Abstract: This paper introduces a mobile phone flip phone durability testing system. The system consists of a National Instruments PXI-8186 controller, PXI-7344, UMI-7764, YASKAWA SGDL-04AS servo unit and SGML-04AF12 servo motor, and a virtual instrument-based user interface. This testing system minimizes system size by using virtual instruments, improves system stability, and is easy to maintain and expand, while also providing a user-friendly interface. Keywords: Virtual Instrument; Measurement System; Servo Unit; Servo Motor Abstract: A cell phone hinge test system is provided. This system is composed of an NI PXI-8186 Controller, an NI PXI-7344 Motion Controller, a UMI-7764, a YASKAWA SGDL-04AS Servo Pack, a YASKAWA SGML-04AF12 Servo Motor, and a user interface based on Virtual Instrument Technology (LabVIEW). Virtual Instrument Technology minimizes system limitations and enhances stability. The system also has a user-friendly interface and is easy to upgrade. Key words: Virtual Instrument; Measurement system; Servo Pack; Servo Motor Cell phone hinge durability testing involves repeatedly opening and closing the flip phone a preset number of times and then observing the performance of various parts of the phone. This is a crucial step in the production process of flip phones. Previous pneumatic systems were slow (approximately once every 2 seconds) and had unfriendly interfaces. This paper introduces a mobile phone flip phone durability testing system based on virtual instrument technology. The system uses an NI Motion control module to control a servo motor, achieving a speed more than four times faster than previous systems and simultaneously testing up to four mobile phones. Developed using National Instruments' LabVIEW virtual instrument platform, the system boasts a user-friendly interface. During testing, operators can fine-tune various parameters to ideal values ​​for each batch of different mobile phone models during the initial test. These parameters can be saved as configuration files for future testing of the same model, significantly reducing repetitive operations and improving system automation. 1. System Principle and Overview 1.1 Motion Control Principle The principle of motion control is simple: the motion control module sends control signals, such as pulse signals and analog voltage values. These signals correspond to position control mode and speed control mode, respectively. The servo motor receives the control signal in the corresponding mode and moves according to the predetermined pattern. However, the motor's motion has errors, especially in the simulated speed control mode. Therefore, the motor needs to send coded signals to the motion control module so that the motion control module can make corresponding compensations based on the actual motion to eliminate accumulated errors. This is especially important for a system like this one that needs to run continuously for a long time. The following figure is a simplified schematic diagram of the motion control principle: [align=center][IMG=Motion Control Principle Schematic Diagram]/uploadpic/THESIS/2007/8/20070803154608356850Q.jpg[/IMG] Figure 1 Schematic Diagram of Motion Control Principle[/align] 1.2 System Overview This system uses the NI Motion control module to control the speed of the servo motor and drives the corresponding levers and switches to control the opening and closing of the mobile phone flip cover according to the parameters set by the user. The overall system block diagram is shown in Figure 2: [align=center][IMG=Mobile Phone Flip-Type Durability Test System Block Diagram]/uploadpic/THESIS/2007/8/20070803154735992531F.jpg[/IMG] Figure 2 Mobile Phone Flip-Type Durability Test System Block Diagram[/align] The entire system consists of two parts: the motion control part and the test platform part. The motion control part uses the NI PXI controller and the NI PXI-7344 motion control module to send motion control voltage signals V-REF, which are connected to the servo motor driver through the NI UMI 7764. The test platform part includes two independent platforms, each with a set of motors controlling the opening and closing of four flip-type mobile phones under test (see Figure 3). The control signals for all four motors are provided by the four axes of the NI PXI-7344. Each motor has an coded signal fed back to the motion control module to form a closed-loop control circuit. Additionally, Forward Limit and Reverse Limit signals are fed back to the motion control module to determine the initial position of the system and prevent the motor from exceeding its limit position. [align=center][IMG=Test Platform Diagram]/uploadpic/THESIS/2007/8/2007080315513391531H.jpg[/IMG] Figure 3 Test Platform Diagram[/align] 2. Hardware Connection Hardware wiring