CN103543735A - Distributed type low-speed high-precision device and method for controlling astronomical telescope - Google Patents

Abstract

The invention discloses a distributed low-speed high-precision astronomical telescope control device and method, which are applied to the distributed high-precision control of the astronomical telescope. The control device consists of three parts: on-site control box, remote control box and PC console. The field control box contains the driver and the main operation panel; the remote control box contains the remote operation panel; the PC console is composed of an industrial computer with RS485 and operating software running on the industrial computer. The remote control box of the slave device and the PC console communicate with the main operation panel of the field control box of the master device through the RS485 bus to issue operation instructions to realize master-slave distributed control. The main operation panel then sends motion control instructions to the slave device driver through the CAN2.0 bus, and monitors the running status of the driver. The driver is connected to the motor line and feedback line in the telescope, and the motion control command is amplified and sent to the telescope drive motor, and the rational speed and position traction interpolation is realized inside the power amplifier to achieve precise control.

Description

A distributed low-speed high-precision astronomical telescope control device and method

technical field

The invention relates to the technical field of astronomical telescope control, in particular to the distributed low-speed and high-precision star tracking control of the astronomical telescope.

Background technique

In order to observe the stars in the sky and obtain the astronomical characteristics of the stars, it is hoped that the stars will remain still in the image of the telescope field of view without pixel drift. Due to the rotation of the earth, if the astronomical telescope is stationary, the stars will move from east to west at 15 arc seconds per second. To ensure that the stars remain stationary in the field of view, the telescope also needs to follow them from east to west at a speed of 15 arcseconds per second. Experiments show that the speed error between the two must not exceed 0.01 arcsecond/second, and the position of the star in the field of view image cannot be distinguished by the naked eye, and there is no pixel drift. Therefore, there are two difficulties in the control of astronomical telescopes. One is the extremely low speed, 15 arc seconds per second, which is almost invisible to the naked eye; the other is high speed stability requirements and long working hours. Usually, a star needs to be continuously observed. For hours, the stars cannot change in the field of view for several hours.

At the same time, there is a certain space distance between the studio of the astronomical telescope and the astronomical telescope. In order to achieve reliable work, the on-site control device of the general telescope is placed near the telescope, and the operator is usually at the workplace several meters or tens of meters away.

At present, the existing astronomical telescope control device realizes the low-speed control of the telescope through the speed ring of the driver, or realizes the low-speed control through the motion control card plus the driver. Fitting the speed of the stars accurately, but the actual instantaneous speed will keep changing, resulting in fluctuations in the image. At the same time, many astronomical telescopes are still stand-alone control systems, or have only one operation interface, which cannot be remotely controlled.

The invention discloses a novel distributed astronomical telescope control device and a low-speed and high-precision control method for the situation that the system requires high-precision and low-speed movement to realize the same operation as the star and requires multiple identical operation panels.

The advantage of the present invention is that the distributed control mode can connect many operation nodes at the same time. The method of position traction and driver interpolation not only eliminates the speed error, but also eliminates the integral of the speed error to achieve further stable speed control. At the same time, based on interpolation within the driver, accurate tracking of any rational fractional speed value is realized.

Contents of the invention

In order to achieve the above purpose, the present invention proposes a distributed low-speed high-precision astronomical telescope control device and method, which are applied to the control of astronomical telescopes. The device consists of three parts: field control box, remote control box and PC console. The field control box contains the driver and the main operation panel; the remote control box contains the remote operation panel; the PC console is composed of an industrial computer with an RS485 serial communication port and software running on the industrial computer.

Preferably, the main operation panel of the field control box in the control device is a master device, and the remote operation panel, PC console and driver of the remote control box are slave devices. The main operation panel communicates with the remote control box and PC console through the RS485 serial bus, and communicates with the driver through the CAN2.0 serial bus to realize master-slave distributed control.

Preferably, the main operation panel of the field control box in the control device continuously receives the button commands from the remote control box and the PC console, and integrates the user's key operation instructions to the main operation panel itself, and translates them into slave device driver functions. Understand the operating instructions for controlling the telescope and issue them to the driver; at the same time, the main operation panel periodically collects the current operating mode of the driver, monitors the status information of the driver, displays it on the main operation panel and publishes it to the remote control box and PC console show.

Preferably, the remote control box is used to respond to its own key operation and upload operation instructions to the main operation panel, receive the running status of the driver from the main operation panel, display its speed and status through the digital tube, and display the speed and status through the indicator light Operating status.

Preferably, the PC console implements a virtual operation panel through an operating software, responds to its own button operations and uploads operation instructions to the main operation panel, receives the running status of the driver from the main operation panel, and displays its speed and Status, the running status is displayed through the virtual indicator light.

