Nanosecond laser cleaning method and system based on ARM architecture

Abstract

The invention relates to a nanosecond laser cleaning method and system based on an ARM architecture, in particular to a laser cleaning control method for high-capacity rapid storage and data multiplexing. According to the method, the laser cleaning process is optimized by integrating a high-capacity rapid storage technology and a data multiplexing strategy. The system adopts an SDRAM (Synchronous Dynamic Random Access Memory) to store and record a laser scanning path, and integrates a Cache mechanism to reduce data calling delay and improve the response speed of the system. By combining the position modulation laser frequency technology, the scanning period is finely adjusted, edge erosion caused by motor deceleration is avoided, and the uniformity and accuracy of laser cleaning are ensured. The invention further provides a dynamic phase difference spiral algorithm, the laser cleaning efficiency is remarkably improved, and the calculation burden of repeated tasks is reduced. Experimental results show that the speed and data filling efficiency of the method are superior to those of a linear filling algorithm under the same output point condition, excessive erosion can be effectively prevented, and the overall efficiency and performance of laser cleaning operation are comprehensively improved.

Description

Technical Field

[0001] The present invention relates to the field of laser cleaning technology, in particular to a nanosecond laser cleaning method and system based on an ARM architecture, which are used for laser cleaning control with high-capacity fast storage and data multiplexing. Background Art

[0002] Since its introduction in 1969, laser cleaning technology has become a research hotspot in industrial manufacturing due to its non-contact, high-precision, and low-pollution advantages. However, existing laser cleaning technologies are inefficient when handling repetitive tasks, and system deployment and maintenance costs are high. Traditional laser cleaning systems often use FPGA control. While this offers flexibility and parallelism, the high computational latency and resource consumption during continuous, high-speed cleaning processes significantly reduce cleaning efficiency. Summary of the Invention

[0003] The purpose of the present invention is to provide a nanosecond laser cleaning method and system based on ARM architecture, which optimizes the laser cleaning process and improves the cleaning efficiency and system response speed by integrating high-capacity fast storage technology and data multiplexing strategy.

[0004] The main technical solutions of the present invention are as follows:

[0005] Laser cleaning system architecture: The system includes an ARM control system, a 1064nm laser, a digital galvanometer, and a field lens. The ARM control system communicates with the host computer via the command communication module, parses the custom RS232 protocol, and passes the generated tasks to the algorithm control module. After the algorithm control module generates the laser path, it stores it in the cache high-speed storage module. Finally, the laser cleaning system receives the task through the command communication module and passes it to the XY2-100 protocol output module, ultimately forming a laser spot under the focus of the field lens.

[0006] Cache mechanism: The system introduces a cache mechanism based on the STM32H7 series MCU and SDRAM, significantly reducing the computational cost of repeated cleaning tasks and improving real-time computing efficiency. By properly configuring the cache strategy and size, the number of CPU accesses to SDRAM is reduced, reducing system latency.

[0007] Dynamic Phase Difference Spiral Algorithm: This algorithm improves laser cleaning speed by synchronously controlling the X / Y galvanometer motors to maintain deflection and avoid excessive reverse acceleration. The algorithm dynamically adjusts the phase difference between the two channel curves to generate complementary images, ensuring complete coverage of the target cleaning area.

[0008] The mathematical expression of the dynamic phase difference spiral algorithm is:

[0009] channelX=RowWidth*sin(p*θ)

[0010] channelY=ColumeWidth*sin(q*8+PhaseOffset)

[0011] Among them, the X / Y galvanometer motor group path is mainly generated separately by the dynamic phase difference spiral algorithm. The X galvanometer motor control signal (channelX) and the Y galvanometer motor control signal (channelY) first generate a basic image with p horizontal sub-lobes, q vertical sub-lobes, row width of RowWidth, and column width of VolumeWidth according to the Lissajous curve. Then, the phase difference (PhaseOffset) of the dual-channel curve is dynamically adjusted, and supplementary images are continuously generated to ensure complete coverage of the target cleaning area.

[0012] Among them, in order to prevent excessive edge cleaning due to reverse acceleration during cleaning, the system combines the dynamic phase difference spiral algorithm described in claim 1 to reduce the laser frequency in the process of approaching the edge. When any channel approaches the peak, it is determined to be close to the edge area. At this time, the laser frequency is linearly reduced, and the laser frequency is linearly increased after leaving the edge area. The laser generator does not need to be turned off during the whole process, and the main oscillator in the laser generator is always in an excited state.

[0013] System Design: Built using the Keil ARM-MDK5 compiler, the system consists of an algorithm control module, an XY2-100 protocol output module, a cache high-speed storage module, and a command communication module. The algorithm control module generates the laser path, the XY2-100 protocol output module sends control signals via a timer interrupt GPIO package, the cache high-speed storage module stores the laser path, and the command communication module receives commands from the host computer via RS232. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the architecture diagram of the laser cleaning system;

[0015] Figure 2 Analytical diagram of the access process of the Cache high-speed reading mechanism;

[0016] Figure 3 This is the effect diagram of the running process of the dynamic phase difference spiral algorithm;

[0017] Figure 4 This is the control timing diagram of the laser frequency changing with the cleaning path;

[0018] Figure 5a This is the front of the ARM system development board;

[0019] Figure 5bThis is the back of the ARM system development board; DETAILED DESCRIPTION

[0020] See also Figures 1 to 5b As shown, the specific embodiments of the present invention are now described in detail as follows:

[0021] The present invention mainly targets the laser cleaning system, and considers the problems of uneven cleaning and over-ablation of edges encountered during actual construction. It proposes an ARM architecture control board for a nanosecond laser cleaning method and system and a dynamic phase difference spiral algorithm adapted to actual construction.

