Abstract: This system is mainly used for detecting the sideslip of automobile wheels. To ensure that the steering wheels of an automobile roll in a straight line without lateral slippage, the wheel camber angle and wheel toe-in angle must be properly matched. When the wheel toe-in value and wheel camber angle are not properly matched, the wheel may not roll purely during straight-line travel, resulting in lateral slippage. When this slippage is too severe, it will destroy the wheel's adhesion conditions, lose its directional driving ability, cause traffic accidents, and lead to abnormal tire wear. The magnitude and direction of lateral slippage can be detected using an automobile wheel sideslip test bench. Sideslip test bench structure diagram: System hardware configuration: 2 displacement sensors, 2 sets of photoelectric switches, analog input module, digital input module. System working principle: When the wheel steps onto the sideplate, the first set of photoelectric switches closes (the photoelectric switches are normally open when not blocked). When the wheel leaves the sideplate, the second set of photoelectric switches closes. At this time, the sideslip of the wheel is recorded, and one set of wheel tests is completed. The wheels step onto the sideplates one by one, and the sideslip is recorded in the same way to complete the sideslip test of the entire vehicle. Functional Structure Diagram: System Functions: Vehicle Positioning: The system provides three different vehicle positioning systems: single-axle positioning, dual-axle positioning, and multi-axle positioning. Multi-axle positioning requires detecting the sideslip of six wheel sets. System Settings: Upper and lower alarm limits for sideslip, the length of the skid plate, and the logo of the vehicle being tested can be set. Customer Management: Information about tested vehicles can be recorded and modified, and printing is supported. Function Implementation: I. Single-Axle Interface: The two gauges in the diagram display the current sideslip, with different scale background colors depending on the value range. The alarm light changes color when the error of one axle exceeds the set value. II. Dual-Axle Test: Also provides gauges to display sideslip. The alarm light flashes when the sideslip exceeds the set value. III. Multi-Axle Test: Displays the differential mode error and common mode error of each wheel set, showing arrows on both sides according to different values, with different colors for different value ranges. Each set of sideslip is automatically recorded during the testing process, eliminating the previous manual recording process and improving test accuracy.