Preferably, the driver in the field control box is used to respond to the control information sent by the main control board; control the motor rotation of the pan/tilt according to the speed parameters sent by the main control board; when an error occurs in the driver or the motor, send an error message to the main control board.

Preferably, the main operation panel, the remote control box and the PC console in the associated control device have exactly the same operation interface. The user inputs operation instructions to the astronomical telescope by operating the 4*3 button array; observes the operating status of the device through the four-digit digital tube and 4*3 LED lights; observes the power-on status through the power indicator light.

Preferably, the operation interface on the field control box, the remote control box, and the PC console in the control device, wherein the buttons include: plus and minus dial buttons, constant buttons, fast-forward buttons, slow-forward buttons, micro-motion plus buttons , fast rewind button, slow rewind button, micro-motion minus button, hold button, stop button, reset button; indicator lights include: alarm light, communication light, constant light, fast-forward light, slow-forward light, micro-motion plus light, Fast rewinding light, slow rewinding light, micro-motion reduction light, power light, stop light; digital display includes: four-digit seven-segment digital tube.

Preferably, in the operation interface, in the constant motion state, press the plus dial button, the constant motion speed will increase, and will be automatically saved in the internal flash, and the speed will be maintained, and will not be lost after power off, unless Press the addition and subtraction dial button again; press the subtraction dial button, the constant speed will decrease, and automatically save it in the internal flash, the speed will be maintained, and it will not be lost after restarting after power off, unless the addition and subtraction is pressed again Dial button. When the constant motion button is pressed, the control device enters a constant motion state, and the telescope is controlled to run at a constant speed of the earth's rotation speed, and the stars remain stationary within the field of view of the telescope. When the fast-forward button is pressed, the control device enters the fast-forward state, and the telescope is controlled to move forward quickly in the positive direction, that is, the opposite direction of the earth's rotation, so that the telescope can quickly search for stars; when the fast-forward button pops up, the control device returns to the constant motion state. When the slow-forward button is pressed, the control device enters the slow-forward state, and the telescope is controlled to advance slowly in the positive direction, that is, the opposite direction of the earth's rotation, so that the telescope slowly approaches to search for stars; when the slow-forward button pops up, the control device returns to the constant motion state. Press the micro-motion plus button, and the control device enters the micro-motion plus state, and controls the telescope to advance in the positive direction at the micro-motion speed, that is, the opposite direction of the earth's rotation, so that the telescope can approach and search for stars by micro-motion; the micro-motion plus button pops up, and the control device returns Perpetual state. When the rewind button is pressed, the control device enters the rewind state, and the telescope is controlled to move forward quickly in the negative direction, that is, the direction of the earth's rotation, so that the telescope can quickly search for stars; when the rewind button pops up, the control device returns to the constant motion state. When the slow back button is pressed, the control device enters the slow back state, and the telescope is controlled to advance slowly in the opposite direction, that is, the direction of the earth's rotation, so that the telescope slowly approaches to search for stars; when the slow back button pops up, the control device returns to the constant motion state. Press the micro-minus button, the control device enters the micro-minus state, and control the telescope to advance in the opposite direction at the micro-motion speed, that is, the direction of the earth's rotation, so that the telescope can approach and search for stars with micro-motion; the micro-minus button pops up, and the control device returns to constant dynamic state. When the stop button is pressed, the telescope will stop moving. The reset button is used to reset the operation interface where the button is located. When the alarm indicator light is on, it indicates a fault state. The communication indicator light is used to indicate the current communication status. When it is in a normal state, the indicator light will be on and off alternately; When the constant motion indicator light is on, it indicates the constant motion state; when the fast forward indicator light is on, it indicates the fast forward state; when the slow motion indicator light is on, it indicates the slow forward state; When the fast rewind indicator is on, it indicates the fast rewind state; when the slow rewind indicator is on, it indicates the slow rewind state; when the inching minus indicator is on, it indicates the inching minus state; the power indicator is used to indicate the working state, , the light is always on. When the stop indicator light is on, it indicates a stop state. The digital tube displays different speed values according to different states. When in the constant motion state, it displays the constant motion speed value; in the fast forward state, it displays the fast forward speed value, and so on.

