Papers by Author: Fan Rang Kong

Abstract: One limitation on the performance of optical tweezers (abbreviated as OT) is the noise inherently present in each setup. Therefore, it is the desire to minimize and possibly eliminate the noise from the OT experiments. In this paper, a filter method based on wavelet analysis is proposed. At first we investigate the properties of OT outputs noise, and introduce the wavelet filtering method in simply. Following, we study on the OTs drift signal using different base: db4 and Haar. And also study on the signal using different filter algorithm: the soft,the hard threshold,and compulsive filter. These main conclusions based on foregoing analysis are reached: more larger the resolving scale is, more perfect the filtering effect is. The soft threshold value filtering effect is better than that of the hard threshold value filtering at the cost of calculation when the threshold value is same. The variance of the compulsive filtering is least when both the wavelet and the resolving scale are same for these filtering methods. For the compulsive filtering with same wavelets, the filtering effect of harr is better than that of db4 and the calculation of the former is fewer. Analysis the dynamic output of OT with different algorithm, it also shows that the effect of filter with the compulsive filtering is better than others. Accordingly, we found that applying the compulsive filtering with the Harr wavelet base and suitable resolving scale to the signal processing of OT outputs signal is helpful for the OT design and construction.

Abstract: The phenomenon of Doppler Shift leads to the difficulty for fault diagnosis of train bearings with a high moving speed. So the elimination of the Doppler shift should be implemented firstly. A Doppler Shift elimination method for the wayside acoustic signal is proposed. The instantaneous frequency estimation based on STFT was applied to attain the IF vector. According to the acoustic theory of Morse, the data fitting was then carried out to achieve the fitting IFs, with which the re-sampling sequence could be established to eliminate Doppler Shift. To demonstrate the validity of this method, an experiment with the synthetic signal containing several frequency components had been carried out. The results show that the re-sampled signal was revised without Doppler Shift.

Abstract: The noises with high level from the different positions of the train lead to the difficulty for extraction of the acoustic signal from the train bearings. Thus the de-noising should be carried out to eliminate the influence of the noises. A new de-noising method has been proposed based on the Doppler Shift. With the crazy climber detection algorithm, all the instantaneous frequencies could be extracted. According to the acoustic theory of Morse, the information of the position of these acoustic sources is revealed. Finally, the variable digital filtering was employed to remove the noises from the other positions of the train. A simulation on the signal containing with ten frequency components demonstrated the validity of this method proposed and the useful components of the signal were enhanced.

Abstract: This paper depicts the system design of an automatic golf collection robot. The robot is an intelligent system that consisted of three modules: the hardware module includes the mechanical structure and the electrical system; the control module processes the signals from the multiple sensors and outputs the instructions to navigate the robot; the vision module is used for recognition the golf balls from the grass background. The robot has been tested on the driving range, the basic functions of the robot have been achieved. The golf collection robot supersedes the human labor and shows a good application prospect.

Abstract: This paper depicts the system design of a robot that can recover the disrupted Rubiks Cube automatically. The robot is a typical mechatronics system consisted of the mechanical structure and the electrical system. The recovery procedures of the Rubiks Cube are shown as follows. Firstly, the color recognition of each face of the Rubiks Cube is conducted with an industrial CCD camera. Then the embedded recovery algorithm is called, and the recovery steps are achieved. Finally, the pneumatic manipulators are driven by the pressurized air controllable via an electrical relay array, the Rubiks Cube is recovered step by step following the recovery sequences. The Rubiks Cube robots have been exhibited in several science museums in China, they are well welcomed by the audiences.

Abstract: A kind of mini underwater robot is introduced in this artical. Aim at the situation of shallow water area(5m~30m)，we analyzed and designed the structure of the whole robot pertinently, and calculated the underwater movement resistance, which thereby could give theoretical support on the choice of thrusters. The robot detects the underwater situation effectively by high definition camera that installed in the front of the robot, and achieves lifting and turning movement though 3 propellers. The manipulator installed in above of the robot could grab underwater objects effectively.

Abstract: Hydraulic technology is applied to the hydraulic clamp. The combination of mechanical and hydraulic can make hydraulic clamp smart and compact, meanwhile, it achieves a great deal of additional power. The effect of hydraulic force increasing is entirely feasible. The principle, the mechanical structure and structure modeling of the multi-function hydraulic clamp are described in this paper. By optimizing the product design, the structure is more reasonable and compact ,the pressure of hydraulic clamp is adjustable.

Abstract: The key to fault diagnosis of rolling element bearing is how to find typical characteristic frequencies from low SNR mixed signals. Jointing Continuous Wavelet Transform (CWT) with Independent Component Analysis (ICA)，this paper proposes a method to select wavelet scales with iso-interval frequency and analyze envelope spectrum of independent signal to diagnose the fault of rolling element bearing. Finally, the effectiveness of this method has been verified by practical signal of rolling element bearing.

Abstract: In this paper, objective design phase for beginning end of product design process is studied and the procedures and steps of object design is described. Sources of finding design objects and methods, information collection and processing of design object are studied. Simultaneously, several criterions are designed to judge feasibility of design object, such as social environment criterion, economic cost criterion, technology criterion, time criterion, value criterion etc.. Computer aided screening and evaluation is realized during objective design. Finally, the template of expressing design object is given.