a model of the peg-in-hole task, which is known as a typical assembly task. Mixed logical dynamical system theory is adopted to formulate the peg-in-hole task, and an optimal solution with both continuous and logical variables under an objective function is found systematically. Then, a strategy to find the optimal solution with less computation is proposed. Finally, some planning results for the peg-in-hole task are shown in order to verify the usefulness of the proposed method.     

On the Crystal Habit and Particle Size Distribution of AgBr Emulsions Prepared in the Presence of Synthetic Colloids

An account is given of the further experiments concerning the particle size distribution and crystal habit of AgBr particles in emulsions prepared in the presence of synthetic colloids such as polyacrylamide. paly-N-methylacrylamide and polr-N,N-dimethylacrylamide. The data have been obtained by examination of the emulsion with on electron microscope.     

Whole Body Motion Noise Cancellation of a Robot for Improved Automatic Speech Recognition

The motors of a robot produce ego-motion noise that degrades the quality of recorded sounds. This paper describes an architecture that enhances the capability of a robot to perform automatic speech recognition (ASR) even as the entire body of the robot moves. The architecture consists of three blocks: (i) a multichannel noise reduction block, consisting of microphone-array-based sound localization, geometric source separation and post-filtering, (ii) a single-channel template subtraction block and (iii) an ASR block. As the first step of our analysis strategy, we divided the whole-body motion noise problem into three subdomains of arm, leg and head motion noise, according to their intensity levels and spatial location. Subsequently, by following a synthesis-by-analysis approach, we determined the best method for suppressing each type of ego-motion noise. Finally, we proposed to utilize a control module in our ASR framework; this module was designed to make decisions based on instantaneously detected motions, allowing it to switch to the most appropriate method for the current type of noise. This proposed system resulted in improvements of up to 50 points in word correct rates compared with results obtained by single microphone recognition of arm, leg and head motions.     

微细作业系统工作台的微电机驱动控制

介绍了OEM6200步进电机控制器编程语言MOTION ARCHIECT的特点，以及如何应用其实现对由2台微电机驱动的作业台的控制。简述了MOTION ARCHITECT在对外通讯方面的一些特点，并提出了用VB6对其进行2次软件开发的一个实例。根据实际测试，该开发的界面具有宜人性好、可以满足操作过程对作业台精度和时间响应的要求等优点。     

Design of a vision-guided microrobotic colonoscopy system

In this paper presents a novel design of a microrobotic colonoscopy (MRC) system. The proposed microrobotic colonoscope is an autonomous vision-guided device, which is designed to navigate inside a human colon for the purpose of observation, analysis and diagnosis. It is developed to alleviate the shortcomings in the existing manual colonoscopy procedure, which is generally cumbersome and tedious for the colonoscopist and painful to the patients. The MRC system is divided into three areas, i.e. design of the microrobotic device, path planning and guidance, and offboard control system. A novel design of the microrobot is presented which utilizes a pneumatic mechanism to achieve locomotion and steering. A new concept of clamping the colon wall based on passive vacuum devices is suggested. General mathematical analysis governing the differential steering of the robotic tip is also described. The path planning of the microrobot is carried out based on the sensory fusion utilizing the quantitative parameters derived from the captured images and the tactile sensors. An off-board control system to control the directional movements of the microrobot is explained. The proposed colonoscopy system was tested with physical models and animal colons, and the experimental observations are presented.     

Visual control of two aerial micro-robots by insect-based autopilots

In the framework of our research on biologically inspired microrobotics, we have developed two novel Automatic Flight Control Systems (AFCs): OCTAVE ( Optical flow Control sysTem for Aerospace VEhicles) and OSCAR ( Optical Scanning sensor for the Control of Autonomous Robots), both based on insects' visuomotor control systems. OCTAVE confers upon a tethered aerial robot (the OCTAVE robot) the ability to perform terrain following. OSCAR gives a tethered aerial robot (the OSCAR robot) the ability to fixate and track a contrasting target with a high level of accuracy. Both OCTAVE and OSCAR robots are based on optical velocity sensors, the principle of which is based on the results of previous electrophysiological studies on the fly's Elementary Motion Detectors (EMDs) performed at our laboratory. Both processing systems described are light enough to be mounted on-board Micro-Air Vehicles (MAVs) with an avionic payload small enough to be expressed in grams rather than kilograms.     

Spherical Nanoparticle–Substrate Adhesion Interaction Simulations Utilizing Molecular Dynamics

From a molecular perspective, the fundamental rolling and sliding elasto-adhesion interactions between a spherical nano-particle and an elastic substrate is studied using a computational technique based on the Molecular Dynamics (MD) approach. Initially, the particle and the substrate were equilibrated individually at 300 K. The covalent bonds interactions between the atoms of the nanoparticle are modeled by constraining the atoms to stay together throughout the simulation. The temperature of the substrate atoms is regulated by periodically scaling to mimic the bulk substrate effect to minimize the effects of the finite substrate size. The intermolecular interaction between the particle and the substrate is defined by the Lennard–Jones (LJ) 12-6 potential. The total force–displacement curves of the 4.2 and 7.89 nm particles in the cases of particle being pushed normally towards the substrate and the particle pushed tangentially, while in adhesion with substrate, are obtained. The rolling resistance moment exhibited by the smaller nanoparticle (4.2 nm) is calculated from the force–displacement curve obtained from simulations and compared to the theoretical predictions based on a two-dimensional adhesion model. It is found that the moments as a function of the rotation angle are of the same order (3.64 nN nm). The rolling and sliding force–displacement profiles when the nanoparticle is subjected to tangential load are also presented.