Preferably, the internal operation mode of the driver in the field control box is: firstly power on and initialize, and then perform hardware self-test after initialization, enter the idle state if there is no problem in the self-test, and enter the error state if there is an error. After the main operation panel sends corresponding commands, the driver will switch from idle state to running state. In the running state, the drive will work with a position loop. The main operator panel can also send commands to make the drive re-test itself. When the run state encounters an error, it enters the error state. After troubleshooting the cause of the error, the system can be returned to the idle state through the error clearing command. When it is desired to stop, the main operation panel sends a stop command, and the drive enters the stop state. It can return to the idle state if it receives a start command during the stop state.

Preferably, the low-speed high-precision control method of the astronomical telescope realizes high-stable low-speed control through the position pulling method built into the driver, and a rational fractional speed value is given. It is stipulated that the denominator is the cycle number of the position loop, and the numerator is the number of displacement pulses that must be walked under these position cycle numbers. In a single cycle of each position loop, linear interpolation is performed to generate the required position command, which is sent to the position loop to realize the closed-loop position servo; after completing the number of denominator cycles, a new round of speed cycle is restarted to realize Position traction, the slope of position versus time is the velocity value we need.

Preferably, in the low-speed and high-precision control method of the telescope, when a speed command of a rational fraction is issued and an execution command is issued, initialization is first performed: setting the reference position command as a feedback position command. According to the size of the velocity denominator and the velocity numerator, it can be divided into two cases. When the velocity denominator is greater than the velocity numerator, this is defined as a special interpolation mode; when the velocity numerator is greater than the velocity denominator, this is defined as a normal interpolation mode.

Preferably, in the low-speed and high-precision control method of the telescope, in the special interpolation mode, the initial interpolation parameter C is the speed denominator minus twice the absolute value of the speed numerator, and the interpolation parameter C1 is negative twice the speed numerator absolute value The value and the interpolation parameter C2 are twice the difference between the speed denominator minus the absolute value of the speed numerator. In the normal interpolation mode, the initial interpolation parameter C is the absolute value of the speed numerator minus twice the speed denominator, the interpolation parameter C1 is the negative double speed denominator, and the interpolation parameter C2 is the absolute value of the speed numerator minus The difference in velocity denominator is multiplied by 2. The numerator counter and denominator counter are cleared.

Preferably, in the low-speed high-precision control method of the telescope, after the initialization is completed, the following steps are performed in the timer period of the position loop: under normal interpolation, if the numerator counter is greater than or equal to the speed numerator, end this round of speed For the interpolation of the denominator cycle number, the numerator counter and the denominator counter are cleared, C resets the absolute value of the speed numerator minus twice the speed denominator, and a new round of interpolation of the speed denominator cycle number will be started; if the numerator counter is smaller than the speed numerator , to judge whether the parameter C is positive or negative. If C is greater than zero, the numerator counter is continuously increased by 1, and the position command is also increased or decreased by 1. The parameter C is assigned as C:=C+C1 until C is less than zero. If C is already less than zero , then both the numerator and denominator counters increase by 1, the position command increases or decreases by 1, and the parameter C is assigned as C:=C+C2.

Preferably, in the low-speed and high-precision control method of the telescope, after the initialization is completed, the following steps are performed in the timer period of the position loop: in the special interpolation mode, if the denominator counter is greater than or equal to the speed denominator, end this round of speed For the interpolation of the denominator cycle number, the numerator counter and the denominator counter are cleared, C resets the speed denominator minus twice the absolute value of the speed numerator, and will start the next round of interpolation of the speed denominator cycle number; if the denominator counter is smaller than the speed denominator , then first judge whether the parameter C is positive or negative. If C is less than zero, the counting denominator will increase, and the position command will increase or decrease by 1. The parameter C will be assigned C:=C+C2; if C is greater than zero, the denominator count value will be increased by 1. , the parameter C is assigned the value C:=C+C1.

Preferably, in the low-speed and high-precision control method of the telescope, the position command generated by linear interpolation is used as an input command signal in the position loop cycle of the driver to the position loop, and the driver then operates the position loop to realize low-speed high-precision speed based on position traction control.

As can be seen from the above scheme, the present invention has the following advantages:

One is to adopt a special master-slave control mode. This mode distinguishes real-time communication from non-real-time communication, and realizes multi-node hierarchical distributed control. Between the main operation panel and the driver, CAN2.0 is used to realize real-time and reliable communication; while the main panel and other operation interfaces use RS485 bus to realize long-distance multi-node master-slave control. However, if the driver is the main driver and the keypad is the slave, the driver will be occupied by too many system resources in terms of communication, which will reduce the real-time performance of the driver.

Second, the main operation panel and the on-site control box and PC console have completely consistent operation interface, which makes the operation simple and reliable, not only realizes multi-point control, but also realizes the purpose of multi-point monitoring. It is convenient for further expansion of the system.

