1 Introduction

    With China's rapid economic development, the recent introduction of dry chemical urine analyzers and fully automatic urine sediment analyzers has enabled complete automation of routine urinalysis. This advancement not only reduces labor intensity for medical laboratory personnel but also eliminates human factors affecting sediment analysis accuracy, significantly improving both speed and reliability of urine testing. Simultaneously, it has brought operational convenience and economic benefits to large, medium, and small hospitals. This article presents a practical application case of HollySys Motor's stepper and AC servo systems in urine sediment analyzers.

2 Equipment Purpose

    The flow-through urine sediment analyzer is a fully automatic, high-efficiency instrument providing clinical urine analysis. It primarily measures eight parameters (white blood cells, red blood cells, casts, epithelial cells, crystals, mucus threads, trichomonads, and fungi) through both direct measurements and calculated values.

3 System Design

    The analyzer's electrical control system primarily consists of a power supply, PC, controller, drivers, stepper motors, and servo motors. The system employs PLC as the central controller managing all instrument operations, including mechanical movements, sample/liquid aspiration and dispensing, data collection, processing, and alarm notifications.

    The equipment utilizes "SenChuang" brand stepper motor and driver systems with modular design for robotic arm control, offering precise movement, reliable operation, and easy maintenance. A dedicated "SenChuang" servo motor system controls the automated centrifugation quantitative device. Key functions include intelligent sample numbering, high-speed centrifugation for sedimentation, automatic supernatant removal, quantitative staining, and gas mixing. Requirements include complete cell morphology preservation post-separation, precise positioning/quantification, controllable centrifugation, low noise, and minimal motor temperature rise. The servo system must deliver exceptional performance, particularly in centrifugal inertia disk operation - achieving rapid response and quiet operation at high speeds, while maintaining precision during low-speed intelligent sampling. The servo motor thus plays a critical role in equipment functionality.

4 Product Application

    The servo motor operates in position mode receiving host computer pulses for precise positioning, with electronic gear ratio adjustments matching the host system. The high-inertia centrifuge disk demands exceptional servo motor performance, especially regarding inertia matching. Through internal PID parameter optimization in the servo driver, the system achieves both precise positioning and optimal inertia matching, ensuring peak equipment performance. This demonstrates the servo motor's superior capabilities.

    To prevent external interference, all system contact points follow strict grounding standards to avoid data inaccuracies causing diagnostic errors. Equipment design requires strictly separated strong and weak current cabling. While the centrifuge uses AC 220V and microscopic inspection module uses DC 5V, all other components operate on DC 24V. The control system, mounted on the rear chassis frame, manages interconnections between PLC, PC, and components, with instrument circuits and accessories connected to the main power supply.

    Years of operational validation confirm the equipment's excellent economic and social benefits across medical institutions including municipal Grade-A hospitals and medium/small clinics. HollySys Motor's stepper and AC servo motors have consistently demonstrated superior performance, earning widespread user recognition. As a professional motion control manufacturer, HollySys Motor has successfully implemented similar solutions in textile, machining, laser processing, engraving, printing, medical, packaging, military, electronics, pharmaceutical, and financial equipment sectors, establishing itself as a leading domestic brand in motion control motors and drivers.