Central control display screen based on three-axis control and control method

Abstract

The invention discloses a central control display screen based on three-axis control and a control method.The display screen comprises a Mai n MCU, a Motor MCU, a front-back three-axis motor, a left-right three-axis motor and an up-down three-axis motor, and the Mai n MCU and the Motor MCU communicate through Uart and are used for automatically controlling the front-back three-axis motor, the left-right three-axis motor and the up-down three-axis motor to move to target positions; wherein the Motor MCU controls and outputs three-phase current through six paths of PWM (Pulse Width Modulation) to control the motor to move, reads absolute angle information of a magnetic encoder through an SP I (Serial Peripheral Interface), and analyzes the absolute angle information into speed and feedback to control the three-phase current; in the vehicle driving process, through vehicle voice or touch operation, the angle can be automatically adjusted from the left-right dimension and the up-down dimension of the display screen, a comfortable operation angle is provided, and the user experience is improved; in a vehicle parking state, the display screen is prevented from being exposed to high temperature by controlling the vertical angle of the display screen, and the service life of the display screen is prolonged; by controlling the left and right angles, a welcome mode can be provided for a main driver during startup, and better user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of display screen control, and in particular to a central control display screen and a control method based on three-axis control. Background Art

[0002] As an important medium for human-computer interaction in the automotive field, the in-vehicle display screen is an important embodiment of the intelligentization of the automotive industry. Therefore, in-vehicle displays are becoming more and more popular among users. The central control display screen is an important medium for car computer control, and the central control display screen integrates the functions of the instrument display screen, such as displaying important information such as vehicle speed and fuel level, so users have higher and higher requirements for the central control screen.

[0003] At present, the installation position and angle of the central control display screen are fixed and cannot be moved. During driving, it is impossible to provide a better experience for the main driver and the front passenger. However, some models have a collapse structure on the central control display screen structure, and the display screen can be manually moved to a suitable position for intelligent operation, but manual control during vehicle movement poses certain risks to safe driving.

[0004] Since the display screen is installed at a fixed position and angle, direct sunlight causes the surface temperature of the display screen to be too high, which has a certain impact on the service life of the display screen. At the same time, due to the installation angle, the reflection is not conducive to the operation of the co-pilot user under direct sunlight, affecting the user experience. Summary of the invention

[0005] The main purpose of the present invention is to provide a central control display screen and a control method based on three-axis control, aiming to solve the existing technical problems.

[0006] To achieve the above object, the present invention provides a central control display screen based on three-axis control, the display screen includes a Main MCU, a Motor MCU and front and rear, left and right, and up and down three-axis motors, the Main MCU and the Motor MCU communicate with each other using Uart to automatically control the front and rear, left and right, and up and down three-axis motors to move to the target position;

[0007] The Motor MCU controls the motor movement by outputting three-phase current through 6-way PWM control, reads the absolute angle information of the magnetic encoder through the SPI interface, analyzes it into speed, and feedback controls the three-phase current.

[0008] Furthermore, the motor is controlled by FOC, and closed-loop control of the motor is performed through a current loop, a speed loop and a position loop.

[0009] Furthermore, the motor adopts a brushless DC motor with an absolute magnetic encoder, and the motor rotor position is fed back in real time by the magnetic encoder to calculate the mechanical angle of the motor movement. The angle and speed calculation method is as follows:

[0010] Real-time angle = 360 / (encoder accuracy * number of motor pole pairs) * number of real-time pulses;

[0011] Real-time speed = mechanical angle difference within time / time.

[0012] Furthermore, the position loop sampling in the Motor MCU is controlled by an S-shaped curve, and the motion position is calculated in real time according to the target angle and the target motion time, and the position information is converted into the number of magnetic encoder pulses, and a low-pass filtering operation is performed to convert it into the input of the speed loop;

[0013] The low-pass filtering operation of the position information is to put each position data into a queue, and the output of this filtering is the average value of all the sample values ​​in the queue minus a maximum value and a minimum value.

[0014] Furthermore, the Motor MCU performs PID control on the difference between the real-time speed feedback and the target speed output by the position loop, converts it into torque current as the input of the current loop, and adds forward speed feedback at the same time, specifically: forward speed feedback value = previous speed output by the position loop + current speed increment * 50%.

[0015] Furthermore, the Motor MCU performs PID control output on the difference between the output of the speed loop and the feedback current, and performs low-pass filtering operation at the same time to control the three-phase current of the motor movement in real time. The calculation formula of the low-pass filter is as follows:

[0016] y(n)=y(n-1)*kb+(x(n)+x(n-1))*ka

[0017] y(n-1): the last filtering output

[0018] x(n-1) / x(n): filter input

[0019] Kb / ka: Filter coefficient, confirmed based on simulation results.

