Applied Mechanics and Materials Vols. 284-287

Abstract: Marine environments cover most of the earth’s surface, and average depth more than 3800m. It is rich in biological resources and mineral resources. With the depletion of land resources, marine resources development and utilization is increasingly apparent. However, accompanied by the development of marine resources such as oil, natural gas from offshore extension to the deep ocean, Remotely Operated Vehicle (ROV) for its safety, high efficiency, large range of operating depths, work long hours, is increasingly becoming the development of marine resources important tool. In this study, the science/work-class ROV which design by Taiwan Ocean Research Institute (TORI) and Built from Perry is discussed.

Abstract: In recent years, the development of fuel cells has proceeded rapidly, and so the reforming of methanol to produce hydrogen has become a serious problem. Supplying hydrogen from a micro methanol reformer to fuel cells is an important topic. The structure of a micro flow channel must support the transfer of external heat to the reform reaction, facilitating the diffusion of methanol vapor into the catalyst layer, increasing the rate of transfer of hydrogen. In this investigation, the micro-electro-mechanical systems (MEMS) technique is utilized to fabricate micro pressure, temperature and flow sensors. Polyimide film (PI) exhibits high temperature resistance and stress corrosion resistance, and is adopted herein as a flexible substrate. In future work, such micro sensors will be embedded in a micro methanol reformer for in-situ diagnosis.

Abstract: The article designs the multiple pattern formation controls of the multi-robot system according to two arms’ gesture of the player, and uses flood fill searching algorithm and A* searching algorithm to program the motion paths. The inertia module detects two arms’ gesture of the player. We use the inertia module to be embedded in the two arms, and use mobile robots to present the movement scenario of pattern formation exchange on the grid based motion platform. We have been developed some pattern formations applying in the war game, such as rectangle pattern formation, long snake pattern formation, L pattern formation, sword pattern formation, cone pattern formation and so on. We develop the user interface for variety pattern formation exchange according to the minimum displacement on the supervised computer. The mobile robot receives the command from the supervised compute, and transmits the status of environment to the supervised computer via wireless RF interface. Players can use variety arms’ gesture to control the multiple mobile robots to executed pattern formation exchange. In the experimental results, the supervised computer can decides the arm gesture using fusion algorithms. Mobile robots can receive the pattern formation command from the supervised computer, and change the original pattern formation to the assigned pattern formation on the motion platform, and avoid other mobile robots.

Abstract: In complex systems like flight control systems etc., reliability is as important as performance. In order to improve the reliability of flight control system (FCS), the fault- tolerant technique was adopted. Three parts of the FCS which are Flight Control Fault Tolerant Computer, Redundancy sensor and Servo-actuator have been explored. The key techniques have been solved, such as Redundant Disposition, Synchronism of the Redundant Channels, Data link and Communication of Channels, etc. The experimental results show that the system meets with the fly control system’s demand of reliability.

Abstract: For most quadruped robots, their waist joints can usually pitch or yaw, but cannot roll. Thus, their gaits can only be simulated by a simple motion model based on single-legged mechanisms. When pandas move on their four feet, they swing their hips and rear legs from side to side. Thus, the purpose of this study is to develop a quadruped robot which is equipped with a waist joint of one degree of freedom (DOF) for rolling so as to imitate the waist-swinging motion of a real panda. This research starts at editing the predetermined motion conditions with lengths of all panda body parts and the mechanism model with corresponding degree-of-freedom in the CAE software. The related simulation parameters of leg motions are acquired as a reference for gait controls. The quadrupedal walking process was tested in simulators to verify important design variables and simulation validity was also verified on the actual panda robot after their buildup. With this approach, this study has effectively and successfully developed a panda robot with a waist joint that can roll.