3. The linear interpolation method of position pulling speed with rational fraction built in the drive and running at the same frequency as the position loop of the drive realizes low-speed high-precision telescope follow-up control without cumulative error.

Description of drawings

Figure 1 Schematic diagram of system composition

Figure 2 Operation panel interface layout

Figure 3 Flowchart of the main operation panel control software

Figure 4 Remote Control Box and PC Console Software Flowchart

Figure 5 Driver software flow chart

Figure 6 Flow chart of position loop with built-in linear interpolation

Figure 7 Initialization of linear interpolation

Figure 8 One execution of normal interpolation mode

Figure 9 One execution of special interpolation mode

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the implementation manner of the present invention will be further described in detail below in conjunction with the accompanying drawings.

1. System composition

Fig. 1 is a structural schematic diagram of the distributed low-speed high-precision astronomical telescope control device of the present invention. The device consists of a field control box, a remote control box and a PC console.

The field control box contains the driver and the main operation panel.

The remote control box contains the remote operation panel.

The PC console is composed of an industrial computer and software running on the industrial computer.

The main operation panel of the field control box has 1 CAN2.0 communication interface and 1 RS485 interface.

The driver of the field control box has a CAN2.0 communication interface.

The remote operation panel has 1 RS485 interface.

PC console has RS485 communication interface.

The main operation panel of the field control box and the driver realize real-time communication through CAN2.0. In real-time communication, the main operation panel is the master device, and the driver is the slave device.

The main operation panel of the field control box and the remote control box and PC console realize multi-node long-distance communication through RS485. In RS485 communication, the main operation panel is the master device, and the remote control box and PC console are slave devices.

The driver of the field control box is connected with the brush drive motor of the astronomical telescope. The connection line between the driver and the brushed motor includes two motor lines and the encoder feedback of the motor.

2 operation panel

Fig. 2 is the human-machine interface of the main operation panel, the remote control box and the PC control panel in the distributed low-speed high-precision astronomical telescope control device of the present invention.

Above the man-machine interface is a four-digit eight-segment digital tube, which is used to display the speed information in the current running state.

Below the eight-segment digital tube is a 3*4 array of keys. Next to the buttons, there are corresponding LED indicators. From left to right, from top to bottom, the keys are plus key, minus key, constant key, fast forward key, slow forward key, micro plus key, fast rewind key, slow rewind key, micro minus key, reserve , stop key, reset key. From left to right, from top to bottom, the LED lights are alarm light, communication light, constant motion light, fast forward light, slow forward light, micro motion plus light, fast rewind light, slow back light, micro motion minus light, Power light, stop light.

In the state of constant motion, press the plus dial button, the constant speed will increase and be automatically saved in the internal flash, the speed will be maintained, and it will not be lost after restarting after power failure, unless the plus or minus dial button is pressed again; Press the minus dial button, the constant speed will decrease, and it will be automatically saved in the internal flash, and the speed will be maintained, and it will not be lost after restarting after power failure, unless the plus and minus dial button is pressed again.

When the constant motion button is pressed, the control device enters a constant motion state, and the telescope is controlled to run at a constant speed of the earth's rotation speed, and the stars remain stationary within the field of view of the telescope. The constant motion button pops up, and the constant motion state does not change.

When the fast-forward button is pressed, the control device enters the fast-forward state, and the telescope is controlled to move forward quickly in the positive direction, that is, the opposite direction of the earth's rotation, so that the telescope can quickly search for stars; when the fast-forward button pops up, the control device returns to the constant motion state.

When the slow-forward button is pressed, the control device enters the slow-forward state, and the telescope is controlled to advance slowly in the positive direction, that is, the opposite direction of the earth's rotation, so that the telescope slowly approaches to search for stars; when the slow-forward button pops up, the control device returns to the constant motion state.

Press the micro-motion plus button, and the control device enters the micro-motion plus state, and controls the telescope to advance in the positive direction at the micro-motion speed, that is, the opposite direction of the earth's rotation, so that the telescope's micro-motion speed is close to searching for stars; the micro-motion plus button pops up, and the control device Return to the constant state.

When the rewind button is pressed, the control device enters the rewind state, and the telescope is controlled to move forward quickly in the negative direction, that is, the direction of the earth's rotation, so that the telescope can quickly search for stars; when the rewind button pops up, the control device returns to the constant motion state.

When the slow back button is pressed, the control device enters the slow back state, and the telescope is controlled to advance slowly in the opposite direction, that is, the direction of the earth's rotation, so that the telescope slowly approaches to search for stars; when the slow back button pops up, the control device returns to the constant motion state.

