TWI257537B - Leveling apparatus and control module thereof - Google Patents

Abstract

A leveling apparatus having a tilt sensor, a processor, and an actuator is provided. The tilt sensor detects a tilt angle and accordingly outputs a sensor signal to the processor. The processor further includes a reference unit providing a reference signal and a PID control unit performing a PID operation to output a control signal based on the difference between the sensor signal and the reference signal. The actuator adjusts the tilt angle based on the control signal.

Description

1257537

I. TECHNICAL FIELD OF THE INVENTION The present invention relates to a level adjusting device. The present invention is more related to a level adjusting device using a PID control method. First, [previous technology]

• Proportiona L integral-derivative control (referred to as PID control) has a wide range of applications in engineering applications. The PID control state is simple to set up, stable and reliable, and easy to adjust. Especially when it is impossible to grasp the structure and coefficient of the controlled object, or it is difficult to construct an accurate mathematical model, the design technique under the control theory is difficult to use. Therefore, the structure and coefficient of the controller of the system must be determined by experience and on-site debugging. PID control technology is most suitable. When it is impossible to master

When a system and a controlled object are used, or when the coefficient of the system cannot be obtained by effective measurement means, the p丨D control technique can be used. X

Wheel PID control consists of three parts: proportional (P), integral (1), and differential (1). There are also PI and PD controllers. The PID controller calculates the control amount by using the proportional integral differential according to the error of the system. The relationship between the controller output and the control crying (error) is expressed in the following equation in the time domain; u(t) represents the controller. The output, e(t) represents the controller input (error ^ KP is the proportional coefficient, K! is the integral coefficient, and the heart is the differential coefficient:

1257537 V. Description of invention (2)

u(t) = Kpe(t) + Γ J e(t)dt+KD Proportional control (P control) is one of the simplest control methods. Indicates that the output of the controller is proportional to the input error signal. When there is only a proportional control day, the system output has a steady state error (S t e a d y - s t a t e e r r 〇 r ). In integral control (I control), the output of the controller is proportional to the integral of the input (error) signal. For an automatic control system, if there is a steady state error after entering the steady state, the control system has a steady state error or a system with Steady-state Error. In order to eliminate the steady-state error, the “integral term” must be introduced in the controller. The integral term performs an integral operation on the error with respect to time. As time increases, the integral term increases. Thus, even if the error is small, the integral term It will also increase with time. 'It pushes the output of the controller to increase the steady-state error further until it equals zero. Therefore, the proportional integral (pl) controller can make the system have no steady state after entering the steady state. In the differential control, the output of the controller is proportional to the micro-input of the input (error) signal, that is, the rate of change of the decision. The automatic control system may oscillate or even lose in the process of overcoming the mis-presentation. The reason is because there are components with large inertia and components with hysteresis (1 W), so that slaves overcome the effect of error's change always lags behind the error. The solution is to overcome the effect of error. Change needs, advance,, that is, when the error is close to zero, the effect of overcoming the error should be zero. That is, in control

1257537 V. Description of invention (3) = The introduction of the "proportional" item is often not enough, the proportion of the proportional item is the magnitude of the difference, and the target is to increase the "differential item", "quote" It is possible to predict the trend of the error change, so that the two devices with proportional differential can make the control effect of overcoming the error equal to the zero-working value in advance, thereby avoiding the overshoot of the controlled amount. Therefore, the dynamics of the larger 2 process are Characteristics. Control... Wenshan system has many methods for adjusting the coefficient in the controller. The general class is: the theoretical calculation adjustment method. It is mainly based on the mathematical model of the system, using some methods in the control theory. After theoretical calculations, it is determined that:: ίί. The method of calculating not only calculates the complexity but also relies too much on the system: the actual data may not be directly used, and must be adjusted and modified through privately. 35. It relies mainly on engineering experience, directly in the control system = 1 single, easy to master 'quite practical, (d) in engineering; the engineering adjustment method of the coefficient of the 匕p ID controller, the main common point Cloth by experiment, and then adjusted in accordance with known engineering experience coefficient sumac. But no matter which of several ten == obtained by the method employed, the final adjustments need to be in the actual operation with two cover End "

1257537 V. INSTRUCTIONS (4) In the flat two-shot adjustment device, the fast and accurate water Zhengtong* is the ultimate goal of horizontal adjustment, but with the design of the mechanism, the limit: the reaction speed of the horizontal sensing device The processing of horizontal signals and other factors, there are still deficiencies in achieving a fast and accurate goal. The control method has the above-mentioned characteristics. Therefore, if it is possible to have a level adjusting device using PID control, it can not only overcome the above disadvantages, but also has a better advantage in the industrial and private application. 3. SUMMARY OF THE INVENTION The main object of the present invention is to provide a level adjusting device using piD control. Another object of this month is to provide a leveling device that uses a digital PID control unit to provide pulsed current for precise control of the DC motor.