includes the connection between the servo unit and the servo motor, and the connection between the motion control module and the servo unit. The connection between the servo unit and the servo motor has dedicated cables and corresponding terminal definitions, which are related to the type of servo unit and servo motor. The following diagram shows the connection between the motion control module and the servo unit, as well as the connection of the limit signals: [align=center][IMG=Schematic diagram of the connection between the motion control module and the servo unit and the limit signals]/uploadpic/THESIS/2007/8/2007080315540093882E.jpg[/IMG] Figure 4 Schematic diagram of the connection between the motion control module and the servo unit and the limit signals[/align] 3. Software Structure and Functions The entire software was developed using LabVIEW 7.1, an object-oriented graphical programming language from National Instruments. It consists of three layers from top to bottom: a high-level communication layer, a middle-level motion control layer, and a low-level driver and development environment support layer. The low-level development environment and driver interfaces are provided by the hardware and software vendors, including the LabVIEW 7.1 graphical programming environment and the driver for the motion control board. The middle-level motion control layer is programmed in the LabVIEW environment to implement the motion control of the motor, including the motor's position, speed, and the overall motion flow of the system. The higher-level communication layer is used to transmit various parameters set by the user to the motion control layer, and at the same time, to feed back the user's required information, such as the current motion speed and remaining time, to the user interface. 4. Operation Interface Based on Virtual Instruments This system uses LabVIEW 7.1 to design a user-friendly operation interface, as shown in Figure 5: [align=center][IMG=Mobile Phone Flip Durability Test System Operation Interface]/uploadpic/THESIS/2007/8/2007080315563528993Y.jpg[/IMG] Figure 5 Mobile Phone Flip Durability Test System Operation Interface[/align] The operation interface control functions are introduced as follows (taking Station A as an example): [align=center]Table 1 Operation Interface Control Functions[/align] Test Program Operation Steps: 1) Run the program, and the system will automatically log in as Operator. 2) The system will start initializing the motion control module. After completion, a dialog box will pop up asking whether control parameters need to be loaded. If No is selected, the system will automatically load the settings when the program was last exited and make the lever and dial move to the corresponding positions. If you select Yes, the system will continue to display a dialog box asking which platform's control parameters need to be loaded. After selection, the system loads the corresponding configuration file and moves the lever and dial to the corresponding position. 3) If the tested mobile phone model already has a corresponding configuration file, skip to step 5). If this is the first test of this model, log in as Engineer. Press the Initialize control to initialize the platform. 4) Press the Jog control to enter fine-tuning mode. Fine-tune the fixture to the ideal starting and ending positions and record the corresponding angle values. Press the OK control to return to the main panel and change control parameters #2 and #3 to the results obtained from the fine-tuning. Press Save Setting to save the current settings as the configuration file for the new model. 5) Press the Test/Continue control to start the test. 6) At this time, there are 3 different situations: ① The platform stops running after the number of flips reaches the upper limit set by control parameter #1. ② Press the Stop control to stop the operation, and control parameter #8 is reset to 0. ③ Press the Pause control to pause the operation, control parameter #8 retains its current value, and you can adjust the control parameters and continue the test. 7) Press the Exit button to exit the test system. 4. Conclusion This test system implements durability testing for flip phones, significantly improving testing speed compared to traditional test systems, and provides comprehensive and flexible user management and system setting functions. Actual production testing shows that the test system operates stably and improves the efficiency of the entire production process. References: 1. National Instruments Corporation. The Interactive Encyclopedia of Measurement and Automation, 2002. 2. Wu Qi. Automatic Control Principles. Tsinghua University Press, 1990. 3. Lei Zhenshan. LabVIEW 7 Express Practical Technical Tutorial. China Railway Publishing House, 2004.