Press the inching minus button, the control device enters the inching minus state, and controls the telescope to advance in the negative direction at the inching speed, that is, the direction of the earth's rotation, so that the telescope's inching speed is close to searching for stars; the inching minus button pops up, and the control device returns Perpetual state.

When the stop button is pressed, the telescope will stop moving.

The reset button is used to reset the operation interface where the button is located.

When the alarm indicator light in the figure is on, it indicates a fault state.

The communication indicator light is used to indicate the current communication status. When it is in the normal communication status, the indicator light will be on and off alternately; when it is in the error communication status, it will flash and off to indicate the error status.

When the constant motion indicator light is on, it indicates a constant motion state.

When the fast-forward indicator light is on, it indicates fast-forward status.

When the slow rewind indicator is on, it indicates the slow rewind state.

When the inching plus indicator light is on, it indicates the inching plus state.

When the rewind indicator light is on, it indicates fast rewind status.

When the slow-forward indicator light is on, it indicates the slow-forward state.

When the inching minus indicator light is on, it indicates the inching minus state.

When the power light is on, it indicates that the system is powered on.

When the stop indicator light is on, it means it is in a stopped state.

The digital tube displays different speed values according to different states. When in the constant motion state, it displays the constant motion speed value; in the fast forward state, it displays the fast forward speed value, and so on.

3. The main operation panel controls the software flow

Fig. 3 is a flow chart of the main control software of the present invention, running on the main operation panel of the field control box.

After the system is reset, it enters the initialization state. First, the peripherals and internal variables are initialized, and the LEDs, digital tubes, and keys are in the initial state, and wait for the driver to complete the initialization and self-test work. In the initialization state, the keys are ineffective.

After the initialization is complete, the system enters the self-test state. In the self-test state: communicate with the drive to ensure that the communication is normal. Read the internal state of the drive, if the drive works normally, it will be in the state of power failure, and the main operation panel will write the current number of code discs; if the drive is not normal, the main operation panel will alarm according to the error status of the drive, prompting an error, and wait for the technician After troubleshooting, the self-inspection work is completed. In the self-test state, the key does not work.

The system self-test is normal, or press the constant motion key in the stop state, or press the fast forward, fast reverse, slow forward, slow reverse, inching plus, inching minus buttons in the search state, the system will issue a strengthening electric command, into a state of perpetual motion. In the constant motion state, the main operation panel will write the constant motion running parameters, and the system will move forward at the default constant speed. However, if the user presses the plus or minus key, the speed can be fine-tuned, and the fine-tuning has an upper limit and a lower limit. At this time, the main operation panel will issue a new speed command. In the constant state, the main operation panel will query the state of the driver periodically. If an error occurs, the main operation panel will enter the error state and give an alarm.

In the state of constant motion or stop, if you press the keys of fast forward, slow forward, fast rewind, slow rewind, inching plus, inching minus, etc., it will enter the search state. In the search state, it will run at the speed of fast forward, slow forward, fast reverse, slow reverse, jog plus, jog minus, etc. When the corresponding button pops up, it will re-enter the constant motion state. In the search state, the main operation panel will query the state of the drive periodically, and if an error occurs, the main operation panel will enter the error state and give an alarm.

If the stop button is pressed, it enters the stop state. In the stopped state, a command will be issued to stop the drive and cut off the strong power. In the search state, the main operation panel will query the state of the drive periodically, and if an error occurs, the main operation panel will enter the error state and give an alarm.

When the system is in the state of self-test, constant motion, search, stop, etc., if there is an operation error, it will enter the error state and give instructions. Wait for user to troubleshoot. After the troubleshooting is completed, the main operation panel can issue a clearing command. When clearing is successful, the system will jump to stop state.

4. Remote control box and PC console software process

Fig. 4 is a flow chart of the software modules running on the remote operation box and the PC console, which perform the same functions. Their process is as follows:

First, the system is reset, and then initialized to give the initial state of each button, digital tube and indicator light. After initialization, enter the main scan cycle.

In the main scan cycle, firstly, it is continuously inquired whether the flag bit of the main scan cycle is set to 1. If it is, it will read the state of all current key values, compare it with the key value of the previous cycle, and obtain specific key information according to the change of the key value. If there is no key change, no processing will be done; if any key is pressed or popped up, the key information will be sent to the host computer, which is the main operation panel. When the button information is checked, or the main scan cycle flag is zero, it will check whether there is a serial port message issued by the host computer; if there is, it will analyze the corresponding communication protocol to obtain the current operating status of the system, and update the digital tube according to the latest speed information Display, and update the state of the indicator light.