It is still another object of the present invention to provide a level adjusting device using a P I D control method in which coefficients in a piD operation can be easily adjusted. A horizontal adjustment device is provided, comprising a tilt sensor, a processing unit, and a Xiao-actuator. The tilt sensor is configured to sense a tilt angle to send a sensing signal to the processing unit. The processing unit further includes a reference unit το and a PID control unit. This reference | yuan for the supply - reference signal;

1257537

The PID control unit performs a PID operation based on the difference between the sensing signal and the reference signal to output a control signal. The actuator adjusts the tilt angle based on this control signal. The present invention further provides a control module for a level adjustment device, which is provided in a level adjustment device, the level adjustment device comprising a tilt sensor and a DC motor. The tilt sensor senses an angle of inclination to output a sense signal to the control module. The control module further includes a horizontal reference unit and a digital PID control unit. The horizontal reference unit provides a horizontal reference signal; the digital PID control unit performs a PID operation based on the difference between the sensing signal and the horizontal reference signal to output a control signal. The actuator adjusts the tilt angle based on the control signal. The present invention provides an improved level adjustment device and a control module for a horizontal adjustment device that reduces the time required to reach an equilibrium state. In addition, the digital P ID control unit controls the current through the pulse current, which increases the control accuracy and avoids the expensive cost of the stepper motor. Fourth Embodiment [Embodiment] FIG. 1 is a horizontal adjustment device 10 according to a consistent embodiment of the present invention, including a tilt sensor 12, a processing unit 14, and an actuator 16. The dip sense sensor 1 2 is used to sense a dip angle to rotate at least one sense signal. In addition, the present invention can be combined with a laser source 1 8 ' for emitting a laser beam, using this

1257537 V. Description of invention (6) The beam of the field can be scanned out of a plane. It is also within the scope of the present invention to utilize other sources (e.g., an infrared beam) to scan or otherwise define a plane in conjunction with the present invention. 2a is a functional block diagram of the level adjusting device j 所示 according to an embodiment of the present invention. The processing unit 14 includes a reference unit 142 and a ρΐ[) control (Pr〇P〇rtl〇nal-integrab) control unit 1^4' performs a piD operation according to the difference between the sensing signal 14ι and the reference signal 143. ^ Output a control signal 145. The actuator 16 adjusts the tilt angle 13 based on the control signal 145. The tilt sensor 12 is a two-way tilt sensor that detects an angle of inclination in the \ direction and the gamma direction, respectively. In another embodiment, the tilt sensor is a one-way tilt sensor that can detect an angle of inclination in a predetermined direction. The invention is preferably implemented by using a bidirectional tilt sensor, but to simplify The following will use the tilt angle detected by the tilt sensor 丨2 in the 乂 direction. The child's dip sensor 1 2 converts the tilt angle 13 measured in the X direction into a sense signal 141 and outputs it to the processing unit 14. The voltage value of the test signal 14] [corresponds to the tilt angle 丨3, that is, the greater the detected tilt angle 丨3, the greater the voltage value of the sense signal 141. In this embodiment, this voltage ranges from 〇 to 2.5 V. In addition, in order to output the sensing signal 141, the tilt sensor 12 may also include a signal processing device (not shown) such as an amplifier or a filter. The reference unit 142 outputs a reference signal 143 to the PID control unit 144 according to a preset by the user. In this embodiment, this reference message

1257537 V. Invention Description (7) No. 143 is a horizontal reference signal, that is, the voltage f ' in the reference signal is equivalent to when the level adjusting device reaches a level, the tilt sensor 12 rotates and senses The voltage value in signal 141. It is worth mentioning that the so-called "level" of the present invention is subjectively determined by the user, so that different reference signals 143 can be set depending on the purpose of use. ? 11) The control unit 1 44 detects the difference between the voltage of the sensing signal 丨41 and the voltage of the reference signal 丨43, and the difference corresponds to the magnitude of the tilt angle 13. The piD control unit 144 performs a PID operation based on the difference to rotate a control signal 147 to the actuator 16. The tilt sensor 12 is disposed on a flat plate or a base (not shown), and the actuator 16 moves the flat plate/base according to the control signal 147 to adjust the tilt angle 13. In other words, after the actuator 16 moves the plate/base, the angle of inclination 13 is less than the angle of inclination 13 before the actuator 16 moves the plate/base. In the embodiment, the horizontal adjustment | set 1 () is to repeatedly adjust the tilt angle ' until the - level is reached. In this embodiment, the "horizontal" is in an equilibrium state, and the value of the corner i 3 is less than or equal to a first value (for example, 〇. i ϊν丄17 in the embodiment, the "level" is in an equilibrium state. When the difference between the sense 矾唬 141 and the reference signal 143 is less than or equal to the second value (eg, L°^01V), the actuator 16 is a DC motor, and the control signal 145 = the DC, up to 16 A control current, thereby controlling the DC motor 16 of the m $ 16 can also be a stepping motor, which is more precise control operation, and the relative manufacturing cost is also higher than that of the DC motor. 'A device containing electrical, mechanical, mechanical, thermal, optical, etc., to achieve braking, is within the scope of the present invention.