Abstract: This paper proposes the parameters estimation and position control of an induction motor drive by using the composite adaptation scheme. First, in the rotor reference frame, the input-output linearization theory was employed to decouple the mechanical rotor position and the rotor flux amplitude at the transient state. An open-loop current model rotor flux observer was utilized for estimating the flux, and then the adaptive laws for estimating the rotor resistance, moment of inertia, viscous friction coefficient, and load torque. The passive properties of the flux observer, rotor resistance estimator, and composite adaptive position controller were analyzed based on the passivity theorem. According to the properties, the overall position control system was proved to be globally stable without using Lyapunov-type arguments. Experimental results are finally provided to show that the proposed method is robust to variations of the motor mechanical parameters, rotor resistance, and load torque disturbances. Moreover, good position tracking response and characteristics on parameter estimation can be achieved.

Abstract: A model-free adaptive sliding controller with fuzzy compensation is proposed for a piezo-actuated micro-drilling process control in this paper. Due to the system’s nonlinear and time-varying characteristics, this control strategy employs the functional approximation technique to establish the unknown function for releasing the model-based requirement of the sliding mode control. In addition, a fuzzy scheme with online learning ability is augmented to compensate for the finite approximation error and facilitate the controller design. The important advantages of this approach are to achieve the sliding mode controller design without the system dynamic model requirement and release the trial-and-error work of selecting approximation function. The Lyapunov direct method is applied to find adaptive laws for updating coefficients in the approximating series and tuning parameter in the fuzzy compensator to guarantee the control system stability.

Abstract: Legged living creatures can move on any kinds of terrain with good adaptability. They read the terrain conditions and repeat inherent or acquired obstacle crossing sequences, which can be imitated mechanically for the design of a Quadruped. For the prototype model and the step, four corner distances are determined according to the desired body angle and the continuous locomotion sequences are determined. Also, the requirements to satisfy three conditions for step-down are introduced, which makes it possible to determine the exact number of steps in the second phase of step-down. Since step-up is the reverse of step-down, all the governing parameters are the same and the locomotion sequences of step-down are also the reverse of step-up, except for the case of walking-down by gravity. The dimensions of a suggested quadruped are used to calculate the crossing performance for the purpose of comparison.

Abstract: The novel FPGA (Field Programmable Gate Arrays) can embed a processor to be an SoPC (System-on-a-Programmable-Chip) environment which allows user to design the applications by mixing hardware and software. Therefore, a motion control system of wafer-handling robot based on the SoPC technology is presented in this paper. In FPGA, it is consists of two modules. The first module is Nios II processor which is used to realize the motion trajectory planning and three-axis position/speed controllers by software. The program developed in Nios II processor uses C language. The second module is presented to implement three-axis current vector controllers by hardware, and VHDL (VHSIC Hardware Description Language) is applied to describe the controller behavior. Therefore, a fully digital motion controller for wafer-handling robot, such as three current vector controllers, three position/speed controller and one trajectory planning are all can implemented by a single FPGA chip. Finally, an experimental system constructed by an FPGA experimental board, one three-DOF wafer-handling robot, and three inverters is set up to demonstrate the correctness and effectiveness of the proposed SoPC-based motion control system of wafer-handling robot.

Abstract: This paper presents a practical real-time visual navigation system, including a vision system, a particle filter (PF) based localization system, and a path planning system, for humanoid robots in an indoor environment. A neural network (NN) converter system is used to solve the image distortion problem. The monocular vision system detects objects of interest in the scene, calculating their position in the image, and converting the position in the image to real world coordinates. The PF localization system estimates the current position by the robot’s motion model and corrects the estimated position by using feedback from the data gathered by the vision system. The path planning system determines the next motion based on the result of the localization system. This paper uses a tree-like path planning method which not only guides the robot to the destination but also avoids obstacles at the same time. The navigation method allows a user to assign several different target destinations to the robot simultaneously. The proposed method is implemented on a humanoid robot “ROBOTIS DARwIn-OP”, an open platform humanoid robot. The effectiveness of the system is demonstrated in an empirical evaluation.