5. Driver software flow chart

Please refer to FIG. 5 , which is a flowchart of the driver software of the present invention.

After the system is powered on, the driver performs initialization work, first initializes the peripherals, and then initializes the system.

After initialization, carry out self-inspection work, check whether each interface and MOS tube are working normally, after self-inspection is completed, when everything is normal, enter the idle state. When a failure occurs, enter the error state.

After entering the idle state, the power tube is still closed, and the idle state can reach the running state and can be forced to self-test again.

Entering the running state, the system automatically enters the position loop state, and the rational fractional speed interpolation based on position traction will run inside the position loop. When the operation is over, it can return to the idle state or enter the shutdown state.

After entering the shutdown state, all peripherals are turned off, and the system cannot return to the running state, only to be powered on again.

After entering the error state, it will first give a corresponding prompt according to the error number. Will return to idle state when the fault is corrected.

6. Rational fractional speed operation of position-driven linear interpolation

Fig. 6 is a flow chart of the position-driven rational fractional speed linear interpolation method inside the driver. When the drive enters the running state, it automatically enters the linear interpolation position loop mode. In the linear interpolation position loop mode, wait for the position of the position loop period indicator to be 1, indicating that the position loop period has arrived. When the position loop period is up, the linear interpolation method will be executed to generate the position command required by the position loop and send it to the position loop. The position loop performs closed-loop control according to the position command and actual position feedback to realize the position servo. The combination of linear interpolation and position loop realizes low-speed and high-precision rational fractional speed servo.

Fig. 7 is the initialization process of linear interpolation. This process runs in the link of "executing a linear interpolation" in Fig. 6 .

When a new speed command arrives or enters the position loop operation for the first time, it will enter the initialization process of linear interpolation. First, we initialize the speed numerator and speed denominator of the command according to the speed command issued. The velocity numerator can be positive or negative, and the velocity denominator is always positive. And assign the position feedback to the position command. And judge the size of the speed numerator and the speed denominator.

When the speed numerator is greater than the speed denominator, enter the normal interpolation mode. In normal interpolation mode, the initial interpolation parameter C is the absolute value of the speed numerator minus twice the speed denominator, the interpolation parameter C1 is the negative double speed denominator, and the interpolation parameter C2 is the absolute value of the speed numerator minus the speed The difference in denominator is multiplied by 2.

When the speed denominator is greater than the speed numerator, enter the special interpolation mode. In the special interpolation mode, the initial interpolation parameter C is the absolute value of the speed denominator minus twice the speed numerator, the interpolation parameter C1 is the negative double the absolute value of the speed numerator, and the interpolation parameter C2 is the speed denominator minus the speed Twice the difference in absolute value of the numerator.

After initializing C, C1 and C2, the numerator counter and denominator counter are cleared. Linear interpolation initialization is completed.

Figure 8 is an execution of the normal interpolation mode. When the drive enters the normal interpolation mode, it first judges whether the numerator counter is greater than or equal to the speed numerator. If it is, it means that the last round of rational fractional speed has been executed, the executed distance is the absolute value of the speed numerator, the execution time is the speed denominator, and a new round of rational fractional speed will be executed, and the numerator counter will be cleared at this time , the initialization parameter C is the difference between the absolute value of the velocity numerator minus twice the velocity denominator, and a new round of interpolation starts.

If the numerator counter is smaller than the velocity numerator, or the initialization of a new round of interpolation has been completed, the loop judges whether C is greater than zero. If C is greater than zero, judge whether the numerator counter is greater than or equal to the speed numerator, if it is greater than or equal to, then end this interpolation, if less than, then add 1 to the numerator counter, if the speed numerator is greater than zero, add 1 pulse to the position command, if the speed numerator Less than zero position command reduces 1 pulse, and updates parameter C, C is equal to C plus C1, and continues to loop to judge whether C is greater than zero, until C is less than or equal to zero.

If C is less than or equal to zero, judge whether the numerator counter is greater than the speed numerator, if greater than or equal to, end this interpolation; if less than, then add 1 to the numerator counter, add 1 to the denominator counter, if the speed numerator is greater than zero, add 1 pulse to the position command , if the speed numerator is less than the zero position command, reduce 1 pulse, and update the parameter C, C is equal to C plus C2, and end this interpolation.

Figure 9 is an execution of the special interpolation mode. First judge whether the denominator counter is less than the speed denominator.

If it is, continue to judge whether C is less than or equal to zero. If it is less than or equal to zero, the denominator counter increases by 1. If the speed numerator is greater than zero, the position command increases by 1. If the speed numerator is less than zero, the position command decreases by 1. C is assigned C plus C2 , end this interpolation; if C is greater than zero, the denominator counter increases by 1, C is assigned C plus C1, and this interpolation ends.

