Table of Content

    01 January 2018, Volume 52 Issue 1 Previous Issue    Next Issue
    A Fast Method to Build Elevation Terrain Grid Map Using V-Disparity
    YUAN Weia,b,YANG Minga,b,DENG Liuyuana,b,WANG Chunxiangc,WANG Binga,b
    2018, 52 (1):  1-6.  doi: 10.16183/j.cnki.jsjtu.2018.01.001
    Abstract ( 901 )   Save
    Automatic vehicle must perceive the off road 3D environment when it is moving on the off road. The terrain can be rebuilt by stereo vision, but it may get poor efficiency and accuracy if it is rebuilt directly. This paper uses V-disparity to preprocess the disparity image to get effective reconstruction regions and remove the non accessible area from disparity image. The inertial measurement unit (IMU) and speedometer are fused to update the elevation grid map, which is smoothed by using medium filter and areas grid filter. Thus, a 3D terrain elevation grid map can be rebuilt rapidly. The method could increase significantly the efficiency and accuracy of reconstruction since it only rebuilds the effective reconstruction region. Test results show that this method has good real-time performance and high accuracy.
    References | Related Articles | Metrics
    A Convolutional Neural Network-Based Method for 3D Object Detection
    LI Yangyang,SHI Licheng,WAN Weibing,ZHAO Qunfei
    2018, 52 (1):  7-12.  doi: 10.16183/j.cnki.jsjtu.2018.01.002
    Abstract ( 1508 )   Save
    We used random sample consensus and distance cluster to segment object instead of sliding windows. In recognition step, we designed a new algorithm to extract point cloud feature. Firstly, the point cloud of objects was converted to depth map, then k-Means is applied to learn features from random patches. The learned feature can be used as the convolutional neural network (CNN) filters and convolved over the input image to extract convolutional feature. The presented method was tested by using two public datasets. The results showed that feature learned by single layer CNN can achieve higher recognition rate than artificially designed feature.
    References | Related Articles | Metrics
    Mobile Robot Seamless Localization Based on Smart Device in Indoor and Outdoor Environments
    ZHAO Guoqia,b,YANG Minga,b,WANG Binga,b,WANG Chunxiangc
    2018, 52 (1):  13-19.  doi: 10.16183/j.cnki.jsjtu.2018.01.003
    Abstract ( 981 )   Save
    A multiple model which is suitable for indoor and outdoor application is presented based on loca-lization algorithm. Due to big difference between indoor and outdoor environments, there hardly exists a general localization algorithm for the two environments. In this work, a switched scheme is proposed to deal with this problem. Because of nonlinearity in measurement, method based on particle filtering is adopted for the mode matching filter. In time update, movement between two consecutive frames is provided by an inertial measurement unit (IMU). In measurement update, global positioning system (GPS) and iBeacon are used as observers in outdoor and indoor, respectively. A weighted error compression ratio which can adjust Markovian parameters online is proposed to deal with mismatch of competition model resulted by model switching frequently. Thus the localization precision can be guaranteed in situation of frequent switch between indoor and outdoor. Experimental results demonstrate precision and robustness of the proposed method which outperforms some state-of-the-art methods (e.g., IMM-PF, single model algorithm, IMM-KF, etc), especially when observation noise exists.
    References | Related Articles | Metrics
    Design and Locomotion Properties of a Multi-Airbag Bionic Soft Robot
    WANG Jiangbei,FANG Yeyang,TONG Xin,ZHANG Shuai,FEI Yanqiong
    2018, 52 (1):  20-25.  doi: 10.16183/j.cnki.jsjtu.2018.01.004
    Abstract ( 1663 )   Save
    A multi-airbag bionic soft robot is designed, which consists of several connected airbags sitting on a two-layer base. The robot bends when airbags are inflated. Two friction plates are mounted at the bottom to generate different friction forces in the front and back to make the robot move forward. The locomotion analysis is completed and structure of the robot is improved according to the finite element analysis of internal stress and strain by using software ANSYS. By using the Yeoh model, dynamics analysis of the moving process is finished and the non-linear relationship between pressure inside the airbags and stride length of the robot under theoretical conditions is obtained. Finally, an experiment is conducted to verify the moving mode of the bionic soft robot. Results indicate that the experimental stride length is 19.25mm, which is basically consistent with the theoretical one 22.85mm.
