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The position of focal plane will be changed because of temperature fluctuation and vacuum environment. In order to make the telescope work well, a focusing mechanism is needed. To majority of large space-based telescopes, the general way to do this would be to use a reflector, which was located in the backfocal distance. One of typical schemes of this mechanism was introduced, however, because of...
Uninhabited Aerial Vehicle(UAV) has been developed quickly for decades and a new kind of VTOL(Vertical Take-Off and Landing)UAV which is called Ducted-Fan Uninhabited Aerial Vehicle attracts more and more attention. This paper presents a new structure of the ducted-fan UAV. In this vehicle, the actuator system consists of four rotary cylinders which are symmetrically installed at bottom of inside...
A new Robot Terrain Inclination model (RTI model) extracted from laser scanner data is proposed in this paper. The RTI model can be used to evaluate the terrain traversability or assist localization and mapping for outdoor mobile robot. The paper presents the segmentation of the terrain points and the non-terrain points and the extraction of RTI model. Experiments were carried out to demonstrate the...
This paper studies the actuator of biomimetic ray based on the Ionic exchange polymer metal composites (IPMC). The IPMC sample is prepared by chemical method and the preparation process is introduced. An IPMC performance test system is constructed to investigate the relationships between the output response of IPMC and the input stimulation signals. According to the difference of input signals, performance...
In this paper, we propose a new velocity constraint type for Redundant Drive Wire Mechanisms. The purpose of this paper is to demonstrate that the proposed velocity constraint module can fix the orientation of the movable part and to use the kinematical analysis method to obtain the moving direction of the movable part. First, we discuss the necessity of using this velocity constraint type and the...
In this paper, we propose a vision-based weld line detection system with cross structured light (CSL) and Hidden Markov Model (HMM). Our consideration is that the laser stripes projected by CSL can reflect the convex shapes of weld lines, capture horizontal and vertical weld lines simultaneously and are insensitive to illumination changes. The Hidden Markov Model filters out various noises on the...
This paper improves the method for the estimation of modal parameters from free decay response of a structural system using continuous wavelet transform (CWT). The CWT of free decay response is investigated especially for the case when closely spaced modes need to be analyzed. A robust iteratively reweighted least-squares (IRLS) linear regression method is introduced to fit wavelet amplitude and phase...
In recent years, a number of stereovision-capable devices emerge as travel aids for the visually impaired. However, these head-mounted devices are bulky and can only assist a user to avoid obstacles. In this paper, we detail a wearable stereovision system that can not only help avoid obstacles, but also stream real-time video feed via the 3G network. This wearable device is composed of an eyeglasses...
Cavity adjustment is a critical step for manufacturing laser gyro. Location relation of the laser facula and the aperture images should be detected to provide control information for the movement of the cavity adjustment mechanism. According to the image features, a sequence image variance method is proposed to segment the laser facula image, and maximum variance between clusters method (Ostu algorithm)...
There are complexity and cascading failure in ship fire-fighting system. According to the characteristics of ships, set pair analysis is used from overall system to subsystems. This paper analyzes the failure factors and establishes a cascading failure hierarchy correlative model of this fire-fighting system. Considering occurrence uncertainty such as fuzzy state, random state and medium state of...
In this paper, a method is proposed to reduce the impact of delay time and packet loss, because they have serious effects on serviceability of the remote operation mechanical system. The stability of a nonlinear bilateral teleoperation system with force feedback which has the similar combination of structure is discussed, and the system stability conditions are studied. The self-adaptive algorithm...
SLAM based on distributed particle filter diminishes the calculation quantity with an acceptable result. However, the accuracy of the distributed particle filter is not ideal and the distribution of the particles is not adjusted with the observations. To tackle with this problem, this paper used distributed Unscented Particle Filter (UPF) arithmetic to estimate the states of SLAM. The distributed...
In recent years, aiming at the increasingly serious pipeline damages because of the artificial factors, we investigate the characteristic of seismic signals and develop a monitoring and pre-warning system for security of pipelines based on multi-seismic sensors. There are many sensors and processing modules to acquire the seismic signals generated by the ground targets. If these modules all transmit...
Calibration accuracy of the inertial navigation system (INS) has a great influence on navigation accuracy of the inertial navigation system. Currently the turntable being used has reached a high accuracy, the three axis turntable coordinate system is usually regarded as orthogonal coordinate system referenced by gyro misalignment, so the nonorthogonal error of turntable is not taken into account in...
Considering such problems as the complex coalmining geological conditions, deprivation of test data for two dimension seismic prospecting, the low sensibility and poor stability as well as repeatability for traditional seismometers in many Yunnan coalfield places, this paper puts forward a method for carrying out two dimension seismic prospecting based on the real-time data acquisition system of intelligent...
Industrial snap assembly processes remain largely a manual task. Much of the research in snap assembly has not sought to design strategies and controllers according to the class of snap-fastener used. Three fastener types are used in manufacturing: cantilever, torsional, and annular snaps. As a first step in solving the snap automation problem, sought to devise a force control strategy that could...
This paper presents an open embedded hardware and software architecture for industrial robot control. Open hardware refers to open source IP-core provided by the authors, while open software implies the use of open source software, specifically Linux and OROCOS [1]. Embedded implies integration of various functional blocks on one System-On-Chip board, for data acquisition, computation and control...
A new smooth online near time-optimal trajectory planning approach is proposed to reduce the computation cost compared to traditional dynamics trajectory planning method. The robot path is expressed by a scalar path coordinate s. The joints torque bounds and speed bounds are transformed into the s-s plane, which can generate the limitation curves of pseudo-velocity. The maximum pseudo-velocity curve...
In order to suppress vibration of flexible robots, the concept of controllable local degree of freedom is proposed and a physical model of flexible robot with single controllable local degree of freedom is built, with a flexible main chain and a rigid branch link. The dynamic model is established using Kane method and assumption modal method. Numerical simulation is carried out and the theoretical...
Manipulating deformable linear objects (DLOs) is much challengeable as the uncertainty resulting from oscillation of DLOs may cause failure in the operation. In this paper, we proposed a position-based control strategy to eliminate the vibration at the end of DLOs. The simplified dynamic model of a DLO is obtained by local linearization, Schur decomposition of matrices and linear transform of variable...
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