Anti-impact method and device for stabilized platform based on micromechanical gyroscope

Abstract

The invention discloses an impact resistance method and device for a stabilized platform based on a micromechanical gyroscope, and the method comprises the steps: recording the angle amount of the stabilized platform which is not operated due to a control bandwidth when the stabilized platform is subjected to impact or high-frequency vibration by adopting a gyroscope integration method, and continuously compensating the angle amount to a control system. The problem of pointing angle deviation caused by transient impact or high-frequency vibration can be effectively solved. The invention relates to the technical field of platform design. According to the impact resistance method and device for the stabilized platform based on the micromechanical gyroscope, the acceleration of the environment where the stabilized platform is located is calculated through a gyroscope differential method, and the acceleration is used for judging the stability of the platform environment and serves as a threshold value for starting integration of gyroscope data; a solution is given under the condition that the stable holder in a continuous tracking state is subjected to external impact, the pointing of a system can be kept stable for small-order impact, and the stable holder can still point to a target after being impacted for large-order impact.

Description

Technical Field

[0001] The present invention relates to the technical field of platform design, and in particular to a method and device for resisting shock of a stable platform based on a micro-mechanical gyroscope. Background Art

[0002] Traditional stabilization platform designs use velocity parameters in an inertial coordinate system, detected by gyroscopes, to close the platform's velocity loop, eliminating carrier jitter and stabilizing the load's spatial orientation. The platform's stability accuracy is generally affected by parameters such as the closed-loop bandwidth of the servo control loop and the closed-loop frequency and accuracy of the gyroscopes.

[0003] When a stabilizing platform's carrier is subjected to an external impact, the load's spatial orientation on the platform will experience angular displacement. This is primarily due to two reasons: 1) The frequency of the stabilizing platform's carrier motion upon impact is much greater than the closed-loop frequency of the control platform, resulting in angular positional displacement due to the control platform's motion lag; and 2) The center of mass of the load on the stabilizing platform is not at the center of rotation. The unbalanced torque applied at the moment of impact causes the load on the stabilizing platform to rotate about the center of rotation, resulting in angular positional displacement.

[0004] There are two common methods for stable platform control technology to deal with external impact on the carrier:

[0005] The first method relies on the current loop's rapid response to the current generated by the motor's rotation, maintaining stability at the set current. This approach has some effect on the effects of unbalanced load torque (cause 2 of angular offset mentioned above), but it does not improve the effects of platform motion lag (cause 1).

[0006] The second method uses an attitude sensor mounted on the carrier to inversely calculate the pointing angle of the stabilized platform after an impact. This approach significantly increases system complexity, and the frequency and accuracy of attitude information returned by typical attitude sensors fall far short of the closed-loop requirements of the motor control loop, resulting in poor pointing accuracy and ineffective performance.

[0007] Existing stabilization platform impact resistance technology cannot address the problem of angular displacement of the load's spatial pointing direction caused by the carrier's high-frequency vibration at the moment of impact. This is especially true when the stabilization platform is tracking a target. Because the tracking closed-loop frequency is limited by the image frame rate and tracking algorithm latency, it is generally below 100Hz. Some industrial cameras even have a tracking closed-loop frequency of only 30Hz. In this case, if the load's angular position shifts at the moment of impact, it can easily cause target tracking to be lost, forcing the stabilization platform system to stop working.

[0008] In addition, the stable platform of the prior art cannot quickly recover the original pointing angle after the load angle shifts. The reason is that after the impact ends, the attitude of the carrier has changed significantly, and the spatial direction targeted by the original platform pointing angle is completely different from that before the impact. If the carrier attitude information is substituted and a new platform pointing angle is recalculated, the calculation time used in this process is long, the sensor accuracy is low, and the complexity of the system increases greatly.

[0009] Term Explanation:

[0010] Carrier: A device that carries a stable platform, such as a vehicle, aircraft, ship, etc.

[0011] Stable platform: A rotating pan-tilt with two-axis or three-axis systems such as azimuth and pitch, containing gyro sensors, which can stably point to a certain spatial angle.