1257537 V. INSTRUCTION DESCRIPTION (8) ---- In one embodiment, the PID control unit 144 includes an analog PID control circuit. In another embodiment, PID control unit 144 includes a digital P:D control circuit. Referring to the drawings, the tilt sensor 12 has an analog, digital conversion (A/D COnverter) (not shown) for converting the detected tilt angle 13 and outputting a digital sense signal 141 to the processing unit 14. Such a ratio/digital converter has a precision of 12 bits, meaning that the value of the digital sense signal 141 can be from 1 to 4096 (2 to the power of 12). The reference unit 142 also provides a digital reference signal 143 (e.g., the value of the reference signal 143 of the set level is 200 0 ). The PID control unit 144 outputs a digital control signal 145 according to the difference between the digital sensing signal 141 and the digital reference signal 143. Processing unit 14 further includes a pulse generator 146. Pulse generator 146 generates a pulse signal 147 based on the digital control signal 145. This pulse signal 147 provides an actuator 16 - pulsed current, thereby controlling the operation of the actuator 16. For example, when the actuator 16 is a DC motor, the signals of 〇 and 1 are input at the positive and negative ends respectively, then the DC motor rotates forward; when the signals of 丨 and 〇 are input at the positive and negative ends respectively, the DC motor is reversed. Turn; input the signal of 丨 and 1 respectively at the positive and negative ends, then brake the DC motor so that it will not be over-adjusted due to inertia, and improve the accuracy. When the signals of 〇 and 丨 are input respectively at the positive and negative ends, and then the apostrophes of 1 and 1 are respectively input, the DC motor completes a pulse motion, and a pulse σίΐ 5 tiger can make the DC motor element move into a plurality of pulses. It should be understood that the method of controlling the pulse current can also achieve the equivalent: the performance of the stepping motor. In other embodiments, the processing unit 丨4 may be a side-use processor or a special-purpose processor, wherein the reference unit 142, the piD control unit 144, and the pulse generator 146 may be software, hardware, or Is soft

4AOCI04007TW.ptd Page 13 1257537 V. Description of invention (9) Implementation of a combination of body and hardware. Both Fig. 3 and Fig. 4 show that the level adjusting device 1 〇 repeatedly adjusts the tilt angle 1 3 until the change of the sensing signal 1 41 in a horizontal state. In Fig. 3, the PID control unit 144 selects a larger integral coefficient (integral-term coefficient: ^, thus accelerating the response of the actuator 16, but also causing greater oscillation. In Figure 4, the PID control unit 144 selects one of the smaller integral coefficients!^, thus causing less oscillation. In Figures 3 and 4, the PID control unit 144 performs a P ID operation according to the preset coefficient. However, as shown in Fig. 2c or Fig. 2d The processing unit 14 further includes an adjusting unit 148 for outputting an adjustment signal 149 to the PID control unit 1 44 to selectively adjust at least one coefficient of the pId operation, such as an integral coefficient K! Adjusting the signal 1 49 causes the integral coefficient K! to increase, so that the response of the actuator 16 to adjust the tilt angle 1 3 is accelerated. In addition, the adjustment signal 1 49 is output to adjust a proportional coefficient (pr〇p〇rf丨〇n -1 Erm coefficient) KP and / or a differential coefficient (differential-term coef f icient) KD means, in other words, computer hardware / software to implement this output adjustment number 1 4 9 to change the coefficient of p I d operation Means, also within the scope of the present invention The method of selecting the appropriate ρ丨D operation coefficient is well known to those skilled in the art and will not be described here. The adjustment unit 148 can be implemented by hardware, software, or a combination of software and hardware. 0,