[0020] A method for controlling a central control display screen, the method being applied to the central control display screen mentioned above, the method comprising:

[0021] When the display screen is turned on, the front and rear axis motors are first controlled to move to the specified position, and then the left and right, up and down angles are controlled to rotate;

[0022] To open the screen, first control the display screen to the specified position, then turn on the backlight and perform touch operation;

[0023] To turn off the screen, first reset the display screen to zero from the left and right and up and down dimensions, then control the front and rear axle motors to return to the default position and turn off the screen.

[0024] The beneficial effects of the present invention are embodied in:

[0025] In the present invention, during the driving of the vehicle, the angle of the display screen can be automatically adjusted from left to right and up to down through vehicle voice or touch operation, providing a comfortable operating angle and improving user experience;

[0026] When the vehicle is parked, the up and down angles of the display screen can be controlled to avoid high temperature exposure to the display screen and extend the service life of the display screen.

[0027] When the vehicle is driving, adjust the up and down angle of the display screen to avoid a bad user experience caused by reflections;

[0028] By controlling the left and right angles, a welcome mode can be provided for the main driver when the machine is turned on, thus providing a better user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The block diagram of the display screen based on three-axis control of the present invention;

[0030] Figure 2 This is the three-loop control block diagram of the motor of the present invention;

[0031] Figure 3 It is a schematic diagram of the S-shaped curve of the position loop sampling of the present invention;

[0032] Figure 4 The present invention is a flow chart of the switch screen motion control of the central control display screen based on three-axis control motion. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] See also Figure 1The present invention provides a central control display screen based on three-axis control, the display screen includes a Main MCU, a Motor MCU and front and rear, left and right, and up and down three-axis motors, the Main MCU and the Motor MCU communicate with each other using Uart to automatically control the front and rear, left and right, and up and down three-axis motors to move to a target position;

[0035] The Motor MCU controls the motor movement by outputting three-phase current through 6-way PWM control, reads the absolute angle information of the magnetic encoder through the SPI interface, analyzes it into speed, and feedback controls the three-phase current.

[0036] The control method of the present invention can achieve the effects of fast response, large torque and low noise.

[0037] Specifically, Main MCU has the following functions:

[0038] 1. Responsible for processing the vehicle CAN message, providing display screen network management, diagnostic services and motion interactive control functions;

[0039] 2. Provide correct power-on and power-off timing for deserializer MAX96772, LCD and other components, and ensure the effectiveness of the video link;

[0040] 3. The deserializer MAX96772 parses the GMSL2 video sent by the host into eDP signals and outputs them to the LCD for display;

[0041] 4. The LCD module provides an eDP video analysis module, as well as touch signal acquisition and data processing functions;

[0042] 5. The deserializer MAX96772 transmits the touch I2C signal to the host to avoid the degradation of touch performance;

[0043] 6. Communicate with Motor MCU through Uart to freely control the position of the display screen in three dimensions: front, back, left, right, and up and down.

[0044] Specifically, Motor MCU has the following functions:

[0045] 1. Parse Uart messages and automatically control the front, back, left, right, and up and down three-axis motors to move to the target position;

[0046] 2. Detect motor overcurrent, overtemperature, encoder, stall, finger clamping and other faults. If a fault is detected, stop the movement immediately.

[0047] During the driving process of the vehicle, the present invention can automatically adjust the angle of the display screen from left to right and up to down through vehicle voice or touch operation, providing a comfortable operating angle and improving user experience;

[0048] When the vehicle is parked, the up and down angles of the display screen can be controlled to avoid high temperature exposure to the display screen and extend the service life of the display screen.

[0049] When the vehicle is driving, adjust the up and down angle of the display screen to avoid a bad user experience caused by reflections;

[0050] By controlling the left and right angles, a welcome mode can be provided for the main driver when the machine is turned on, thus providing a better user experience.

[0051] In one embodiment, see Figure 2 The motor is controlled by FOC, and closed-loop control of the motor is performed through current loop, speed loop and position loop.

[0052] In one embodiment, the motor is a brushless DC motor with an absolute magnetic encoder. The magnetic encoder is used to feed back the motor rotor position in real time to calculate the mechanical angle of the motor movement. The angle and speed calculation method is as follows:

[0053] Real-time angle = 360 / (encoder accuracy * number of motor pole pairs) * number of real-time pulses; where the encoder accuracy is 16 bits, the corresponding value is 63536, and the number of motor pole pairs is related to the selected motor.

[0054] Real-time speed = mechanical angle difference within time / time. Among them, the current loop execution frequency is set to 20KHz, the speed execution frequency loop is set to 2kHz, and the position loop execution frequency is 1kHZ.

[0055] In one embodiment, see Figure 3 The position loop sampling in the Motor MCU is controlled by an S-shaped curve, and the motion position is calculated in real time according to the target angle and the target motion time. At the same time, the position information is converted into the number of magnetic encoder pulses, and a low-pass filtering operation is performed to convert it into the input of the speed loop;

[0056] The low-pass filtering operation of the position information is to put each position data into a queue, and the output of this filtering is the average value of all the sample values ​​in the queue minus a maximum value and a minimum value.