[0012] Load: A hypothetical device on the stable platform, such as: optoelectronic payload (visible light camera, infrared thermal imager, etc.), radar payload, etc. Summary of the Invention

[0013] (1) Technical problems to be solved

[0014] In view of the deficiencies of the prior art, the present invention provides a method and device for a stable platform to resist impact based on a microelectromechanical gyro. Based on the microelectromechanical gyro sensor, the impact resistance of the stable platform is solved. Different from the original design, starting from the speed loop and position loop of the platform control, the load pointing smoothness is improved when the load on the stable platform is impacted, and the load can still continuously point to the target after the impact ends, so that the system can continuously and stably track the target under the impact that can be tolerated, and can still re-capture the target after a large impact ends. Moreover, during the impact resistance process of the stable platform device of the present invention, without relying on the attitude information of the carrier, it can be realized only by its own microelectromechanical gyro. The implementation method is convenient, has a wide applicability, and does not require changing the system hardware.

[0015] (2) Technical solutions

[0016] To achieve the above objectives, the present invention is realized through the following technical solutions: A method for a stable platform to resist impact based on a microelectromechanical gyro, comprising the following steps:

[0017] S1. Use a microelectromechanical gyro sensor to collect the platform rotation speed value v and perform sensor speed caching;

[0018] S2. Retain the previous frame cache value according to the acceleration and enter the impact resistance integration state to obtain the gyro integration angle value α, and then the current position of the position loop of the servo control system is β, and the target position is β + α;

[0019] S3. Use the position information obtained by integrating the gyro sensor in step S2 as the position target quantity, send it into the incremental position loop PID algorithm to obtain the target speed, and then close the loop through the speed loop PID algorithm. When the carrier is impacted, the stable platform realizes the coordinated response of the current loop, speed loop, and position loop to achieve the anti-impact effect, thereby driving the stable platform to rotate.

[0020] Preferably, in step S1, the collected speed value v is differentiated to calculate the acceleration a, and then it is judged whether the acceleration a is greater than the threshold b. If it is greater than the threshold b, the sensor speed is cached.

[0021] Preferably, in step S3, the rotation speed of the gyro-sensitive stable platform and the attitude speed of the carrier are cached through the sensor speed, and are transmitted to step S2 to continue calculating the gyro integration angle value α.

[0022] Preferably, the closed-loop bandwidth of the speed loop in step S3 is 20 - 30Hz.

[0023] The present invention also provides a stable platform anti-impact device based on a micro-machined gyroscope, which adopts the stable platform anti-impact method based on a micro-machined gyroscope, including a visible light camera, an infrared camera, an azimuth and elevation two-axis frame platform, a motor, an angular displacement sensor, a gyro sensor, and a control circuit board.

[0024] Preferably, the response frequency of the gyro sensor is 400Hz, and the data transmission frequency is 2000Hz, and its performance is higher than the speed loop response ability of the stable platform.

[0025] Preferably, in the control part, the above strategy is adopted to basically save the unexecuted speed quantity for subsequent execution compensation to ensure the correctness of the load pointing.

[0026] Preferably, the motor parameters are: peak stall torque: ≥ 0.06 Nm, peak stall current: 1.6 A ± 10%, peak stall voltage: 12 VDC ± 10%, maximum no-load speed: 2700 RPM ± 10%, continuous stall torque: ≥ 0.038 Nm, continuous stall current: 1 A ± 10%, number of pole pairs: 8.

[0027] Preferably, the angular displacement sensor parameters are: resistance value: 2 ± 0.2 kΩ, effective electrical stroke: 120 ± 3°, mechanical stroke: 360°, independent linearity: ± 1%, return accuracy: 0.1°, starting torque: ≤ 3 mN·m.

[0028] Preferably, the parameters of the gyro sensor are as follows: measuring range: ±450° / s, zero bias over full temperature range: -150 to +150° / s, zero bias instability: ≤3° / h, zero bias repeatability: ≤15° / h, bandwidth: ≥400Hz, refresh rate: 2000Hz.