    References | Related Articles | Metrics
    3D Map Reconstruction in Indoor Environment Based on Normal Distribution Transformation Under Gravity Constraint
    QI Mingxua,b,YANG Minga,b,WANG Chunxiangc,WANG Binga,b
    2018, 52 (1):  26-32.  doi: DOI: 10.16183/j.cnki.jsjtu.2018.01.005
    Abstract ( 665 )   Save
    A method for offline reconstruction of indoor 3D map is proposed based on an improved normal distribution transform (NDT) algorithm. First, a constraint in the gravity direction is incorporated into a 3D NDT, so that map deformation in extra dimensions is rectified. Then a cyclic gradient matching scheme is proposed to deal with the matching error resulted from scarce overlap between consecutive frames. Finally, a graph optimization is adopted in the back-end map construction. By using a swinging laser, experiments validate its performance and high accuracy.
    References | Related Articles | Metrics
    A Lane-Level Positioning Method Based on Vision and Millimeter Wave Radar
    ZHAO Xianga,b,YANG Minga,b,WANG Chunxiangc,WANG Binga,b
    2018, 52 (1):  33-38.  doi: 10.16183/j.cnki.jsjtu.2018.01.006
    Abstract ( 1619 )   Save
    A lane-level positioning method based on vision and millimeter wave radar is proposed. A camera is used for lane recognition with circular curve model and a millimeter wave radar is used for road curb re-cognition by detecting the stationary railways alongside. Lane-level positioning is then calculated by comparing the relative distance of lane and curb with the road prior information obtained from a low precision global position system (GPS). The results show that the lane-level positioning method proposed in this paper can achieve good positioning accuracy in city and highway scenes.
    References | Related Articles | Metrics
    Optimization and Realization of Wireless Capsule Robot
    SHEN Yue1,JIANG Zhihua2,YAN Guozheng1,KE Quan1,WANG Yongbing1
    2018, 52 (1):  39-44.  doi: 10.16183/j.cnki.jsjtu.2018.01.007
    Abstract ( 976 )   Save
    A reducer is designed for clamping mechanism to provide sufficient expanding force and the relatively slow expanding speed. The reduction ratio of the reducer is up to 489 to ensure a large output torque. In addition, the optimization experiment of the wireless power receiving coil is carried out. The influence of the dimension of the one-dimensional receiving coil and the number of winding wires on the receiving effiency is analyzed. The results show that the larger the core thickness is, the higher the receiving efficiency is, considering the total outer diameter of the core and the winding.
    References | Related Articles | Metrics
    Self-Collision Detection and Motion Planning for Dual-Arm Robot
    WU Changzheng1,YUE Yi1,2,WEI Baochen1,LIU Dianfu3
    2018, 52 (1):  45-53.  doi: 10.16183/j.cnki.jsjtu.2018.01.008
    Abstract ( 1855 )   Save
    A method based on geometric distance of space vector is proposed for the self-collision detection in motion planning of dual-arm robots. In terms of this, a linear repulsion force field which is improved from the artificial potential field method is used to describe the position relationship and collision quota among the links. Then a novel self-collision-free motion planning is derived by combining with the linear form of repulsion potential field. Compared with the traditional artificial potential filed planner, the improved linear force field can directly act as an operator to plan the trajectory of the dual-arm robot with properties that are simple and easy to be handled. Finally, a case study demonstrates the effectiveness of the motion planning algorithm with the real parameters of a dual-arm robot.
    References | Related Articles | Metrics
    Deviation Propagation Model and Optimization of Concentricity for Aero-Engine Rotor Assembly
    DING Siyi,JIN Sun,LI Zhimin,WEI Zhenqi,YANG Fuyong
    2018, 52 (1):  54-62.  doi: 10.16183/j.cnki.jsjtu.2018.01.009
    Abstract ( 1132 )   Save
    Using robust eigenvalue method (REM), deviation propagation model was built to describe the relationship between the plane parameters and the concentricity of high pressure compressor (HPC) rotors in aero-engine assembly through experiments. The calculated values and measured values of parts eccentricity and circle run-out of mounting face were compared and the results verified the reliability of the model. In addition, contribution analysis was realized. In order to effectively improve the concentricity of HPC rotors, genetic algorithm (GA) was adopted to determine the optimal installation angles for each part. The results showed that the proposed REM-GA method was suitable for continuous process of stacked assembly and could improve the concentricity of each part by over 50 percent, and the obtained optimal installation angles were 6.225, 3.422 and 5.983 rad respectively.
