Design of high precision mechatronic-hydraulic leveling system for vehicle-mounted radar

In order to improve the control performance of vehicle-mounted radar, a high precision leveling control system is designed through mechatronic-hydraulic integration technology. A leveling method combining angle error leveling method and height error leveling method is designed, and inclinometers are set in the front and rear of the vehicle body platform to effectively eliminate the virtual outrigger phenomenon in the leveling process. The mathematical model of hydraulic system is developed, the fuzzy PID control method is introduced, and the four-point support hydraulic leveling control system is developed by using STM32 microcontroller as the control core. The field test proves that the control system has good control performance, high leveling accuracy, short time, and meets the control requirements of the radar vehicle.

Wire Tension Coordination Control of Electro-Hydraulic Servo Driven Double-Rope Winding Hoisting Systems Using a Hybrid Controller Combining the Flatness-Based Control and a Disturbance Observer

When the double-rope winding hoisting system (DWHS) is in operation, tensions of two wire ropes of the DWHS will not be symmetrical because of some factors such as different manufacturing deviation between the twin winding drum and two wire ropes, different winding groove depths, the winding asynchronism of two wire ropes, and elastic modulus difference of two wire ropes and so on. Therefore, an electro-hydraulic servo system (EHSS) is employed to actively control two wire ropes tensions to guarantee operation security of the DWHS. Dynamic models of the hoisting system and the EHSS are introduced, of which dynamic model of the DWHS is expressed with state representation. The flatness-based controller (FBC) is designed for the hoisting system. A disturbance observer is utilized to deal with the external disturbance and unmodeled characteristics of the EHSS. Hence, a disturbance observer based integral backstepping controller (DO-BIBC) is designed for the EHSS. The stability of the overall control system is proved by de-fining an overall Lyapunov function. To investigate the property of the proposed controller, an experimental setup of the DWHS is established. As well, comparative experimental results indicate that the proposed controller exhibits a better performance on leveling control of the conveyance and tension coordination control on the two wire ropes than a conventional PI controller.

Four-point dynamic leveling method for drilling platform application

Purpose It is essential to level the drilling platform across which a drilling robot travels in a slant underground coal mine tunnel to ensure smooth operation of the drill rod. However, existing leveling methods do not provide dynamic performance under the drilling conditions of the underground coal mine. A four-point dynamic leveling algorithm is presented in this paper based on the platform attitude and support rod displacement (DLAAD). An experimental drilling robot demonstrates its dynamic leveling capability and ability to ensure smooth drill rod operations. Design/methodology/approach The attitude coordinate of the drilling robot is established according to its structure. A six-axis combined sensor is adopted to detect the platform attitude, thus revealing the three-axis Euler angles. The support rod displacement values are continuously detected by laser displacement sensors to obtain the displacement increment of each support rod as needed. The drilling robot is leveled according to the current support rod displacement and three-dimensional (3 D) attitude detected by the six-axis combined sensor dynamically. Findings Experimental results indicate that the DLAAD algorithm is correct and effectively levels the drilling platform dynamically. It can thus provide essential support in resolving drill rod sticking problems during actual underground coal mine drilling operations. Practical implications The DLAAD algorithm supports smooth drill rod operations in underground coal mines, which greatly enhances safety, reduces power consumption, and minimizes cost. The approach proposed here thus represents considerable benefits in terms of coal mine production and shows notable potential for application in similar fields. Originality/value The novel DLAAD algorithm and leveling control method are the key contributions of this work, they provide dynamical 3 D leveling and help to resolve drill rod sticking problems.

Angle and Force Hybrid Control Method for Electrohydraulic Leveling System with Independent Metering

The electrohydraulic leveling system of the hydraulic press can realize automatic leveling control function. In order to eliminate the eccentric load force accurately, an electrohydraulic leveling system with independent metering is designed. Quasi-static behavior analysis of the leveling cylinders output forces performance is applied to the electrohydraulic leveling system with independent metering. The angle and force hybrid control method is proposed, and then the AMESim/Simulink cosimulation model is built. The HSIC controller and PID controller are used in the simulation, respectively. Simulation results show that both of the leveling angle control and leveling cylinders output forces control can be realized, simultaneously, and the HSIC controller has higher rapidity and smaller overshoot than the PID controller.

