Research on Servo Tracking Control of Ultra-precision Machine Tools Based on Limited Bandwidth Expectation Model

Wang Lisong, Zhang Feihu, Su Baoku, Dong Shen Abstract In order to realize high-speed and high-precision tracking of ultra-precision machine tools, it is proposed to use the future information for all the movements in the design of the stagnation system. The controller is applied in the actual system, and the maximum steady-state tracking error of the system is less than 25 when the sinusoidal signal is tracked. Dr. Lisong researches ultra-precision machine tools is an important basic equipment for realizing advanced manufacturing technology. With the development of the economy, Not only the shape of the machined workpiece becomes more complicated, but also puts higher requirements on the productivity and accuracy of the machine tool. The ultra-precision machine is the machine that determines the machine, the precision of the machining and the speed factor. The system deviates from the current and past time to design the controller, and completely ignores the addition of the parts. The predicted long-distance signal is used. The method of the calibration system after correction has a large phase lag in the frequency band, and the servo system The tracking error is very sensitive to the phase lag, so large tracking errors will occur during high-speed machining, and the quality of the part surface will deteriorate. High-speed and high-precision control method for ultra-precision machine tools with limited bandwidth expectation model.

Inverse system design method and speech bandwidth expectation model 1.1 Inverse system design using future information The design of the servo system is to pursue the output reproducibility of the input, that is, there is a constant person, so that the output 10 loses 0 and satisfies = ruler and when Especially =1, at this time, the system realizes the full recurrence of the input to the input hypothesis 02 is a linear time-invariant discrete system, and 2 is progressively stable, 62 is the pre-compensator, then the output and transmission of the transfer fund project This natural science 7 gold ribs Shenshan 5,351 Ming number can be small (1) (4), that is (4), can achieve the system's output (1) on the input and (1) full reproduction can thus be set up the control system. The standard is calculated as 4 pre-compensator, the transfer function of the zero-phase lag is assumed to be 0, and 2 can be a polynomial containing all the zeros in the bit circle. The polynomial of all zeros on the unit circle and outside the unit circle is considered to be + pair. The effect of zero elimination point 6 is the same. According to the inverse system design idea of ​​zero-pole cancellation, 2 can be taken as 3 when there is no unstable zero point 621 in 2, and the inverse system design is adopted. If 6 contains the unit circle and the unit circle When the zero point is outside, the compensation of the formula 3 is used to obtain the sampling period, which is taken as 1 in this paper! It is easy to verify that Equation 4 has a constant phase difference between input and output in all frequency bands, and 1.7 tends to zero in the large frequency band Gz1 so force pre-compensation, even if. When the zero-point is not paid, the output can be fully reproduced in a large frequency range. The zero-sum lag in all frequency bands needs to utilize the future hole, information, for the ultra-precision machine tool due to its processing path in advance. It is known that in the future, information can be obtained. Therefore, this method of designing the base system is feasible. It is feasible to control the system of the thousand super-precision machine tool. 1.2 The limited bandwidth zero-phase lag expectation model uses the inverse system design of future information. The transfer function between the output and the input of the system is approximately 1 in a wide bandwidth. However, in practical applications, the bandwidth of the signal has a limit, so that the amplitude difference and phase between the input and output of the system are satisfied within a given signal bandwidth. The difference is less than the predetermined value. For the ultra-precision machine tool servo system, due to the limitation of the mechanical structure of the machine tool, there is a high-frequency oscillation mode in the system. If the system bandwidth is wide, the oscillation frequency is within the system bandwidth, which will cause the system to resonate. It is more meaningful to design a desired closed-loop frequency characteristic for a given bandwidth within the required frequency band. The ratio of the input to the output is 1. The other bands are 0; the phase lag is zero in all bands. This paper constructs a finite bandwidth zero-phase lag model that requires future information. Its mathematical formula is a corpse-type damper for the ring and current loop. Since the current loop time constant is small enough, it is simplified into a proportional link, and the dynamic torque model of the servo system of the toilet position is 3, the optical torque. It is mainly by. The torque fluctuation of the friction torque and the motor's duty causes the torque constant 1 to be 16.17. The speed regulator proportional coefficient 1 is the ratio of the 32 speed measuring machine, which is 0.796. 1. The ball screw transmission coefficient is 0.8131 and is input. No. 1 is the work pull position output. The rice sample cycle 7 is 3 in order to obtain the measured model of the system, and the frequency method is used to enter and identify the system. The open-loop transfer function of the servo system is identified so that the open-loop transfer function of the servo system can be obtained. During the frequency identification process, the system is found to have oscillations at 42 out 65 and 83 out, respectively. These oscillation modes are used as the system. In the unmodeled dynamic characteristic processing, it can be seen that the closed-loop frequency characteristic with limited bandwidth can obtain a resonance peak close to 10 000 and 13 in the desired bandwidth by selecting an appropriate value, which is due to the 2-plane spatial frequency. The composition of the 2 ultra-compacting machine feeding system and its dynamic model caused by the periodic characteristics of the characteristics The servo feed system of the ultra-precision machine tool realizes the position servo feed by the AC servo motor + ball screw. ! 1 Dual-frequency laser household instrument realizes position detection, and adopts air static pressure guide rail and air floating work table to reduce the influence of friction force in the transmission process. The system structure adopts a double closed-loop speed regulation structure of the inner loop of the outer loop of the current loop 4 for the AC servo drive unit of Muwen. The design of the speed 3 controller uses the inverse system design method of the future information, and the system is required. 2 is the progressive stability system. Therefore, the feedback controller is used to use the feedback controller to rotate the object, and then the 2 and the hole are stable. =. On this basis, the pre-compensator is designed. This paper adopts the controller with feedback + feedforward compensation equivalent to this structure. The design of the feedback controller 02 is mainly to ensure the system is used to improve the dynamic performance of the system. And after adding 2 and 2, it is necessary to ensure that the corrected system has a finite bandwidth of zero. 1. Feedback control 2 feedback + feedforward control feedback and feedforward compensation finder experimental results from which to see. The system only adds a feedback controller to track the sinusoidal signal.