[0029] (III) Advantageous Effects

[0030] The present invention provides a method and device for shock resistance of a stabilization platform based on a micro-machined gyroscope. Compared with the prior art, the following advantageous effects are achieved:

[0031] (1) For the method and device for shock resistance of a stabilization platform based on a micro-machined gyroscope, by using the method of gyro integration to record the angular amount that the stabilization platform does not operate due to the control bandwidth when being impacted or experiencing high-frequency vibration, and continuously compensating it to the control system, the problem of pointing angle deviation caused by transient shock or high-frequency vibration can be effectively eliminated.

[0032] (2) For the method and device for shock resistance of a stabilization platform based on a micro-machined gyroscope, by using the method of gyro differentiation to calculate the acceleration amount of the environment where the stabilization platform is located, it is used to judge the stability of the platform environment and serve as the threshold for starting gyro data integration.

[0033] (3) For the method and device for shock resistance of a stabilization platform based on a micro-machined gyroscope, by giving a solution for the continuously tracked stabilization platform when it is impacted externally. For small-scale impacts, the pointing of the system can be kept stable, and for large-scale impacts, the stabilization platform can still point to the target after the impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is the execution flow chart of the stabilization platform device of the present invention;

[0035] Figure 2 is the block diagram of the composition of the stabilization platform device of the present invention;

[0036] Figure 3 is the structural design drawing of the stabilization platform device of the present invention;

[0037] Figure 4 is the first experimental data curve graph without using the stabilization platform device of the present invention;

[0038] Figure 5 is the second experimental data curve graph without using the stabilization platform device of the present invention;

[0039] Figure 6 is the first experimental data curve graph using the stabilization platform device of the present invention;

[0040] Figure 7 is the second experimental data curve graph using the stabilization platform device of the present invention. Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] Please refer to Figure 1-7 , the embodiments of the present invention provide two technical solutions: a method and device for shock resistance of a stable platform based on a micro-machined gyroscope, specifically including the following embodiments:

[0043] Embodiment 1: A method for shock resistance of a stable platform based on a micro-machined gyroscope, including the following steps:

[0044] S1. Use a micro-machined gyroscope sensor to collect the platform rotation speed value v and perform sensor speed caching;

[0045] S2. Retain the previous frame cache value according to the acceleration and enter the shock resistance integration state to obtain the gyro integration angle value α. Then, through the servo control system, the current position of the position loop is β, and the target position is β + α;

[0046] S3. Use the position information obtained by integrating the gyro sensor in step S2 as the position target quantity, send it to the incremental position loop PID algorithm to obtain the target speed, and then close the loop through the speed loop PID algorithm. When the carrier is impacted, the stable platform responds synergistically from the current loop, speed loop, and position loop to achieve the shock resistance effect, thereby driving the stable platform to rotate.

[0047] In the embodiment of the present invention, in step S1, the collected speed value v is differentiated to calculate the acceleration a, and then it is judged whether the acceleration a is greater than the threshold b. If it is greater than the threshold b, the sensor speed caching is performed.

[0048] In the embodiment of the present invention, in step S3, the gyro senses the rotation speed of the stable platform and the attitude speed of the carrier through sensor speed caching, and transmits them to step S2 to continue calculating the gyro integration angle value α.

[0049] The embodiment of the present invention also provides a device for shock resistance of a stable platform based on a micro-machined gyroscope, which adopts the method for shock resistance of a stable platform based on a micro-machined gyroscope, and includes a visible light camera, an infrared camera, an azimuth and elevation two-axis frame platform, a motor, an angular displacement sensor, a gyro sensor, and a control circuit board.

[0050] In an embodiment of the present invention, the response frequency of the gyro sensor is 400 Hz, and the data transmission frequency is 2000 Hz. Its performance is higher than the speed loop response ability of the stable platform. The above strategy is adopted in the control part to basically save the unexecuted speed quantity for subsequent execution compensation to ensure the correctness of the load pointing. The parameters of the gyro sensor are: range: ±450° / s, full-temperature zero offset: -150 to +150° / s, zero-offset instability: ≤3° / h, zero-offset repeatability: ≤15° / h, bandwidth: ≥400 Hz, refresh rate: 2000 Hz.