Leveling Control of Vehicle Load-Bearing Platform Based on Multisensor Fusion

In the large-scale transportation, the leveling of the transport vehicle loading platform will determine the safety of the transportation. Therefore, the research on the leveling of the transport vehicle loading platform with hydraulic suspension is carried out. The hydraulic suspension systems are simplified as four-point support. Based on the multisensor data collected by the pressure sensors of the suspension hydraulic cylinders and the double axis inclination sensor of the load-bearing platform, the leveling control system of the four-point load-bearing platform is designed according to the principle of the highest point chasing. In order to verify the precision of the leveling method, the leveling of the control system is simulated by using the software AMESim and MATLAB, and the PID controller is added. The results show that the leveling precision and velocity of this method fully meet the leveling requirements of the transport vehicle. On the basis, the leveling control system for the 100 ton transport vehicle is designed. The double axis inclination sensor is used to monitor the tilt angle of the loading platform in real time. The controller can make the suspension hydraulic cylinders act accordingly according to the four height differences to keep the loading platform level. Finally, the leveling experiment of the transport vehicle is carried out, and the lifting experiment is carried out under the condition of no load to full load. It is concluded that the displacement of the four points of the load-bearing platform of the transport vehicle is basically the same. The leveling control system can control the inclination angle of the platform within 0.25 degrees, and the leveling time is less than 1 second. The leveling process has higher precision and shorter time than other methods, which can provide reference for the leveling design of similar platforms.

Research on Electromechanical Four-Point Leveling Control System Based on MPC

<p>Multi-supporting leveling platform was wildly applied in areas of normal or military industry. To complete some frocking targets, it usually requires good performance of levelness and short time adjustment. It is very meaningful to enhance the automatic level of leveling platform by mining adaptive controlling algorithm which satisfied the levelling error and used shorter time. In this paper, four-point supporting electromechanical leveling system was set as the object to study. By analyzing the leveling characteristic of the system, appropriate leveling strategies were put forward. The simulation result of the system, whose model was built based on MPC, show that this way achieves good auto leveling performance.</p>

THE RESEARCH LAYOUT OF IMAGE CONTROL POINTS FOR 1:1000 B LEVEL DIGITAL ELEVATION MODEL PRODUCTION BASED ON UAV IN PLAIN AREA

With the advent of the era of big data, traditional measurement techniques have been difficult to meet the information extraction required by contemporary measurement products, and light UAV （Unmanned Aerial Vehicles）was used to mapping is one of the development trends of aerial photogrammetry in China. When data is processed on aerial photography, the control points in the measurement area directly affect the accuracy of the later mapping results as the basis of mathematical calculation. However, the traditional aerial photogrammetry lays out the number of image control points according to a wide range of industry specifications, For example, lay Leveling control point at four corners + a row of elevation control points is lay at both ends of the area and lay Leveling control point at four corners + two vertical framed air routes at both ends of the zone (Zhang, J. Q., 2009),there are no specific method for the number of image control points to achieve a certain scale accuracy. As a result, there are too many or too few image control points in different topography and different scales. Measured by the error, image point density and reasonable layout of the data acquisition of the Trimble UX5 UAV, The causes of the errors are analyzed, and the precise data are obtained by comparing the experiments. Based on this, the relationship between changing the density of image control points and reasonable location is analyzed through the typical plain survey area of 0.718 km2. Designing four layout schemes of Image control points, taking the national standard as the standard, four groups of data are studied by comparing and analyzing GPS acquisition data with photogrammetry mapping data of Wuhan VISIONEK INC MapMatrix software. Through experimental analysis, the results show that the experimental data show that the light UAV can satisfy the production of 1:1000 B level digital elevation model in plain area when the image resolution is 350 dpi, the line height is controlled at 180 ± 10 m and the density of image control point is more than 9/km2. At the same time, this image control point layout method is used reasonably can reduce the workload of the field, improve work efficiency, and also help to speed up the calculation of huge amount of aerial survey data so as to produce high-precision digital products.