Bai Peiji, Shenzhen Zhongweixing CNC Technology Co., Ltd. Abstract: This paper introduces the implementation scheme of a spray painting machine control system using the DOS operating system. The system uses the Adt-TP104 motion controller, which adopts an industrial-grade 586 motherboard, equipped with an Adt836 motion control card, and a 10.4-inch LCD screen for touch operation. During processing, it can display processing information and fault prompts in real time. Keywords: Adt836 motion control card, Adt-TP104 controller, spray painting machine control system 1 Introduction In recent years, with the widespread application of electronic technology, especially electronic computers, the research and development and production of CNC systems for industrial automation control has become a rapidly developing emerging technology in the high-tech field. Its development organically combines mechanization and automation. In response to the special needs of the current coating industry, the production mode previously dominated by manual spraying has gradually transformed into automatic spraying. Automatic spraying has the characteristics of continuous repetitive work and labor, fatigue-free operation, and no fear of danger. Therefore, this automatic spraying mode has received attention from many industries and is being applied more and more widely. To address the characteristics of automated spraying and achieve digital control, a low-level control system based on an industrial computer and the Adt836 motion control card was developed. This integrated motion control card simplifies the hardware circuit structure of the entire control system and improves its reliability and control accuracy. 2. System Composition The system mainly consists of an Adt-TP104 controller, auxiliary wiring terminals, and a spraying machine software control system developed based on DOS. The controller incorporates the Adt836 motion control card, developed by Shenzhen Zhongweixing CNC Technology Co., Ltd., based on the PC104 bus. [IMG=Fig. 1]/uploadpic/THESIS/2007/11/2007111311264276860T.jpg[/IMG] Fig. 1 The high-performance six-axis servo/stepper control card in Fig. 1 has a variable position ring, allowing for speed changes during movement, and features linear, circular, and continuous differential compensation functions. Speed ​​control can employ constant speed and linear/S-curve acceleration/deceleration, and supports asymmetrical linear acceleration/deceleration, automatic/manual deceleration, and prevents triangular waveforms in the speed curve during quantitative drive. It features 48 digital inputs and 32 digital outputs. The controller supports RS233 communication for easy program download and updates, and data backup. The system block diagram is shown in Figure 1. 3. Working Principle The working principle is explained based on the block diagram in Figure 1. The motion controller sends pulse commands to the servo or stepper control unit to drive the motor. The maximum output pulse frequency is 4MHz. During the drive process, if an external stop signal is detected, the controller immediately issues a stop pulse output. If a hardware limit signal is detected during the drive, the drive is immediately stopped, ensuring the safety of the mechanical system. During spraying, the controller sends an output signal to control the on/off state of the spray gun. The number of pulses sent, the signals to be detected during movement, and which output operation to control can all be easily implemented through software. The pulse output of the 836 control card is a common anode, "pulse + direction" or "pulse + pulse" wiring method (as shown in Figure 2). Digital input connection (as shown in Figure 3) Digital output connection (as shown in Figure 4) 4 Software Design (1) The software system adopts a teaching programming method. The user only needs to move the corresponding axis of the machine to the desired position, and the control system will automatically memorize the coordinates of this position. For a workpiece to be processed, the processing trajectory can be determined according to the shape of the workpiece during teaching. A simple example is shown in Figure 5. If you want to process according to the route A-B-C-D-E in Figure 5, when teaching the data, first move the motion axis to point A, then record the coordinates of this position, then move the axis to point B, and record the coordinates of this position. Then the system will automatically form a line segment from A to B according to the rule of two points forming a line. The others can be completed in the same way. The speed of each segment can be set separately to ensure the spraying effect. Since some places need more paint, they can move slowly, and some places need less paint, so they can move quickly. The adjustable speed ensures the spraying effect and also ensures that the machine will not vibrate too much during movement. Of course, reciprocating spraying can also be used, repeatedly spraying the workpiece to achieve a better spraying effect. If the workpiece to be sprayed has an arc shape, as shown in Figure 6, then when teaching the data, simply record the coordinates A of the arc's starting point, B of any intermediate point, and C of the arc's ending point. The system will then automatically form an arc trajectory based on the rule that three points form an arc. Whether it is a clockwise or counterclockwise arc will be automatically determined by the order of the user's teaching data. The spraying trajectory does not necessarily have to be a standard straight line segment; it can also be an M-shaped broken line segment. It depends on the specific spraying process requirements. Because a teaching-based programming method is used, the user can specify the processing trajectory at will. For spatial arcs, when teaching the data, we can break the spatial arc into multiple small spatial straight lines to complete it, because the Adt836 card has a six-axis linear interpolation function. Of course, for spraying, the subdivided line segments do not need to be very short. The above is a simple explanation and analysis of the teaching trajectory. In actual processing, there may be operations such as cylinders. Sometimes it is necessary to detect the signal of the cylinder in position (of course, it may also be other external detection signals). At the same time, at which point to turn on the spray gun and at which point to turn off the spray gun, all of these must be completed during the teaching data. The teaching data adopts tabular programming, similar to an Excel spreadsheet. In the corresponding "input" and "output" classes, input the port number of the output operation you want to detect or execute. The system will automatically detect the input signal during processing. If there is an output operation, it will execute the corresponding output operation. Figure 2 Figure 3 [ Figure 4 Figure 5 Figure 6 Of course, during actual spraying, due to the atomization and fan-shaped function of the spray gun itself, a large atomized surface is formed during spraying. Therefore, sometimes it is not necessary for the teaching trajectory to be the shape of the workpiece. Since the table operation is very simple, insertion, deletion, copying, and modification can all be used. After the teaching is completed, a trial run can be performed. If there are any unsatisfactory parts, the above editing functions can be used to revise the data. (2) Coordinate system description: The system uses the mechanical origin as the reference coordinate system. For a six-axis system, each axis must have an origin signal. So, when teaching the data, you must first return to the origin. When the system detects the origin signal when returning to the origin, the coordinate system is set to 0 for each axis. The motion coordinates of each axis will then refer to this coordinate system. (3) In order to edit the teaching data more effectively, the teaching + instruction programming mode is adopted in the software design. Users can teach a few lines of data and use jump and loop instructions to complete multiple reciprocating spraying operations. Windows-like copy and paste function is also adopted, which can copy a whole block of data to a specified location. Combined with the insertion, deletion, modification and other editing operations, the teaching work of processing data can be realized quickly and easily. 5 Conclusion This article introduces the design of the Adt-TP104 controller based on the Adt836 motion control card in the spraying system. This controller is small in size, fast in response speed, simple to operate, and the visual human-machine interface is very convenient to operate. It has already gained a foothold in the coating industry. With the continuous improvement of technology, it will be more and more widely used in the coating industry. Proceedings of the Second Servo and Motion Control Forum Proceedings of the Third Servo and Motion Control Forum