If not, the numerator and denominator counters are cleared, C is initialized to the difference between the speed denominator minus 2 times the absolute value of the speed numerator, and this interpolation ends.

All or part of the technical solutions provided by the above embodiments can be realized by software programming, and the software program is stored in a readable storage medium, such as a hard disk, an optical disk or a floppy disk in a computer.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.

Claims (10)

1. a distributed low-speed high-precision astronomical telescope control device, said device comprising a field control box, a remote control box and a PC console, The field control box includes a driver and a main operation panel; The remote control box includes a remote operation panel; The PC console includes an industrial computer with an operation panel and a communication port; It is characterized in that the main operation panel of the field control box is a master device, and the remote operation panel, the PC console, and the driver of the remote control box are slave devices. 2. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 1, is characterized in that, described main operation panel communicates with described remote control box, described PC console by RS485 serial bus, Communicate with the driver through the CAN2.0 serial bus to realize master-slave distributed control. 3. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 2, is characterized in that, described main operation panel receives the key instruction from described remote control box and described PC console uninterruptedly, And integrate the user's key operation instructions on the main operation panel itself, translate them into operation instructions for controlling the astronomical telescope that the driver of the slave device can understand, and send them to the driver; at the same time, the main operation panel periodically Collect the current operating mode of the driver, monitor the status information of the driver, display it on the main operation panel and publish it to the remote control box and the PC console for display. 4. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 3, is characterized in that, described remote control box is used for responding to the button operation of itself and uploads operation order to described main operation panel, receives The operating status of the driver from the main operation panel, displaying its operating status; The PC console responds to its own button operations through its operation panel and uploads operation instructions to the main operation panel, receives the operating status of the driver from the main operating panel, and displays its operating status; The driver in the field control box is used to respond to the control information sent by the main control board; the motor rotation of the pan tilt is controlled according to the speed parameters sent by the main control board; when an error occurs in the driver or the motor, an error message is sent to the main control board plate. 5. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 4, is characterized in that, the main operation panel of described field control box, described remote control box and described PC console have identical Operation interface. 6. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 5, is characterized in that, the button of the operation interface on described field control box, remote control box, PC console comprises: Addition and subtraction dial buttons, constant button, fast forward button, slow forward button, inching plus button, fast rewind button, slow rewind button, inching minus button, hold button, stop button, reset button; The indicator lights on the operation interface include: Alarm light, communication light, constant motion light, fast forward light, slow forward light, micro motion plus light, fast back light, slow back light, micro motion minus light, power light, stop light; The digital display of the operation interface includes a four-digit seven-segment digital tube. 7. A kind of distributed low-speed high-precision astronomical telescope control device according to claim 6, characterized in that: In the state of constant motion, press the plus dial button, the constant speed will increase, and will be automatically saved in the internal flash, the speed will be maintained, and will not be lost after restarting after power failure, unless the plus and minus dial button is pressed again; Press the minus dial button, the constant speed will decrease, and automatically save it in the internal flash, the speed will be maintained, and it will not be lost after restarting after power failure, unless the plus and minus dial button is pressed again; Press the constant motion button, the control device enters the constant motion state, controls the telescope to run at a constant speed of the earth's rotation speed, and the stars remain stationary within the field of view of the telescope; Press the fast-forward button, the control device enters the fast-forward state, and controls the telescope to move forward quickly in the positive direction, that is, the opposite direction of the earth's rotation, so that the telescope can quickly search for stars; the fast-forward button pops up, and the control device returns to the constant motion state; When the slow-forward button is pressed, the control device enters the slow-forward state, and the telescope is controlled to advance in the positive direction at a slow speed, that is, the opposite direction of the earth's rotation, so that the telescope slowly approaches to search for stars; when the slow-forward button pops up, the control device returns to the constant motion state; Press the micro-motion plus button, and the control device enters the micro-motion plus state, and controls the telescope to advance in the positive direction at the micro-motion speed, that is, the opposite direction of the earth's rotation, so that the telescope can approach and search for stars by micro-motion; the micro-motion plus button pops up, and the control device returns Perpetual state; When the rewind button is pressed, the control device enters the rewind state, and the telescope is controlled to quickly move forward in the negative direction, that is, the direction of the earth's rotation, so that the telescope can quickly search for stars; when the rewind button pops up, the control device returns to the constant motion state; Press the slow back button, the control