[0022] Figure 1 The laser cleaning system architecture uses an ARM control system. The command communication module communicates with the host computer, parses the RS232 custom protocol, and passes the generated tasks to the algorithm control module. After the algorithm control module generates the laser path, it stores it in the cache high-speed storage module. Finally, the laser cleaning system receives the task through the command communication module and passes it to the XY2-100 protocol output module, ultimately forming a laser spot under the focus of the field lens.

[0023] Figure 2 The cache mechanism used in this system, based on the STM32H7 series MCU and SDRAM, significantly reduces the computational cost of repeated cleaning tasks and improves real-time computing efficiency. By properly configuring the cache strategy and size, the number of CPU accesses to SDRAM is reduced, reducing system latency.

[0024] Figure 3 This image shows the dynamic phase-difference spiral algorithm in action: This invention proposes a dynamic phase-difference spiral algorithm that synchronously controls the X / Y galvanometer motors to maintain deflection and avoid excessive reverse acceleration, thereby increasing laser cleaning speed. The algorithm dynamically adjusts the phase difference between the two channel curves to generate complementary images, ensuring complete coverage of the target cleaning area.

[0025] Figure 4 In order to prevent excessive edge cleaning due to reverse acceleration during cleaning, this system combines the dynamic phase difference spiral algorithm described in claim 1 to reduce the laser frequency during the process of approaching the edge. When any channel approaches the peak, it is determined to be close to the edge area. At this time, the laser frequency is linearly reduced, and the laser frequency is linearly increased after leaving the edge area. The laser generator does not need to be turned off during the whole process, and the main oscillator in the laser generator is always in an excited state.

[0026] Figure 5a and Figure 5bDesigned for the ARM system development board: stepper motor interfaces 1, 2, 3; encoder interface 4; galvanometer motor control interface 5; laser generator control interface 6; power supply interface 7; 24V signal trigger interface 8; 24V signal output interface 9; CAN communication interface 10; RS485 communication interface 11; RS232 communication interface 12; OTA upgrade serial port 13; program download port 14.

Claims

1. A nanosecond laser cleaning method and system based on ARM architecture, characterized in that: The following steps are involved: (1) Using SDRAM to store and record the laser scanning path: (2) Integrate a cache mechanism to reduce data call delays and improve system response speed: (3) Combined with position-modulated laser frequency technology, the scanning cycle is finely adjusted to avoid edge erosion caused by motor deceleration; (4) The dynamic phase difference spiral algorithm is used to generate the laser cleaning path, which significantly improves the cleaning efficiency.

2. The system includes an ARM control system, a 1064nm laser, a digital galvanometer and a field mirror, and communicates with the host computer via RS232 to generate XY2-100 digital galvanometer control signals and laser generator control signals.

3. The nanosecond laser cleaning method and system according to claim 1, characterized in that: The dynamic phase difference spiral algorithm improves the laser cleaning speed by synchronously controlling the X / Y galvanometer motors to maintain deflection and avoid excessive reverse acceleration. Among them, when cleaning the edge, the reverse acceleration may cause excessive edge cleaning. This system combines the dynamic phase difference spiral algorithm described in claim 1 to reduce the laser frequency in the process of approaching the edge. When any channel approaches the peak, it is determined to be close to the edge area. At this time, the laser frequency is linearly reduced, and the laser frequency is linearly increased after leaving the edge area. The laser generator does not need to be turned off during the whole process, and the main oscillator in the laser generator is always in an excited state.

4. The nanosecond laser cleaning method and system according to claim 1, characterized in that: The cache mechanism includes D-Cache and I-Cache, which are used to optimize the access process of repeated instructions, reduce the number of times the CPU accesses SDRAM, and reduce system latency.

5. The nanosecond laser cleaning method and system according to claim 1, characterized in that: The laser cleaning system implements embedded control through the STM32H7 series MCU, reducing development difficulty and hardware costs.

6. The nanosecond laser cleaning method and system according to claim 1, characterized in that: The laser cleaning system generates a laser path through a dynamic phase difference spiral algorithm and sends a control signal through an XY2-100 protocol output module to control the digital galvanometer motor and the laser generator. The mathematical expression of the dynamic phase difference spiral algorithm is: channelX=RowWidth*sin(p*θ) channelY=ColumeWidth*sin(q*θ+PhaseOffset) Among them, the X / Y galvanometer motor group path is mainly generated separately by the dynamic phase difference spiral algorithm. The X galvanometer motor control signal (channelX) and the Y galvanometer motor control signal (channelY) first generate a basic image with p horizontal sub-lobes, q vertical sub-lobes, row width of RowWidth, and column width of VolumeWidth according to the Lissajous curve. Then, the phase difference (PhaseOffset) of the dual-channel curve is dynamically adjusted, and supplementary images are continuously generated to ensure complete coverage of the target cleaning area.

7. The nanosecond laser cleaning method and system according to claim 1, characterized in that: The laser cleaning system stores the laser path through the Cache high-speed storage module and receives host computer instructions through the instruction communication module to control the generation and execution of the laser cleaning task.

Images