[0057] This position curve has the following advantages: continuous acceleration change, continuous speed change, small impact and smooth operation.

[0058] In one embodiment, the Motor MCU performs PID control on the difference between the real-time speed feedback and the target speed output by the position loop, converts it into torque current as the input of the current loop, and adds forward speed feedback at the same time, specifically: forward speed feedback value = previous speed output by the position loop + current speed increment * 50%.

[0059] In one embodiment, the Motor MCU performs PID control output on the difference between the output of the speed loop and the feedback current, and performs low-pass filtering operation at the same time to control the three-phase current of the motor movement in real time. The calculation formula of the low-pass filter is as follows:

[0060] y(n)=y(n-1)*kb+(x(n)+x(n-1))*ka

[0061] y(n-1): the last filtering output

[0062] x(n-1) / x(n): filter input

[0063] Kb / ka: Filter coefficient, confirmed based on simulation results.

[0064] The present invention also provides a control method for a central control display screen, see Figure 4 , the method is applied to the above-mentioned central control display screen, the method comprises:

[0065] When the display screen is turned on, the front and rear axis motors are first controlled to move to the specified position, and then the left and right, up and down angles are controlled to rotate;

[0066] To open the screen, first control the display screen to the specified position, then turn on the backlight and perform touch operation;

[0067] To turn off the screen, first reset the display screen to zero from the left and right and up and down dimensions, then control the front and rear axle motors to return to the default position and turn off the screen.

[0068] Specifically, the front and rear axle motors only have two movement positions: 0° and 30°. The specific target position should be confirmed according to the actual project.

[0069] The left and right motors can move at angles between -1000° and 100°, and the up and down motors can move at any angle between -60° and 60°, with an accuracy of 1°;

[0070] The zero position of the left and right and up and down dimensions is exactly in the middle, that is, (0°, 0°).

[0071] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, back, etc., then the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture as shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly.

[0072] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A central control display screen based on three-axis control, characterized in that: The display screen includes a Main MCU, a Motor MCU, and three-axis motors for front and back, left and right, and up and down. The Main MCU and the Motor MCU communicate with each other using Uart to automatically control the three-axis motors for front and back, left and right, and up and down to move to a target position. The Motor MCU controls the motor movement by outputting three-phase current through 6-way PWM control, reads the absolute angle information of the magnetic encoder through the SPI interface, analyzes it into speed, and feedback controls the three-phase current.

2. A central control display screen based on three-axis control as claimed in claim 1, characterized in that: The motor is controlled by FOC, and closed-loop control is performed on the motor through a current loop, a speed loop and a position loop.

3. The central control display screen based on three-axis control according to claim 1, characterized in that: The motor adopts a brushless DC motor with an absolute magnetic encoder. The magnetic encoder is used to feed back the motor rotor position in real time to calculate the mechanical angle of the motor movement. The angle and speed calculation method is as follows: Real-time angle = 360 / (encoder accuracy * number of motor pole pairs) * number of real-time pulses; Real-time speed = mechanical angle difference within time / time.

4. The central control display screen based on three-axis control according to claim 1, characterized in that: The position loop sampling in the Motor MCU is controlled by an S-shaped curve, and the motion position is calculated in real time according to the target angle and the target motion time. At the same time, the position information is converted into the number of magnetic encoder pulses, and a low-pass filtering operation is performed to convert it into the input of the speed loop; The low-pass filtering operation of the position information is to put each position data into a queue, and the output of this filtering is the average value of all the sample values ​​in the queue minus a maximum value and a minimum value.

5. The central control display screen based on three-axis control according to claim 1, characterized in that: The Motor MCU performs PID control on the difference between the real-time speed feedback and the target speed output by the position loop, converts it into torque current as the input of the current loop, and adds forward speed feedback at the same time, specifically: forward speed feedback value = previous speed output by the position loop + current speed increment * 50%.

6. The central control display screen based on three-axis control according to claim 1, characterized in that: In the Motor MCU, the difference between the output of the speed loop and the feedback current is output through PID control, and a low-pass filter is performed at the same time to control the three-phase current of the motor movement in real time. The calculation formula of the low-pass filter is as follows: y(n)=y(n-1)*kb+(x(n)+x(n-1))*ka y(n-1): the last filtering output x(n-1) / x(n): filter input Kb / ka: Filter coefficient, confirmed based on simulation results.

7. A method for controlling a central control display screen, characterized in that: The method is applied to the central control display screen according to any one of claims 1 to 6, and the method comprises: When the display screen is turned on, the front and rear axis motors are first controlled to move to the specified position, and then the left and right, up and down angles are controlled to rotate; To open the screen, first control the display screen to the specified position, then turn on the backlight and perform touch operation; To turn off the screen, first reset the display screen to zero from the left and right and up and down dimensions, then control the front and rear axle motors to return to the default position and turn off the screen.

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