device enters the slow back state, control the telescope to advance slowly in the opposite direction, that is, the direction of the earth's rotation, and let the telescope slowly approach to search for stars; the slow back button pops up, and the control device returns to the constant motion state; Press the micro-minus button, the control device enters the micro-minus state, and control the telescope to advance in the opposite direction at the micro-motion speed, that is, the direction of the earth's rotation, so that the telescope can approach and search for stars with micro-motion; the micro-minus button pops up, and the control device returns to constant dynamic state; Press the stop button, the telescope will stop moving; The reset button is used to reset the operation interface where the button is located; When the alarm indicator light is on, it indicates a fault state; The communication indicator light is used to indicate the current communication status. When it is in the normal state, the indicator light will be on and off alternately; when it is in the error state, it will flash and off to indicate the error communication state; When the constant motion indicator light is on, it indicates a constant motion state; When the fast-forward indicator light is on, it indicates the fast-forward state; When the slow-forward indicator light is on, it indicates the slow-forward state; When the inching plus indicator light is on, it indicates the inching plus state; When the fast rewind indicator light is on, it indicates fast rewind state; When the slow back indicator light is on, it indicates the slow back state; When the inching minus indicator light is on, it indicates the inching minus state; The power indicator light is used to indicate the working status, when the power is turned on, the light is always on; When the stop indicator light is on, it indicates a stop state; The digital tube displays different speed values according to different states. When in the constant motion state, it displays the constant motion speed value; in the fast forward state, it displays the fast forward speed value. 8. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 7, is characterized in that, the driver in the described scene control box can carry out following internal operating mode: First power on and initialize. After initialization, hardware self-test will be performed. If there is no problem in the self-test, it will enter the idle state, and if an error occurs, it will enter the error state; After the main operation panel sends the corresponding command, the driver will switch from the idle state to the running state; in the running state, the driver will work with a position loop; the main operation panel can also send commands to make the driver re-check itself; When the running state encounters an error, it will enter the error state; after the cause of the error is checked, the system can return to the idle state through the error clearing command; When it is desired to stop, the main operation panel sends a stop command, and the drive enters the stop state; It can return to the idle state if it receives a start command during the stop state. 9. A kind of distributed low-speed high-precision astronomical telescope control device according to claim 8, characterized in that, the driver can perform linear interpolation within the period of each position loop to generate the required position command, Send it to the position loop to realize the closed-loop position servo. 10. a kind of distributed low-speed high-precision astronomical telescope control device according to claim 9, is characterized in that, when described driver has normal interpolation mode and special interpolation mode; In the normal interpolation mode, the drive can perform the following steps: First judge whether the numerator counter is greater than or equal to the speed numerator; if it is, it indicates that the last round of rational fractional speed has been executed, the executed distance is the absolute value of the speed numerator, and the execution time is the speed denominator, and a new round of rational fractional speed will be carried out Fractional speed execution, at this time the numerator counter is cleared, the initialization parameter C is the absolute value of the speed numerator minus twice the difference between the speed denominator, and a new round of interpolation starts; If the numerator counter is smaller than the velocity numerator, or the initialization of a new round of interpolation has been completed, loop to determine whether C is greater than zero; if C is greater than zero, determine whether the numerator counter is greater than or equal to the velocity numerator, and if it is greater than or equal to, end this interpolation Complement, if it is less than, add 1 to the numerator counter, if the speed numerator is greater than zero, add 1 pulse to the position command, if the speed numerator is less than zero, decrease 1 pulse to the position command, and update the parameter C, C is equal to C plus C1, and continue to cycle Determine whether C is greater than zero until C is less than or equal to zero; If C is less than or equal to zero, judge whether the numerator counter is greater than the speed numerator, if greater than or equal to, end this interpolation; if less than, then add 1 to the numerator counter, add 1 to the denominator counter, if the speed numerator is greater than zero, add 1 pulse to the position command , if the speed numerator is less than the zero position command, reduce 1 pulse, and update the parameter C, C is equal to C plus C2, and end this interpolation; In the special interpolation mode, the drive can perform the following steps: First judge whether the denominator counter is smaller than the speed denominator; If it is, continue to judge whether C is less than or equal to zero. If it is less than or equal to zero, the denominator counter increases by 1. If the speed numerator is greater than zero, the position command increases by 1. If the speed numerator is less than zero, the position command decreases by 1. C is assigned C plus C2 , end this interpolation; if C is greater than zero, the denominator counter increases by 1, C is assigned C plus C1, and this interpolation ends; If not, the numerator and denominator counters are cleared, C is initialized to the difference between the speed denominator minus 2 times the absolute value of the speed numerator, and this interpolation ends.

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