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Targeting at the nonlinear, time-varying characteristics of terrain detector-milling cutting depth electro-hydraulic servo system in soil milling collection machines, this paper proposed the PID control menthod in BP neural network of terrain detector - milling cutting depth system and designed PID controller in BP neural network and conducted simulation analysis by programming with Matlab. The results show that, when compared with conventional PID control, BP neural network compounded with PID control would enable the system better dynamic performance and follow-up characteristics, therefore, it is an effective control strategy.

Service robots are increasing significantly, as they are playing a key role in our city-life. This paper depicts the system design of a beverage-sale robotic system named BSR. BSR can sale beverage such as Coca Cola, beers and Sprite to the clients automatically, working as a human seller. The robotic system can also play the role of a casher doing cash in and check out. In this paper, the hardware design including the mechanical structure and the electrical system are introduced firstly. Then, the control strategy is proposed. BSR has been exhibited in a science museum in China and it is well welcomed by the audiences.

This paper depicts the system design of a basketball-playing robot named BPR. BPR is a wheeled mobile robot equipped with a 3-DOF manipulator and a mechanical claw. The robot can grasp one basketball and then dunk under the players remote control. In this paper, the hardware design including the mechanical structure and the electrical system are introduced firstly. Then, the kinematic analysis of the manipulator is proposed to decide the manipulators posture control. Finally, simulation of the manipulator is implemented in ADAMS to verify the design efficiency of posture planning. BPR has been exhibited in a science museum in China and it is well welcomed by the audiences.

Weak signal detection has attracted many researchers attention all over the world. Most of the methods focus on the single frequency signal. This paper introduces a new method to separate the weak double-frequency signal overwhelmed in heavy background noise. The cascaded stochastic resonance (SR) system (CSRS) is composed of a bistable SR model in the first stage and a tristable one in the second. Based on the characteristic of the SR system, we can amplify the useful signal of high frequency using twice sampling technic to make its parameters matching the requirements of the system. In our proposed cascade stochastic resonance system, we highlight the appointed frequency from high to low successfully with adjusting the twice sampling multiple and the high pass filter band. The signal composition of different frequency can be obtained from the systems two stage output. Simulated experiment validates the CSRSs availability in weak double-frequency signal separation and also its promising application in a more complex mixed signal.

Innovative design refers to give full play to the designer's creativity, using humans existing science and technology achievements (the theory, method and technology principle, etc) to find innovative ideas, and design a scientific, creative, novelty and practicable product. With the rapid development of modern knowledge in many industries, having higher market occupancy also becomes more and more difficult. So it requires immediate talent team having enough innovative ability and innovative ideas. [1, Innovative design methodology, the objects of this research, makes the engineering design divided into four processes that are Object Design, Conceptual Design, Parameter Design and Optimal Design. In the process of designing new products, a substantial amount of professional knowledge, and reasonable selection of the knowledge which is mastered, using the knowledge, getting more familiar with the four innovative processes are all very important to innovative design and also the development of new products. And here, in the process of Sports Equipment Design, this design methodology can make the designers more inspired and having a more distinct thought.

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.

In wayside fault diagnosis of train bearings, the phenomenon of Doppler distortion in the acoustic signal of moving acoustic source acquired with a microphone leads to the difficulty for signal analysis. In this paper, a new method based on Dopplerlet transform and re-sampling is proposed to eliminate the Doppler distortion of multiple acoustic sources which provide a reference for wayside fault diagnosis of train bearings. Firstly, search the parameters space to find the primary functionsDopplerlet atoms. According to the Morse acoustic theory, the instantaneous frequency of the Dopplerlet atom which we choose to remove Doppler distortion of the corresponding acoustic source can be acquired. Then, the re-sampling sequence can be established in time domain. Through the resample, the Doppler distortion can be removed. In the end of this paper, an experiment with practical acoustic signals is carried out, and the results verified the effectiveness of this method.

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.

The research in bearing fault diagnosis has been attracting great attention in the past decades. Development of feasible fault diagnosis procedures to prevent failures that could cause huge economic loss timely is necessary. The whole life of the bearing is also a developing process for some sensitive features related to the fault trend. In this paper, a new scheme based on ensemble empirical mode decomposition (EEMD) and support vector regression (SVR) to conduct bearing fault degree recognition is proposed. This analysis first extracts the sensitive features from the intrinsic mode functions (IMFs) produced by EEMD which is a potential time-frequency analysis method, and then constructs an intelligent nonlinear model with input feature vectors extracted from the IMFs and defect size as output. Through validation of experimental data, the results indicated that the bearing fault degree could be effectively and precisely recognized.

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.

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.

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.

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.

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.

A novel optical scanner excited by a torsional piezoelectric fiber actuator is presented. The device consists of a piezoelectric fiber actuator generating torsional and longitudinal vibrations simultaneously and a specially designed metal frame transforming the two vibrations to orthogonal deflections of the mirror. Theoretical and experimental studies were performed on the structure. The changing trends of the vibration modes and resonant frequencies were obtained from finite element simulations. Samples with 1 mm × 1 mm mirrors were fabricated from PZT hollow fibers with a diameter of 1 mm and a stainless steel sheet with a thickness of 50 μm. A horizontal scanning angle of 17.9° and a vertical scanning angle of 2.6° were achieved at 6780 and 10,330 Hz under an applied voltage of 400 V p–p .

A new kind of piezoelectric pump utilizing centrifugal force directly is introduced in this paper. It uses a metal tube to act as both the wobbling part and the liquid channel. Several piezoelectric elements attaching to the metal tube are used as the actuators to push the metal tube to wobble at its resonant frequency. The centrifugal force generated by wobbling motion will force the liquid in the metal tube out. The dynamic characteristics of the pump are studied. A prototype pump is fabricated by four piezoelectric tubes and a steel tube with an outer diameter of 1.0 mm, an inner diameter of 0.7 mm and a length of 80 mm. Experimental results show that the system can pump tap water at a flow rate of 7.7 ml/min under a backpressure of 2.0 kPa.

Piezoelectric actuators exhibit large hysteresis between the applied voltage and their displacement. A switched capacitor charge pump is proposed to reduce hysteresis and linearize the movement of piezoelectric actuators. By pumping the same amount of charges into the piezoelectric actuator quantitatively, the actuator will be forced to change its length with constant step. Compared with traditional voltage and charge driving, experimental results demonstrated that the piezoelectric stack driven by the charge pump had less hysteresis over a large frequency range, especially at ultralow frequencies. A hysteresis of less than 2.01% was achieved over a frequency range of 0.01-20 Hz using the charge pump driver.

This paper reports a piezoelectric device based on a cantilever with an extended auxiliary part that forms a right angle with the basic part. Theoretical analyses and experiments support that, by using such a device, uniform strain distribution in piezoelectric element surfaces can be obtained, and thus the piezoelectric materials can be used more efficiently. A piezoelectric element on a right-angle cantilever can generate a useful power twice that of a traditional cantilever under the same strain limitation.