[0051] Embodiment 2: A method for a stable platform based on a micromachined gyroscope to resist impact, comprising the following steps:

[0052] S1. Use a micromachined gyro sensor to collect the platform rotation speed value v for sensor speed caching;

[0053] S2. Retain the previous frame cache value according to the acceleration and enter the anti-impact integration state to obtain the gyro integrated angle value α. Then, through the servo control system, the current position of the position loop is β, and the target position is β + α;

[0054] S3. Take the position information obtained by integrating the gyro sensor in step S2 as the position target quantity, send it to the incremental position loop PID algorithm to obtain the target speed, and then close the loop through the speed loop PID algorithm. When the carrier is impacted, the stable platform responds synergistically from the current loop, speed loop, and position loop to achieve the anti-impact effect, thereby driving the stable platform to rotate.

[0055] In an embodiment of the present invention, in step S1, the collected speed value v is differentiated to calculate the acceleration a, and then it is judged whether the acceleration a is greater than the threshold b. If it is greater than the threshold b, the sensor speed is cached.

[0056] In an embodiment of the present invention, in step S3, the gyro senses the rotation speed of the stable platform and the attitude speed of the carrier through sensor speed caching. And it is transmitted to step S2 to continue calculating the gyro integrated angle value α. The closed-loop bandwidth of the speed loop is 20 - 30 Hz.

[0057] An embodiment of the present invention also provides a device for a stable platform based on a micromachined gyroscope to resist impact, which adopts the method for a stable platform based on a micromachined gyroscope to resist impact, and includes a visible light camera, an infrared camera, an azimuth and elevation two-axis frame platform, a motor, an angular displacement sensor, a gyro sensor, and a control circuit board.

[0058] In an embodiment of the present invention, the response frequency of the gyro sensor is 400 Hz, and the data transmission frequency is 2000 Hz. Its performance is higher than the speed loop response ability of the stable platform. By adopting the above strategy in the control part, the unexecuted speed quantity is basically saved for subsequent execution compensation to ensure the correctness of the load pointing. The parameters of the gyro sensor are as follows: measuring range: ±450° / s, full-temperature zero bias: -150 to +150° / s, zero bias instability: ≤3° / h, zero bias repeatability: ≤15° / h, bandwidth: ≥400 Hz, refresh rate: 2000 Hz.

[0059] In an embodiment of the present invention, the parameters of the motor are as follows: peak stall torque: ≮0.06 Nm, peak stall current: 1.6 A ± 10%, peak stall voltage: 12 VDC ± 10%, maximum no-load speed: 2700 RPM ± 10%, continuous stall torque: ≮0.038 Nm, continuous stall current: 1 A ± 10%, number of pole pairs: 8.

[0060] In an embodiment of the present invention, the parameters of the angular displacement sensor are as follows: resistance value: 2 ± 0.2 kΩ, effective electrical travel: 120 ± 3°, mechanical travel: 360°, independent linearity: ±1%, return accuracy: 0.1°, starting torque: ≤3 mN.m.

[0061] Perform a 150 g / 10 ms shock test on the stable platform device, and compare the device using this method with the device not using this method. For the stable cloud platform device not using this method in the data situation, the experimental data curve is as shown in Figure 4 and Figure 5 For the stable cloud platform device using this method, the experimental data curve is as shown in Figure 6 and Figure 7 As can be seen from the experimental data curve, when the stable cloud platform device using this method is subjected to a 150 g / 10 ms shock, the platform response is stable. After the shock, the platform can immediately return to the original angular position and continuously point to the target. On the contrary, the stable cloud platform device not using this method generates large oscillations after being shocked, immediately deviates from the original pointing angle, and cannot return to the original position after the shock ends.

