scholarly journals Vibration Information Acquisition and Representation Control Strategy for Construction Vehicle Driver Seat

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Mingde Gong ◽  
Baoqiang Zhao ◽  
Xin Wang

Vibration information acquisition and representation control strategy in the experiment of construction of vehicle driver seat are investigated in this study. An improved adaptive algorithm of multisensor attitude data fusion is proposed. The nonlinear equations of vehicle attitude quaternions are constructed by using the test information of accelerometers and magnetometers. Then, a complementary filter is used to fuse the obtained attitude with gyroscope information to obtain attitude information during vehicle travel. Weight matrix and filter coefficients in the algorithm are adjusted with vehicle motions to ensure accuracy of attitude measurement under static, low-, and high-acceleration conditions. The vehicle vibration displacement information is reconstructed by the low-frequency attenuation integration method on the basis of attitude measurement to inhibit integral trend items and reduce vibration displacement reconstruction errors. The three-state controller is designed to control a six-degree-of-freedom hydraulic simulated vibration test bed, and the obtained vibration signal is used as an excitation signal to perform a vibration representation control test. Finally, results verify that the proposed method demonstrates favourable data fusion and representation accuracy.

2010 ◽  
Vol 450 ◽  
pp. 552-555
Author(s):  
Ping Wang ◽  
Kai Xue ◽  
Qiu Hong Li

GPS attitude tracking system on the ship is a servo mechanism which could be used for counteracting the effects of the ship’s pitch and roll. But the attitude measurement precision of ship is more important to the tracking precision of the servo mechanism. As one of the major error sources, the noises of GPS attitude measurement bring out the steady tracking error of the tracking servo mechanism. To reduce the steady error due to the noise, the threshold noise removing method of wavelet is used to eliminate the noise. And the better result with the meaning of standard deviation and the better visual effects could be gotten by using the method. The signals of the processed high frequency and the retained low frequency could be reconstructed with the original signals. Therefore, the signals after noise removing could be obtained. The threshold noise removing method of wavelet used to remove the noise of GPS attitude information in the paper is of great value in practice.


2013 ◽  
Vol 345 ◽  
pp. 64-67
Author(s):  
Jian Hua Zhao ◽  
Rui Bo Zhang ◽  
De Bin Zhu ◽  
Hong Bin Gao

Shock test of marine diesel engine is the important content for ship anti-shock research. Plentiful shock tests of equipments have been carried out abroad, but there is no detailed test methods of diesel engine. According to simulation results, 8-channel acceleration test points are determined. Because diesel engine is working, the measured shock acceleration is interfered by vibration signal. Orthogonal wavelet decomposition and wavelet noise reduction methods are used to separate shock component from test results. The seperated shock component consists of two parts. One is the low-frequency part caused by the shock from diesel foundation and then attenuation through the isolator, the other is the high-frequency part caused by the secondary shock of the retainer.


2021 ◽  
Author(s):  
Chenguang Wang ◽  
Chongtao Li ◽  
Kehan Zeng ◽  
Yiping Chen ◽  
Liang Xiao ◽  
...  

Author(s):  
Ying He ◽  
Muqin Tian ◽  
Jiancheng Song ◽  
Junling Feng

To solve the problem that it is difficult to identify the cutting rock wall hardness of the roadheader in coal mine, a recognition method of cutting rock wall hardness is proposed based on multi-source data fusion and optimized probabilistic neural network. In this method, all kinds of cutting signals (the vibration signal of cutting arm, the pressure signal of hydraulic cylinders and current signal of cutting motor) are analyzed by wavelet packet to extract the feature vector, and the multi feature signal sample database of rock cutting with different hardness is established. To solve the problems of uncertain spread and complex network structure of probabilistic neural network (PNN), a PNN optimization method based on differential evolution algorithm (DE) and QR decomposition was proposed, and the rock hardness was identified based on multi-source data fusion by optimizing PNN. Then, based on the ground test monitoring data of a heavy longitudinal roadheader, the method is applied to recognize the cutting rock hardness, and compared with other common pattern recognition methods. The experimental results show that the cutting rock hardness recognition based on multi-source data fusion and optimized PNN has higher recognition accuracy, and the overall recognition error is reduced to 6.8%. The recognition of random cutting rock hardness is highly close to the actual. The method provides theoretical basis and technical premise for realizing automatic and intelligent cutting of heading face.


