Advanced Materials Research Vols. 308-310

Abstract: The paper presents a matrix representation of mechanical chains based on proposed joint-axis matrix, and a matrix operation of joints orientation change metamorphic processes. A four elements joint-axis matrix with joints types and orientations is developed first, and an augmented adjacency matrix of kinematic chains is formed by adding the elements of joint-axis matrix into the corresponding positions of general adjacency matrix of kinematic chains. Then the matrix operation of metamorphic process is performed through changing the orientation of metamorphic joint of augmented planar mechanism to transform the configuration of the mechanism from planar to spatial one.

Abstract: Owing to the deficiency of pinhole imaging model, a method to measure the depth information of the object based on lens imaging principle is proposed in this paper. By drawing on the two states of the measured object before and after changing position, this method manages to adjust the position of lens until the image become clearest, record the related information of position variation in order to obtain the depth information of the object. Meanwhile, whether the lens central plane is parallel to the CCD plane or not is also discussed, which is the reason why the image is fuzzy. A new kind of two degrees of freedom parallel adjusting mechanism was designed to solve the two problems above, which can achieve two degrees of freedom including independent moving and independent rotating. The clearest image can be obtained by adjusting the object distance and the image distance without changing the focal length of the camera. Besides, the mechanism can also be used to detect whether the installation position of lens central plane matches the CCD plane or not.

Abstract: This paper present formation principle of any spherical trajectory curve, and kinematic track of spherical 2-DOF parallel manipulator with actuation redundancy was planned by trajectory planning method that acceleration is continuous segmental function in Cartesian space, in order to guarantee that angular displacement, angular velocity and angular acceleration curve is smooth and continuous, and forward kinematics was simulated by virtue of ADAMS software. At the same time, based on dynamic analysis, smooth and continuous driving torque curve of three actuated joints were obtained by force optimization method. This kind of trajectory planning method laid the foundation for redundant actuation control of the manipulator.

Abstract: Industrial robots are getting more and more applications in modern automated production, it’s a strong support to the development of manufacturing industry. Nowadays many domestic enterprises begin to do the robot R&D. We use mathematical software Matlab to make kinematics simulation of IRB1410 robot and succeed in verifying the justifiability of kinematics analysis.

Abstract: This paper presents a novel design of adjustable elliptical exerciser, which can adjust both stride and inclined angle. Firstly, we use a selected coupler curve of four-bar linkage to design a six-bar linkage. From the six-bar linkage, we investigate the parameters which affect the corresponding elliptical path and its inclined angle. By considering the way of adjusting the inclined angle, the final design becomes a 2-DOF seven-bar-eight-joint linkage. We use SolidWorks software to design this novel elliptical exerciser, and use CAE software to check the stresses and strains to ensure the strength of the members of this design. The prototype of this novel design of adjustable elliptical exerciser has been fabricated, and its feasibility has been confirmed.

Abstract: This paper describes the integrated design and techniques of the HAIBAO robot, an interactive service robot developed for Shanghai World Expo 2010. Compared with previous exhibition service robots, the HAIBAO robot has improved flexible motion ability, anthropomorphic interaction ability and intelligent cognitive and decision-making ability. In addition to both hardware and software system design, some key techniques including a four-wheeled omnidirectional mechanism and its motion control and compensatory algorithm, and multitask scheduling are introduced. During the Expo, which lasted 184 days, 37 HAIBAO robots successfully served tourists by providing information, photography services, hall guidance, conversation and various entertainment. Their robustness, stability, flexibility and friendliness were greatly commended.

Abstract: The space manipulator which is mounted on a space structure or spacecraft to manipulate space payloads is important for the on-orbit-servicing. Its manipulation tasks depend on its end-effector. The flexibility of the large space manipulator will result in residual vibration on its tip, and let the manipulator have poor capability of end positioning. To overcome the drawbacks mentioned-above, the end-effector needs strong capability of misalignment tolerance and soft capturing. On the base of these requirements and analysis, two kinds of end-effector schemes are presented and designed in detail. The essential performances are in comparison based on the results of dynamic simulations and experiments. Consequently, the conclusion is drawn that the steel cable-snared end-effector which captures the interface by winding the grapple fixture probe, is the best scheme that can combine the ability of soft capturing and great misalignment tolerance perfectly.

Abstract: This paper deals with the kinematics and dynamics of a novel bionic micro-robot based on the gastropod's locomotion principle. Profit from using friction control module, this robot has the ability to run smoothly in the biological lumen with impulsive flowing liquid. The locomotion principle is verified by experiments, on this basis, a mechanical model using space operator algebraic (SOA) method has been established to analyze the robot's kinematics and dynamics in different environments by mission simulation. Tests and simulations provide strong proofs for the structure design and motion control of the robot.

Abstract: China is now building the largest single dish radio telescope in the world in Guizhou province, which is called Five-hundred meter Aperture Spherical radio Telescope (FAST). A Stewart platform is introduced in FAST as an accuracy adjustable mechanism for feed receivers. The main purpose of this paper is to discuss dimension optimization design method of the Stewart platform based on three optimization objective functions. The optimization objective functions can reflect the operability and accuracy of the Stewart platform, and optimization design flow is presented according to the important degree of the three optimization objectives. Finally, a set of optimized parameters is obtained, and the study in this paper provides a basis for the coming optimization the feed support system for FAST in the next step.

Abstract: A new 4 DOF parallel mechanism with serial input limb is presented ——2UPS-RPU parallel mechanism, the limb with serial input is a less contrained active branched-chain,the number of its DOF is less than six,that is to say,the limbs not only transmitting driving force but also constraint force at the same time.Compared with traditional parallel mechanisms,the mechanism with serial input has greater number of DOF than the number of limbs and don’t lose the property of parallel mechanism. The inverse solutions to positions of the mechanism are modeled by inverse kinematic analysis in this paper, then the constraint conditions are established according to factors influencing the workspace of parallel mechanism,such as the limits of the hinge angle and the parallel link length.The workspace of 2UPS-RPU parallel mechanism can be obtained by using exetreme-boundary numerical algorithm in Matlab,the volume of workspace can be quantified by means of computation,and analyzing the impact of rod length ,circumradius of moving and fixed platform and motion pair rotation angle on the workspace.