[0062] In summary, the present invention records the angular amount that the stable platform does not operate due to the control bandwidth when it is subjected to impacts or high-frequency vibrations by using the gyro integration method, and continuously compensates it to the control system. It can effectively eliminate the pointing angle deviation problem caused by transient impacts or high-frequency vibrations. By using the gyro differentiation method, the acceleration amount of the environment where the stable platform is located is calculated, which is used to judge the stability of the platform environment and serves as the threshold for starting the integration of gyro data. A solution is given for the continuously tracked stable pan-tilt when it is subjected to external impacts. For small-scale impacts, the pointing of the system can be kept stable, and for large-scale impacts, the stable platform can still point to the target after the impact.

[0063] Meanwhile, the content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0064] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0065] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A shock-resistant method for a stabilized platform based on a micro-machined gyroscope, characterized in that: It includes the following steps: S1. Use a micro-machined gyro sensor to collect the rotational speed value v of the platform and perform sensor speed caching; S2. Retain the previous frame cache value according to the acceleration and enter the anti-shock integration state to obtain the gyro integrated angle value α. Then, the current position of the position loop of the servo control system is β, and the target position is β + α; S3. Take the position information obtained by integrating the gyro sensor in step S2 as the position target quantity, send it to the incremental position loop PID algorithm to obtain the target speed, and then close the loop through the speed loop PID algorithm. When the carrier is impacted, the stable platform can achieve coordinated response from the current loop, speed loop, and position loop to achieve the anti-shock effect, thereby driving the stable platform to rotate.

2. A shock-resistant method for a stabilized platform based on a micromachined gyroscope according to claim 1, characterized in that: In step S1, the collected speed value v is differentiated to calculate the acceleration a, and then it is judged whether the acceleration a is greater than the threshold b. If it is greater than the threshold b, sensor speed caching is performed.

3. A shock-resistant method for a stable platform based on a micromachined gyroscope according to claim 1, characterized in that: In step S3, the gyro senses the rotational speed of the stable platform and the attitude speed of the carrier through sensor speed caching, and transmits them to step S2 to continue calculating the gyro integrated angle value α.

4. A shock-resistant method for a stable platform based on a micromachined gyroscope according to claim 1, characterized in that: In step S3, the closed-loop bandwidth of the speed loop is 20 - 30Hz.

5. A shock-resistant device for a stabilized platform based on a micromachined gyroscope, which adopts the shock-resistant method for a stabilized platform based on a micromachined gyroscope described in any one of claims 1-4, and is characterized in that: It includes a visible light camera, an infrared camera, an azimuth and elevation two-axis frame platform, a motor, an angular displacement sensor, a gyro sensor, and a control circuit board.

6. The anti-shock device for a stabilized platform based on a micromachined gyro according to claim 5, wherein: The response frequency of the gyro sensor is 400Hz, and the data transmission frequency is 2000Hz, and its performance is higher than the speed loop response ability of the stable platform.

7. An anti-shock device for a stabilized platform based on a micromachined gyroscope according to claim 6, characterized in that: In the control part, the above strategy is adopted to basically save the unexecuted speed quantity for subsequent execution compensation to ensure the correctness of the load pointing.

8. A shock-resistant device for a stabilized platform based on a micromachined gyroscope according to claim 5, characterized in that: The parameters of the motor are: peak stall torque: ≮0.06 Nm, peak stall current: 1.6 A ± 10%, peak stall voltage: 12 VDC ± 10%, maximum no-load speed: 2700 RPM ± 10%, continuous stall torque: ≮0.038 Nm, continuous stall current: 1 A ± 10%, number of pole pairs:

8.

9. A shock-resistant device for a stable platform based on a micromachined gyroscope according to claim 5, characterized in that: The parameters of the angular displacement sensor are: resistance value: 2 ± 0.2 kΩ, effective electrical stroke: 120 ± 3°, mechanical stroke: 360°, independent linearity: ±1%, return position accuracy: 0.1°, starting torque: ≤3 mN.m.

10. A shock-resistant device for a stable platform based on a micromachined gyroscope according to claim 5, characterized in that: The parameters of the gyro sensor are: range: ±450° / s, full-temperature zero bias: -150~+150° / s, zero bias instability: ≤3° / h, zero bias repeatability: ≤15° / h, bandwidth: ≥400Hz, refresh rate: 2000Hz.

Images