1257537 V. Description of the Invention (ίο) As shown in Fig. 2c, the adjusting unit 丨48 outputs an adjustment signal 1 4 9 according to the value of the inclination angle 13. For example, in the first stage, when the value of the inclination angle i 3 is greater than 10 degrees, an adjustment signal 1 4 9 is output to increase the integral coefficient 1 ′ so that the actuator 1 6 § is tilted by 1 3 The response speeded up. In the second stage, when the value of the inclination angle 1 3 is less than 1 degree but greater than 3 degrees, the output adjustment signal 149 is stopped to the PID control unit 144, so that the PID control unit 144 adopts the preset integral coefficient K!. In the third stage, when the inclination angle 1 3 is less than 3 degrees, the adjustment signal 1 4 9 is output to reduce the integral coefficient & to avoid excessive oscillation of the actuator 16. In another embodiment, the adjustment unit 148 is based on the difference between the sensing signal 1 4 1 and the reference signal 1 4 3 to output an adjustment signal 丨49. For example, in the first stage, when the difference is greater than 〇·ΐν, the adjustment signal 149 is output to increase the integral coefficient Κ!, so that the actuator 16 adjusts the response of the inclination 1 3 to accelerate. In the second stage, when the difference is less than 〇· IV but greater than 〇· 〇 5V, the adjustment signal 1 49 is output to restore the preset integral coefficient]^ and increase the ratio coefficient ΚΡ . In the third stage, when the difference is less than 〇· 〇1 ν, the output adjustment signal 1 49 returns to the preset proportional coefficient Κρ and increases a differential coefficient Kd. As shown in FIG. 2d, the adjustment unit 148 is also based on the sense The difference between the test signal 丨4i and the reference signal 143 is to output the adjustment signal 149. However, the sensing signal 141 is a digital signal, and the corresponding value can be 1 to 4 〇 96 (2 to the power of 12). Reference signal 1 4 3 is also a digital signal, and the corresponding value is

4AOCI04007TW.ptd Page 15 1257537 V. Description of invention (11) 2 0 0 〇. For example, in the first stage, when the difference is greater than 5 〇 , the adjustment signal 149 is output to increase the integral coefficient center, and the response of the pulse generator 146 to cause the actuator 16 to adjust the tilt angle 1 3 is accelerated. In the second stage, when the difference is less than 100 but greater than 10, the adjustment signal 149 is output to restore 'the integral coefficient and the boosting force a ratio coefficient κΡ...: step: two, if the difference is less than 1 ,, then Take turns to adjust ρ Guangfu-hk, reserve number and increase a differential coefficient KD. ° ^ Revert to the preset ratio to limit the scope of the god and range protection. Although the invention is disclosed by the embodiment, such as i, lack of invention, anyone skilled in the art, right ... is not used internally All kinds of changes and 4 not == the saga of the application of the patent application park defined by the applicant

Page 16 4AOCI04007TW.ptd 1257537

V. [Simple Description of the Drawings] The drawings are to explain the present invention in conjunction with the specification. Figure 1 is a functional block diagram of a horizontal adjustment device in an embodiment; Figure 2b is a functional block diagram of a horizontal adjustment device in another embodiment; Figure 2c is an embodiment Figure 2d is a functional block diagram of a horizontal adjustment device with an adjustment unit in another embodiment; Figure 3 is a diagram showing the process of adjusting the inclination angle in an embodiment, the integral coefficient of which is greater than its integral The coefficient is compared with FIG. 4 to show the process of adjusting the tilt angle in an embodiment.] 〇 ※ Component symbol description 10 horizontal adjustment device 1 3 inclination angle 41 41 sensing signal 1 4 3 reference signal 1 4 5 control signal 1 4 7 pulse signal 1 4 9 adjustment signal 1 8 laser light source 1 2 inclination sensor 1 4 processing unit 142 reference unit 1 4 4P ID control unit 146 pulse generation crying 1 4 8 adjustment unit 1 6 actuator

Claims (1)

The invention relates to a horizontal adjustment device according to the fourth aspect of the invention, wherein the adjustment unit outputs the adjustment signal according to the value of the inclination angle. The level adjustment device of claim 4, wherein the adjustment unit outputs the adjustment signal based on a difference between the sensing signal and the reference signal. 7. The level adjusting device of claim 1, wherein the p ID control unit comprises an analog P ID control circuit. 8. The level adjusting device of claim 1, wherein the control unit comprises a digital PID control circuit. The level adjustment device of claim </ RTI> wherein the processing unit further comprises a pulse generator for generating a pulse signal according to the control signal; wherein the actuator is further based on the pulse signal. The tilting device is adjusted according to the first aspect of the invention, and the actuator is a stepping motor. II. The level adjusting device of claim 1, wherein the actuator is a DC motor. Page 19 J257537, the scope of application for patents 21 · If the control module of the application of the patent scope is the 18th item, the control module further includes an adjustment unit for outputting the adjustment signal to the PID control unit to adjust the In the PID operation, at least the 〆 coefficient is 0 2 2 . The control module of claim 18, wherein the adjustment unit outputs the adjustment signal according to the value of the inclination. 2 3 · The control module of claim 18, wherein the adjustment unit adjusts the signal by the output edge according to the difference between the sensing signal and the horizontal reference signal. 4AOCI04007TW.ptd Page 22