It has a large sinusoidal tracking error, and its frequency is the frequency of the tracked signal. When the feedforward compensation is added, the tracking error of the system is greatly reduced, which is less than ±25 continent. It can be seen that this is composed of feedback + feedforward compensation. A controller with a limited bandwidth expectation model is effective for tracking performance of the modified system. The sinusoidal error of curve 2 in 5 is the fluctuation torque of the motor that is proportional to the rotational speed. If you want to improve the tracking error, only the servo stiffness of the feedback system or the interference feedforward compensation 5 conclusion point is proposed. A zero-phase lag expectation model with a predetermined bandwidth can be proposed. The amplitude characteristic of the model in the required frequency band is similar in other frequency bands. Zero, the phase lag is zero in all frequency bands and the feedback + feedforward control structure is used to implement the ideal model.

The feedback controller takes the form of proportional + integral. Its design guarantees the stability of the system and good interference suppression. Based on the feedback controller, the feedforward compensation controller can be derived from the finite bandwidth ideal model. In the process of derivation, the system with reversible zero point is considered. Finally, the controller should be used to verify the effectiveness of the controller designed in this paper. The feedback and time-feed compensation controller will be digitally displayed. It is applied to the servo system of type 1 ultra-precision machine tool. The machine tool adopts the United States, Shihan Company 0050 into the AC torque servo motor and the Japanese 208 Precision Dual-frequency laser meter. The resolution of the detection resolution 50 converter is the tracking error of the system whose tracking amplitude frequency is 81 chord curve. The curve 1 is the experimental result of adding only the feedback controller, and the curve 2 is the desired closed-loop frequency of adding the phase lag at the same time. Characteristic 2, Form 3.1 Feedback Controller Design Due to the short sampling period in this paper, the phase lag in the digital to analog conversion process can be neglected. Therefore, the simulation method is used to design the feedback controller.

Wood system is a type system. The design of this kind of control system usually comes down to how to design the system into a wide bandwidth and high stiffness servo system to ensure the system's faster response speed and strong anti-interference ability. 4 In this paper, the feedback controller 1 adopts the magic 1+ In the form of 1, because of the pure integral part of the system, the static servo stiffness of the system is infinite, so the system can effectively suppress the step disturbance on the motor shaft, and the better damping characteristics of the system can be adjusted by the parameter factory. Obtaining the compromise between the response speed noise error and the unmodeled dynamic characteristics of the system, this paper designs the bandwidth of the system as the final method to determine the proposed controller to use bilinear transformation. Yu is. The design of the digital controller Qiu Wei 3.2 feedforward controller is obtained by 4 and can be added to the system phase lag after 2 and 2. The expected closed-loop frequency characteristic ratio of 17 yields a feedforward controller that is only required to satisfy Equation 10.

It is possible to obtain a finite bandwidth zero-phase lag expectation model 2, which needs to be calculated for the desired appearance. (4) It can be seen from the equation that 62 has a zero point on the unit circle, and directly finds the inverse system design method for the zero-pole cancellation of the stable defect. An approximate stable inverse system of 62 is obtained, which is phantom to verify 1 and 6, so that the amplitude-frequency characteristic of the product can be approximated to a constant zero frequency characteristic in a large frequency band.