    References | Related Articles | Metrics
    Heuristic Algorithm-Based Initiation Method of Probability Hypothesis Density Filter for Target Tracking
    LI Tantan,LEI Ming
    2018, 52 (1):  63-69.  doi: 10.16183/j.cnki.jsjtu.2018.01.010
    Abstract ( 929 )   Save
    The heuristic algorithm-based initiation method under the probability hypothesis density (PHD) framework is suggested, i.e., the constraints which involve velocity, acceleration and angle of maneuvering targets are adopted in a sliding window, and the most unwanted newborn intensity can be removed. Simulation results show that the proposed method can effectively reduce the intensity quantity of newborn targets, and the computational cost is reduced. Meanwhile, estimation accuracy involved state and target number is enhanced explicitly.
    References | Related Articles | Metrics
    Force Feedback Control for Assistive Mode Training of the Wrist Rehabilitation Robot
    WANG Yiqing a,XIE Le a,b,HONG Wuzhou b
    2018, 52 (1):  70-75.  doi: 10.16183/j.cnki.jsjtu.2018.01.011
    Abstract ( 1119 )   Save
    A three degrees of freedom (DOFs) wrist rehabilitation robot and the assistive control system with the force feedback function are designed. The assistive force provided by motors is determined according to the force/torque detected from the patient. The system ensures the patient can keep the same force/torque in assistive training. Compared with the electro-encephalogram (EEG) or surface electromyography (sEMG), the force feedback possesses many advantages such as high operability, accuracy, stability and low cost. Three closed loops with current, velocity and current system are applied in the control system. Proportional-integral (PI) regulator is applied in both current and velocity loops, and sliding variant structure regulator is adopted in the position loop, which effectively improves the accuracy and robustness of the system. System simulation has proved the validity of this control system.
    References | Related Articles | Metrics
    Tactile Force Sensor of Underwater Dexterous Hand Based on Micro Electromechanical System
    ZHANG Jianjun1,LIU Weidong1,ZHANG Yiwen2,TANG Weijiang1,2
    2018, 52 (1):  76-82.  doi: 10.16183/j.cnki.jsjtu.2018.01.012
    Abstract ( 1009 )   Save
    In order to achieve the position determination and force tactile perception in underwater dexterous hand grasping target under deep water environment, an array of tactile force measurement sensor is designed. The silicon cup is used as the force sensitive core, the tactile force measurement of the static pressure vector superposition of water is realized by the capsule differential pressure structure, and the influence of the static pressure of water on the tactile force measurement is eliminated. The analytical solution for the deformation and stress of silicon cup square bottom is analyzed by the elastic mechanics and shell theory. The results show that the tactile force sensor of underwater dexterous hand achieves the tactile perception and position determination of the target gripping. The capsule differential pressure structure makes the tactile force sensor eliminate the effect of the static pressure. The silicon cup measurement structure has the advantages of high sensitivity, small error, and high output characteristics of stress.
    References | Related Articles | Metrics
    Model-Based Marker-Less 3D Tracking Approach for Augmented Reality
    WANG Yue,ZHANG Shusheng,HE Weiping,BAI Xiaoliang
    2018, 52 (1):  83-89.  doi: 10.16183/j.cnki.jsjtu.2018.01.013
    Abstract ( 1470 )   Save
    To tackle the huge searching space and few texture feature points on the object surface problem, we propose a novel method that combines model-based tracking and natural feature tracking for fast and robust camera pose calculation. The proposed method first adapts the state-of-the-art template matching method LINE-MOD into a scale invariant descriptor to recognize the target object and obtain the key-frame that is similar to the current viewpoint. Therefore, it greatly reduces the search space for pose refinement method and improves the searching speed. After that, the keyframe obtained from template matching stage is exploited to refine the tracking accuracy. In order to avoid tracking jitter and improve tracking accuracy and speed, RPnP algorithm is incorporated into our system. The experimental results and performance evaluations demonstrate that our method is fast, accurate and robust for 3D registration and tracking even under partial occlusion, and the tracking speed can reach 30 frame/s.
