CN115765541A - Motor control system and control method of wireless laser communication platform - Google Patents

Abstract

The invention discloses a motor control system of a wireless laser communication platform, which comprises a two-dimensional rotary table, wherein a processing controller, a horizontal stepping motor connected with the processing controller through a horizontal stepping motor driver and a pitching stepping motor connected with the processing controller through a pitching stepping motor driver are arranged on the two-dimensional rotary table, the horizontal stepping motor and the pitching stepping motor are respectively connected with a horizontal magnetic encoder and a pitching magnetic encoder, and the rotation angles of the horizontal stepping motor and the pitching stepping motor are respectively fed back to the processing controller through the horizontal magnetic encoder and the pitching magnetic encoder. The system has low cost, good stability and high positioning precision, and the method is simple and reliable, and easy to operate, and can meet the requirements of the APT system on the positioning stability and high precision of the stepping motor.

Description

Motor control system and control method of wireless laser communication platform

Technical Field

The invention relates to a motor control technology, in particular to a motor control system and a control method of a wireless laser communication platform.

Background

In wireless laser communication, in order to establish a stable communication link, an Acquisition, pointing and Tracking (APT) system with high precision and high stability is required, and a motor control system is the basis and the premise for realizing the APT technology.

A stepper motor, as a digitally controlled motor, can convert received electrical pulses into angular displacement. The open-loop control system of the stepping motor has no accumulated error, is easy to realize high-precision positioning, is widely applied to the field of precision control, and has simple structure and low cost. However, the traditional stepping motor open-loop control system has an oscillation area, which is easy to generate larger fluctuation and oscillation, and due to the influence of the structure, performance and load of the motor system, the problems of insufficient moment, blocking, step loss, locked rotor and the like of the stepping motor can be caused, and the requirements of the wireless laser communication APT system on occasions with higher requirements on precision and stability can not be met.

The Chinese patent application number of 201821309153.4 discloses a stepping motor closed-loop control system, which only connects a sampling resistor in series with a stepping motor coil in a sampling circuit, and achieves the purpose of continuously driving a stepping motor to rotate according to the collected voltage; the technical scheme includes that whether speed loop control is started or not is judged by setting a control coefficient and combining a position loop expected value, so that the speed loop control is adopted when the stepping motor is far away from a target value. The requirements of stability and high precision of positioning of the stepping motor of the wireless laser communication APT system can not be met no matter the traditional stepping motor open-loop control method or some existing closed-loop control methods.

Disclosure of Invention

The invention aims to provide a motor control system and a motor control method of a wireless laser communication platform aiming at the defects of the prior art. The system has low cost, good stability and high positioning precision, and the method is simple and reliable, and easy to operate, and can meet the requirements of the APT system on the positioning stability and high precision of the stepping motor.

The technical scheme for realizing the purpose of the invention is as follows:

the utility model provides a motor control system of wireless laser communication platform, including the two-dimensional revolving stage, be equipped with processing controller on the two-dimensional revolving stage and pass through the horizontal step motor that horizontal step motor driver is connected and the every single move step motor that connects through every single move step motor driver with processing controller, horizontal step motor and every single move step motor connect horizontal magnetic encoder and every single move magnetic encoder respectively, horizontal step motor and every single move step motor's turned angle is fed back to processing controller by horizontal magnetic encoder and every single move magnetic encoder respectively, use the controller as the core, the dotted line in figure 1 represents magnetic induction, the function of controller is acquireed the target position, the number of pulses is calculated, driving motor motion, and receive feedback information, control the motion mode of each process, the driver received direction signal and pulse information subdivide driving motor, magnetic encoder feedback position information gives processing controller, the two-dimensional revolving stage is responsible for the rotation function.

The horizontal stepping motor and the pitching stepping motor are both direct-current two-phase stepping motors and respectively control the horizontal shaft and the pitching shaft.

The horizontal stepping motor driver and the pitching stepping motor driver are 256 subdivision drivers.

The horizontal magnetic encoder and the pitching magnetic encoder are both 4096-wire magnetic encoders.

A motor control method of a wireless laser communication platform comprises a motor control system of the wireless laser communication platform, the method comprises the control mode of combining open-loop control and closed-loop feedback control to carry out time-sharing control on a motor to realize stable high-precision positioning, when a wireless laser communication APT system works, the wireless laser communication APT system is divided into three stages of capturing, aligning and tracking, and different motor control strategies are respectively adopted for the three stages, wherein the capturing and aligning stages need to have a stable operation process and ensure enough torque, and a horizontal magnetic encoder and a pitching magnetic encoder do not need to feed back angle information, the motor speed and the driving current are controlled according to the capturing and aligning conditions of the system to improve the operation stability and the torque, so that the efficiency of capturing and aligning targets is also ensured; and need higher positioning accuracy in the tracking stage to guarantee to establish reliable communication link, detect out-of-step and overshoot deviation through the code wheel, compensate the deviation that the motor out-of-step and overshoot produced, can improve the tracking accuracy of the motor, need to adopt closed-loop control, including the following steps:

1) Open-loop control: the method specifically comprises the following steps:

1-1) firstly, when the motor is started, the motor is started by adopting a control mode of large current and slow start, so that the starting with large torque and low speed is realized, and the locked rotor and the step-out are prevented from being generated during the starting;

1-2) the controller of the scanning capturing process controls the position, the speed and the current, the speed is set to be an accelerating stage from 0 to t1, the speed is increased to the maximum value Vt from 0, the speed is uniformly increased from 1 to 2, and the speed is reduced to 0 from Vt from 2 to 3, so that when the motor is accelerated or decelerated, the stable operation in the scanning process due to step loss and overshoot is prevented, wherein t1, t2, t3 and Vt are debugged and selected according to the actual operation stability of the system;

1-3) when a target is captured to enter an alignment process, continuously converting the target position deviation into the number N (or the number of pulses) of steps required to be operated by the motor, sending the number N (or the number of pulses) to the motor for driving, and driving the motor to rotate to align the target;

2) Closed loop feedback control, adopt the three closed loop control mode of electric current, speed and position, if the target does not have the motion, the motor keeps static, the motor maintains the static moment of load, if the target has the motion, the motor can follow the rotation, compare horizontal magnetic encoder and every single move magnetic encoder feedback value and target position value this moment, if the deviation value is greater than precision error requirement value, control the motor and reverse to the target position, need calculate the position deviation according to the position value that horizontal magnetic encoder and every single move magnetic encoder feedback this moment and obtain new operation step number N, reduce motor speed simultaneously, prevent that continuous overshoot and backlash from causing system oscillation, make and continuously keep the alignment state, the shock phenomenon that can not appear continuously.

The technical scheme adopts a control mode combining open-loop control and closed-loop feedback control, the control method is simple and reliable, and the research and development cost is reduced;

the technical scheme obviously overcomes the defects of insufficient torque, blockage, step loss, locked rotor and the like in the running process of the stepping motor in the prior art, so that the system runs more stably, the target capturing efficiency of the APT system is improved, and the tracking precision is improved.

The system has low cost, good stability and high positioning precision, and the method is simple and reliable, and easy to operate, and can meet the requirements of the APT system on the positioning stability and high precision of the stepping motor.

Drawings

FIG. 1 is a schematic diagram of a system configuration according to an embodiment;

FIG. 2 is a schematic diagram of open-loop control of a stepping motor in an embodiment;

FIG. 3 is a schematic diagram of the closed-loop control of the stepping motor in the embodiment;

FIG. 4 is a schematic diagram of the control of the speed profile of the stepping motor in the embodiment;

FIG. 5 is a schematic flow chart of the method in the example.

Detailed Description

The invention will be further described with reference to the following drawings and examples, but the invention is not limited thereto.

Example (b):

referring to fig. 1, a motor control system of a wireless laser communication platform comprises a two-dimensional rotary table, wherein a processing controller, a horizontal stepping motor connected with the processing controller through a horizontal stepping motor driver, and a pitching stepping motor connected with the processing controller through a pitching stepping motor driver are arranged on the two-dimensional rotary table, the horizontal stepping motor and the pitching stepping motor are respectively connected with a horizontal magnetic encoder and a pitching magnetic encoder, the rotation angles of the horizontal stepping motor and the pitching stepping motor are respectively fed back to the processing controller through the horizontal magnetic encoder and the pitching magnetic encoder, the controller is used as a core, a dotted line in fig. 1 represents magnetic induction, the controller has the function of acquiring a target position, calculating the pulse number, driving the motor to move, receiving feedback information and controlling the motion mode of each process, the driver receives direction signals and pulse information to subdivide the driving motor, the magnetic encoder feeds back position information to the processing controller, and the two-dimensional rotary table is responsible for rotating.

In the embodiment, the horizontal stepping motor and the pitching stepping motor are both direct-current two-phase stepping motors and respectively control the horizontal shaft and the pitching shaft.

In this example, the horizontal stepping motor driver and the pitch stepping motor driver are 256 sub-divided drivers.

In this example, the horizontal magnetic encoder and the pitch magnetic encoder are both 4096-wire magnetic encoders.

As shown in fig. 5, a motor control method of a wireless laser communication platform includes a motor control system of the wireless laser communication platform, the method includes a control mode combining open-loop control and closed-loop feedback control to perform time-sharing control on a motor to achieve stable high-precision positioning, when a wireless laser communication APT system works, the system is divided into three stages of capturing, aligning and tracking, and different motor control strategies are respectively adopted for the three stages, wherein the capturing and aligning stages need to have a stable operation process and ensure sufficient torque, and at this time, a horizontal magnetic encoder and a pitching magnetic encoder do not need to feed back angle information, and can only use open-loop control, and the motor speed and the driving current are controlled according to the capturing and aligning conditions of the system to improve the operation stability and the torque, thereby ensuring the efficiency of capturing and aligning a target; and need higher positioning accuracy in the tracking stage to guarantee to establish reliable communication link, detect out-of-step and overshoot deviation through the code wheel, compensate the deviation that the motor out-of-step and overshoot produced, can improve the tracking accuracy of the motor, need to adopt closed-loop control, including the following steps:

1) Open-loop control: as shown in fig. 2, specifically, the following steps are performed:

1-1) firstly, when the motor is started, a control mode of large current and slow start is adopted to start the motor, so that high-torque and low-speed start is realized, and locked rotor and step-out are prevented from being generated during starting;

1-2) the controller of the scanning and capturing process controls the position, the speed and the current, in this case, the speed is set from 0 to t1 as an acceleration stage according to the speed curve shown in fig. 4, the speed is increased from 0 to the maximum value Vt, the speed is uniformly increased from 1 to 2, the speed is reduced from 2 to 3 from Vt to 0, the curve in fig. 4 is continuously smooth, has no abrupt change and no inflection point, and when the motor is accelerated or decelerated, the smooth operation in the scanning process due to step loss and overshoot is prevented; t1, t2, t3 and Vt are debugged and selected according to the actual running stability of the system;

1-3) when a target is captured to enter an alignment process, continuously converting the target position deviation into the number N (or the number of pulses) of steps required to be operated by the motor, sending the number N (or the number of pulses) to the motor for driving, and driving the motor to rotate to align the target;

2) Closed-loop feedback control, as shown in fig. 3, adopts three closed-loop control modes of current, speed and position, if the target does not move, the motor keeps static, the motor maintains torque with static load, if the target moves, the motor can rotate along with the target, the feedback values of the horizontal magnetic encoder and the pitching magnetic encoder are compared with the target position value, if the deviation value is greater than the precision error requirement value, the motor is controlled to rotate reversely to the target position, at the moment, the position deviation is calculated according to the position values fed back by the horizontal magnetic encoder and the pitching magnetic encoder to obtain a new operation step number N, meanwhile, the motor speed is reduced, system oscillation caused by continuous overshoot and backlash is prevented, the alignment state is continuously maintained, and continuous oscillation phenomenon is avoided.

Claims (5)

1. The utility model provides a motor control system of wireless laser communication platform, includes the two-dimensional revolving stage, its characterized in that, be equipped with processing controller on the two-dimensional revolving stage and pass through the horizontal step motor that horizontal step motor driver is connected and the every single move step motor who connects through every single move step motor driver with processing controller, horizontal step motor and every single move step motor connect horizontal magnetic encoder and every single move magnetic encoder respectively, horizontal step motor and every single move step motor's turned angle is fed back to processing controller by horizontal magnetic encoder and every single move magnetic encoder respectively.

2. The motor control system of claim 1, wherein the motor control system is configured to control the laser communication platform

The horizontal stepping motor and the pitching stepping motor are both direct-current two-phase stepping motors and respectively control a horizontal shaft and a pitching shaft.

3. The motor control system of the wireless laser communication platform of claim 1, wherein the horizontal stepping motor driver and the pitch stepping motor driver are 256-segment drivers.

4. The motor control system of the wireless laser communication platform as claimed in claim 1, wherein the horizontal magnetic encoder and the pitch magnetic encoder are 4096-wire magnetic encoders.

5. A motor control method of a wireless laser communication platform comprises the motor control system of the wireless laser communication platform as claimed in any one of claims 1 to 4, wherein the method comprises a control mode combining open-loop control and closed-loop feedback control to perform time-sharing control on a motor, and comprises the following steps:

1) Open-loop control: the method comprises the following specific steps:

1-1) firstly, when the motor is started, the motor is started by adopting a control mode of large current and slow start, so that the starting with large torque and low speed is realized, and the locked rotor and the step-out are prevented from being generated during the starting;

1-2) the controller of the scanning and capturing process controls the position, the speed and the current, the speed is set to be in an acceleration stage from 0 to t1, the speed is increased to the maximum value Vt from 0, the speed is in a uniform speed stage from 1 to 2, and the speed is reduced to 0 from Vt from 2 to 3, so that when the motor is accelerated or decelerated, the stable operation in the scanning process due to step loss and overshoot is prevented;

1-3) when a target is captured to enter an alignment process, continuously converting the target position deviation into the number N of steps required to be operated by the motor, sending the number N to the motor driver, and driving the motor to rotate to align the target;

2) Closed loop feedback control, adopt the three closed loop control mode of electric current, speed and position, if the target does not have the motion, the motor keeps static, the motor maintains the static moment of load, if the target has the motion, the motor can follow the rotation, compare horizontal magnetic encoder and every single move magnetic encoder feedback value and target position value this moment, if the deviation value is greater than precision error requirement value, control the motor and reverse to the target position, need calculate the position deviation according to the position value that horizontal magnetic encoder and every single move magnetic encoder feedback this moment and obtain new operation step number N, reduce motor speed simultaneously, prevent that continuous overshoot and backlash from causing system oscillation, make and continuously keep the alignment state, the shock phenomenon that can not appear continuously.

Images