Then, the 2 in the middle of the substitution formula is similar to the one with the stagnation of the stagnation of the factory. The 2-step advance information is used in the actual application. Therefore, the 0 hook in the actual application needs to know the +2 step advance information of the future path. Taking 8 Bionic Active Component Piezoelectric Transducer 宄 设 Du Liang Liang Jianzhong Zhang Yun Chen Zichen Coupling Interactive System proposes how to establish a theoretical model of piezoelectric intelligent structure from multiple angles, and discusses the pressure of various parameters of piezoelectric coupled electromechanical system The influence of the energy conversion efficiency of the electric transducer, the establishment of the electromechanical coupling model of the piezoelectric intelligent structure helps to explain the physical essence of the bionic active component, and designs a smart structure with higher performance and higher efficiency.

Dr. Du Jianliang is a key component of the intelligent bionic structure. It integrates the sensor and the actuator into the body. It has the dual functions of structural bearing and actuation sensing in the structure. The active components are flexible, intelligent and efficient. The adaptability of the sexual environment is strong; the ideal active component and the controller work together to minimize the energy required by the active component and obtain the ideal dynamic response, so that the system can obtain better controllability and observability. According to the dynamic response and control requirements of the structure, the component can adaptively change the dynamic performance of the structure and truly realize the structural control body. It is the research focus of the current biomimetic structure. The positive and negative piezoelectric effects of the piezoelectric material are both strong and linear. Wide range of frequency response, in the bionic active component, can be used as a sensor or as an actuator.

The piezoelectric effect of the piezoelectric element determines the sensing and actuation characteristics of the active component, which is the essential factor affecting the efficacy of the biomimetic structure. Therefore, it is the key release date of the active component research. The 19990826 fund project National Natural Science Foundation funded project 5890501 In the actual system, the experimental results show that the control method combined with feedback control and feedforward compensation based on future path information can effectively improve the tracking characteristics of the system, and has greater practical value in engineering applications in order to better explain bionics. The piezoelectric effect in the active component is proposed as a unified model of the coupled electromechanical system. The model points out that the piezoelectric element contains a piezoelectric transducer, which establishes the mathematical model of the card-electric converter from multiple angles in the conversion energy of mechanical energy and electrical energy, and studies the effects of each and several pairs of system performance. The research and development and optimization design of active components is crucial. 1 Theoretical modeling of piezoelectric transformers. Accurate mechanical model analysis is the basis of effective system identification and control. The theoretical modeling of piezoelectric-type bionic structures is mainly There are three basic methods: dynamic finite element method impedance modeling analysis and static method piezoelectric transformer model to help explain the physical essence of its electromechanical coupling interaction, design better performance dynamic finite element method with piezoelectric Among the characteristics of the material, the mechanical behavior of the material and the electricity hall are not independent, but connected by phase 2; electric shock Wang Guangxiong. Control system design. Beijing Aerospace Publishing House, 1992140168 edited Zhou Youqi 150001 Ph.D. in the Department of Control Engineering, and published 8 papers. Zhang Feihu, male, born in 1964. Harbin Institute of Technology, College of Mechanical and Electrical Engineering, arrived in Su Baoku, male, born in 1941. Professor of the Department of Control Engineering, Harbin Institute of Technology, Ph.D.

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Applications
SZG rotary Double Cone Vacuum Dryer is designed for drying and mixing of powdery and granular materials in the pharmaceutical, food and chemical industries, for example:
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5. Materials requiring low-content residual volatile matter

Features
Our rotary vacuum dryer includes three types of heat source, including steam, hot water and heat transfer oil.
This simple-structure drying equipment is convenient to clean and easy to operate.
Material in the dryer can also be rotated due to the rotation of the machine, which helps minimize material water content (≤0.5%).
Material doesn't stick to the walls of the container, resulting in high heat transfer coefficient and high drying rate.


Technical Specifications of Rotary Double Cone Vacuum Dryer

Model

Volume(L)

Heating area(m2)

Power(kw)

Rotation speed(rpm)

Turning height(mm)

Tube design pressure(mpa)

Interlayer design pressure(mpa)

Weight(kg)

SZG-100

100

1.16

0.75

6

1810

-0.09~0.096

≤0.3

800

SZG-200

200

1.5

1.1

6

1910

-0.09~0.096

≤0.3

1000

SZG-350

350

2

1.5

6

2090

-0.09~0.096

≤0.3

1100

SZG-500

500

2..63

1.5

6

2195

-0.09~0.096

≤0.3

1200

SZG-750

750

3.5

2.2

6

2500

-0.09~0.096

≤0.3

1480

SZG-1000

1000

4.61

3

6

2665

-0.09~0.096

≤0.3

2800

SZG-1500

1500

5.58

3

6

2915

-0.09~0.096

≤0.3

3300

SZG-2000

2000

7.5

4

6

3055

-0.09~0.096

≤0.3

3580

SZG-3000

3000

9.6

5.5

4

3330

-0.09~0.096

≤0.3

5950

SZG-4500

5000

13.8

7.5

4

4210

-0.09~0.096

≤0.3

9960

 

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