    References | Related Articles | Metrics
    Logical Circuit Accelerated Computing for Phase Change Memory Based Storage System
    LI Gezi1,CHEN Xiaogang1,CHEN Houpeng1,JIAO Shengpin2
    2018, 52 (1):  90-95.  doi: 10.16183/j.cnki.jsjtu.2018.01.014
    Abstract ( 955 )   Save
    A phase change memory (PCM) based storage system with novel logical device is proposed, and it can off-load compute-intensive tasks from sever to the storage. In such a way, the proposed PCM-based storage system can avoid extra data transfer and improve efficiency of data processing with parallelism capability of logical device. Moreover, PCM promises to increase the overall system performance due to its unique features. Experimental results demonstrate that the proposed system is vastly superior to the traditional way.
    References | Related Articles | Metrics
    Artificial Bee Colony Algorithm with Gradually Enhanced Exploitation
    DU Zhenxin1,2,HAN Dezhi2,LIU Guangzhong2,JIA Jianxin2
    2018, 52 (1):  96-102.  doi: 10.16183/j.cnki.jsjtu.2018.01.015
    Abstract ( 867 )   Save
    Concerning the issue that solution search equation of artificial bee colony (ABC) algorithm does well in exploration but badly in exploitation, a new method is proposed to gradually enhance the exploitation ability of ABC algorithm. In the proposed algorithm, employed bees learn from the local best individuals and proportion of the local best individuals is gradually enhanced. Onlooker bees learn from the local best and global best individuals and proportion of the global best individual is gradually enhanced. A forementioned measures can effectively balance the exploration and exploitation ability of ABC algorithm. The experiments are conducted on 36 benchmark functions, including CEC2014 problems. The performance of the proposed algorithm outperforms those of ABC with neighborhood search (ABC-NS) and composite DE (CoDE) algorithms significantly.
    References | Related Articles | Metrics
    Vehicle Recognition in Acoustic and Seismic Networks via Collaboration Representation
    WANG Rui,LIU Bin,ZHOU Tianrun,YANG Yu
    2018, 52 (1):  103-110.  doi: 10.16183/j.cnki.jsjtu.2018.01.016
    Abstract ( 866 )   Save
    Aiming at the defects of the current recognition methods using single signal, we propose a vehicle recognition method based on the collaboration representation of acoustical and vibrative signals. Firstly, Mel-frequency cepstral coefficients (MFCCs) are used to extract the acoustical and vibrative features of vehicles. Then, multitask training of classification is carried out separately by two kinds of signal features. Finally, the reconstruction error of multitask collaboration representation is obtained through the signal features and the target is classified according to the reconstruction error. Experiments indicate that this method has better classification effect and higher recognition efficiency, compared with the existing methods.
    References | Related Articles | Metrics
    Algorithms for Degree Reduction of Interval q-Bézier Curves
    LIU Zhi1,LV Yanyan1,LIU Xiaoyan2,ZHANG Li1
    2018, 52 (1):  111-119.  doi: 10.16183/j.cnki.jsjtu.2018.01.017
    Abstract ( 955 )   Save
    Interval q-Bézier curves are presented using a generalized Bernstein basis and the problem of degree reduction approximation of them is studied. We propose three different methods, namely, perturbation method, best uniform approximation method and constrained best uniform approximation method based on Chebyshev polynomials. The explicit representation of bounding error of each method is derived. The advantages and disadvantages of these methods are discussed by several numerical examples. These examples show that the best uniform approximation algorithm provides much tighter approximation interval curves than the perturbation method.
    References | Related Articles | Metrics
    A Optimal Guaranteed Cost Control of Networked Multi-Rate System
    WANG Zhiwen,LI Xuan,ZHU Chaoqun
    2018, 52 (1):  120-126.  doi: 10.16183/j.cnki.jsjtu.2018.01.018
    Abstract ( 864 )   Save
    In multi-rate networked control system (NCS), the sampling period of sensor, controller and actuator shows the characteristics of asynchronous sampling uniformity. The whole system is no longer a single-rate sampling mode, and it is more suitable for the essential characteristics of NCS and control requirements. A networked multi-rate input control system with network-induced time-delay and output prediction is illustrated in this paper. A dynamic output feedback controller is designed to obtain the optimal guaranteed cost control of the system, and the stability of this closed-loop control system is proved by linear matrix inequality (LMI) method. Finally, a numerical simulation is given to demonstrate the effectiveness of the proposed control system.
    References | Related Articles | Metrics