Sensors ◽  
2019 ◽  
Vol 19 (14) ◽  
pp. 3125
Author(s):  
Zou ◽  
Chen ◽  
Liu

Considering the lack of precision in transforming measured micro-electro-mechanical system (MEMS) accelerometer output signals into elevation signals, this paper proposes a bridge dynamic displacement reconstruction method based on the combination of ensemble empirical mode decomposition (EEMD) and time domain integration, according to the vibration signal traits of a bridge. Through simulating bridge analog signals and verifying a vibration test bench, four bridge dynamic displacement monitoring methods were analyzed and compared. The proposed method can effectively eliminate the influence of low-frequency integral drift and high-frequency ambient noise on the integration process. Furthermore, this algorithm has better adaptability and robustness. The effectiveness of the method was verified by field experiments on highway elevated bridges.


2021 ◽  
Author(s):  
Arpan Chatterjee ◽  
Perry Y. Li

Abstract The Hybrid Hydraulic-Electric Architecture (HHEA) was proposed in recent years to increase system efficiency of high power mobile machines and to reap the benefits of electrification without the need for large electric machines. It uses a set of common pressure rails to provide the majority of power hydraulically and small electric motors to modulate that power for precise control. This paper presents the development of a Hardware-in-the-loop (HIL) test-bed for testing motion control strategies for the HHEA. Precise motion control is important for off-road vehicles whose utility requires the machine being dexterous and performing tasks exactly as commanded. Motion control for the HHEA is challenging due to its intrinsic use of discrete pressure rail switches to minimize system efficiency or to keep the system within the torque capabilities of the electric motor. The motion control strategy utilizes two different controllers: a nominal passivity based back-stepping controller used in between pressure rail switches and a transition controller used to handle the event of a pressure rail switch. In this paper, the performance of the nominal control under various nominal and rail switching scenarios is experimentally evaluated on the HIL testbed.


Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 1102 ◽  
Author(s):  
Hamidreza Heidari ◽  
Anton Rassõlkin ◽  
Toomas Vaimann ◽  
Ants Kallaste ◽  
Asghar Taheri ◽  
...  

In this paper, a new vector control strategy is proposed to reduce torque ripples and harmonic currents represented in switching table-based direct torque control (ST-DTC) of a six-phase induction motor (6PIM). For this purpose, a new set of inputs is provided for the switching table (ST). These inputs are based on the decoupled current components in the synchronous reference frame. Indeed, using both field-oriented control (FOC) and direct torque control (DTC) concepts, precise inputs are applied to the ST in order to achieve better steady-state torque response. By applying the duty cycle control strategy, the loss subspace components are eliminated through a suitable selection of virtual voltage vectors. Each virtual voltage vector is based on a combination of a large and a medium vector to make the average volt-seconds in loss subspace near to zero. Therefore, the proposed strategy not only notably reduces the torque ripples, but also suppresses the low frequency current harmonics, simultaneously. Simulation and experimental results clarify the high performance of the proposed scheme.


Sensors ◽  
2020 ◽  
Vol 20 (18) ◽  
pp. 5307
Author(s):  
Yeying Tao ◽  
Wei Jiang ◽  
Bin Han ◽  
Xiaoqing Li ◽  
Ying Luo ◽  
...  

A piecewise frequency control (PFC) strategy is proposed in this paper for coordinating vibration isolation and positioning of supporting systems under complex disturbance conditions, such as direct and external disturbances. This control strategy is applied in an active-passive parallel supporting system, where relative positioning feedback for positioning and absolute velocity feedback for active vibration isolation. The analysis of vibration and deformation transmissibility shows that vibration control increases low-frequency position error while positioning control amplifies high-frequency vibration amplitude. To overcome this contradiction across the whole control bandwidth, a pair of Fractional-Order Filters (FOFs) is adopted in the PFC system, which increases the flexibility in the PFC design by introducing fraction orders. The system stability analysis indicates that the FOFs can provide a better stability margin than the Integral-Order Filters (IOFs), so the control gains are increased to get a better performance on the AVI and positioning. The PFC based on FOFs can suppress the peak amplitude at the natural frequency which cannot be avoided when using the IOFs. The constrained nonlinear multivariable function is formed by the required performance and the stability of the system, then the controller parameters are optimized effectively. Lastly, the effectiveness of the proposed method is verified by experiments.


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