Scheme of electromechanical automatic leveling system for vehicle-mounted radar
Modern warfare has increasingly higher requirements on radar maneuverability. Especially, mobile land carriers such as vehicle-mounted radar antennas, launchers and other equipment, after reaching a predetermined location, require rapid and accurate horizontal datums. Manual manual leveling of the vehicle-mounted platform has been difficult to meet the military's requirements for rapid erection, rapid withdrawal of radar, and high-precision leveling of the platform. Compared with manual leveling, electromechanical automatic leveling has the characteristics of short leveling time, high leveling accuracy and high reliability. This design is an electromechanical four-point support automatic leveling follow-up control system that uses a single-chip computer and CPLD as the control core, and a servo controller and servo motor as the execution unit. . Its advantages are short leveling time (less than 3 minutes), high leveling accuracy (less than 3 '), high reliability, and ability to work in harsh environments.
System composition
Leveling principle
The leveling method usually has a 3-point or 4-point type, and in particular, a multi-point type such as a 6-leg or more-leg platform. According to the actual application situation, this system adopts 4-point leveling method. The X-axis and Y-axis of the working platform supported by four points are the two axes perpendicular to each other on the working platform surface according to the installation position of the horizontal sensor. The leveling principle is shown in Figure 1.
After the supporting legs of the working platform touch the ground, the control system starts to level. Through the detection signal of the level sensor, the highest point of the working platform can be found. Place the horizontal sensor on the working platform in the direction as shown in Figure 1. The sensor output contains X and Y axis signals, which are digital signals in a linear relationship with the horizontal error (angle). When X> 0, Y <0, the leg A is the highest point; when X <0, Y <0, the leg B is the highest point; when X <0, Y> 0, the leg C is the highest point; X > 0, Y> 0, the leg D is the highest point.
Assuming that the leg A is the highest point after the leg is on the ground (other legs are similar to the highest point), according to the signal of the level sensor, the X-axis and Y-axis directions can be adjusted separately. If the X-axis adjustment is performed first, the process is as follows: the legs A and D do not move, and legs B and C rise simultaneously by a certain displacement, that is, the working platform rotates around legs A and D as the axis, and legs B and C rise simultaneously. The rising value is determined by the control system according to the X-axis feedback value of the level sensor until the X-axis is in a horizontal state. The Y axis adjustment is similar to the X axis. If the X-axis and Y-axis of the worktable are adjusted to a horizontal state, it can be considered that the worktable is already in a horizontal state. The horizontal error of 4-point leveling is q2 = q12 + q22, and q1 and q2 are the angle accuracy of the level sensor. If the control accuracy of both sensors is δ, then the horizontal error.
One of the main problems faced by the 4-point and multi-point leveling design is the virtual leg phenomenon, that is, one leg is under a small force or is suspended, which is not allowed during the leveling process. When the load of the platform is uniform, the stress of the four support points should be uniform. The processing method designed by this system is to carry out a rough leveling (setting a coarse precision) after supporting the platform, the purpose is to make the force of the four support points closer. Then, perform leveling according to the leveling accuracy set by the system. In this way, the force of one leg (virtual leg) will not appear in the adjustment process, thereby effectively preventing the phenomenon of the virtual leg.
Hardware composition
The hardware composition of the automatic leveling system is shown in Figure 2. The system is mainly composed of control part, level sensor, pressure sensor, servo controller, servo motor and servo electric cylinder.
The horizontal sensor (X and Y directions) measures the inclination of the vehicle platform, and sends the inclination data in the X and Y directions to the control part through the RS232 serial port. The baud rate is 9600 bit / s. The level sensor used in this system has a measurement accuracy (zero position) of 0 ± 20 "and a resolution of ≤4", which fully meets the requirements of platform tilt angle measurement and leveling.
The pressure sensor is used to measure the pressure supported by the four supporting feet. The measurement range is 0 to 9000 kg. The pressure data is sent to the control part through the RS232 serial port. The baud rate is 9600 bit / s.
The control part is mainly composed of control board, servo driver and drive interface unit. The control board is the core of the control part, which is mainly composed of a single chip microcomputer, CPLD, multi-channel DAC, multi-serial port expansion circuit, RS232 level conversion circuit, watchdog circuit, etc. When the operator sends the control command to the control board through the button, the CPU reads the data sent by the level sensor and the pressure sensor to judge and form a control strategy, generates a control signal and sends it to the servo controller by the DAC, and then controls the drive interface circuit to drive a certain The servo motor runs all the way until it is leveled. For the safety of operation, the entire leveling operation process is indicated by sound and light. The control part displays the inclination and pressure data in real time, which is convenient for the operator to monitor.
The leveling process of this vehicle radar platform is completed in two stages. The first stage is the erection stage, that is, after the vehicle-mounted radar reaches the position, the four supporting legs are controlled to land on the ground for landing detection. After the system is powered on, the operator only needs to press the "erection" button on the operation panel to control the system to drive the servo motor to lift the support legs, and at the same time detect whether each support leg touches the ground, and stop the lifting action of a certain support leg when it touches the ground. When all four supporting legs touch the ground, the landing detection ends. The second stage is the leveling stage. The operator presses the "leveling" button on the operation panel, and the single-chip microcomputer reads the inclination data of the current vehicle platform sent by the level sensor and the force data of each support leg sent by the pressure sensor, and according to the inclination data and pressure data, according to the control The strategy drives the corresponding motor to raise the corresponding supporting leg until the inclination of the vehicle reaches the requirements of the radar system.
System program workflow
The work flow block diagram of this system is shown in Figure 3.
Conclusion
The radar automatic leveling system is an important part of the vehicle-mounted radar, and plays a decisive role in improving the measurement performance of the radar, such as the measurement accuracy of the target angle and the speed of the whole frame installation and withdrawal. This system adopts single chip microcomputer and CPLD control, and uses AC servo control, which greatly improves the horizontal accuracy and adjustment time of the platform when the radar antenna is installed, and has the characteristics of high reliability and good maintainability.
8 Inch Tablet
Today let`s talk about 8 inch tablet with android os or windows os. There are many 8 inch tablets on sale you can see at this store. 8 inch Android Tablet is absolutely the No. 1 choice if you are searching a student online learning project. 8 inch windows tablet is more welcome when clients are looking tablet for business application. The most welcome parameters level is 2 32Gb with 4GB lite, 4000mAh, android 11 only around 60usd, price will be much competitive if can take more than 1000pcs. 7 Inch Tablet wifi only, android tablet 10 inch, Amazon 8 inch tablet is also alternative here. Except tablet, Education Laptop, Gaming Laptop, 1650 graphics card laptop, Mini PC and All In One PC are the other important series.
Therefore, you just need to share the configuration, application scenarios, quantity, delivery time, and other special requirements, then will try our best to support you.
Any other thing in China we can do, you can also feel free to contact us.
You will find that cooperating with us is the best choice, not only save time and energy, but also save much cost.
8 Inch Tablet,8 Inch Android Tablet,Amazon 8 Inch Tablet,8 Inch Tablets On Sale,8 Inch Windows Tablet
Henan Shuyi Electronics Co., Ltd. , https://www.hnsylabtop.com