Application of integrated stepper servo motor in automatic liquid handling workstation

With the rapid development of industrial automation, automated liquid handling workstations are playing an increasingly important role in fields such as pharmaceuticals, food, and chemicals. Integrated stepper servo motors, as highly integrated drive components featuring high precision, high speed, and high stability, are widely used in automated liquid handling workstations. This article provides a detailed introduction to the application and advantages of integrated stepper servo motors in automated liquid handling workstations.

01. Introduction

Automated Liquid Handling Workstation

With the development of industrial automation, traditional pneumatic systems in automated liquid handling workstations are gradually being replaced by electrified integrated drive systems.

An automated liquid handling workstation mainly consists of the following components:

• Sampling System: Used to extract a certain volume of liquid sample from a liquid container. Common electric self-priming pipettes can achieve quantitative sampling by controlling motor speed and time.

• Distribution System: Distributes the sampled liquid into different detection containers. Typically uses an electronically controlled vertical multi-channel dispenser that can dispense to containers with different barcode labels.

• Detection System: Performs detection and analysis on the distributed liquid samples, using an automatic pick-and-place device compatible with the detection instruments.

• Transport System: Transports samples and reagents between different stations to complete sampling, distribution, testing, and other processes.

• Control System: Collects station status signals and controls actuators to complete the automatic workflow.

• Software System: Configures the control logic for sampling, distribution, and transport to complete automated operations.

02. Application Solution

Liquid Detection Unit in Automated Liquid Handling Workstation

In the liquid detection system, integrated stepper servo motors can achieve high-speed precision positioning, enabling fast and stable sampling and distribution processes and improving detection efficiency.

• Motor Model: STM2832B

• Control Modes: Profile Position Mode / Profile Torque Mode / Home Return Mode

Three motors are controlled by a microcontroller:

• One motor drives the tray movement;

• One motor lifts the disc in the tray in torque mode;

• One motor uses friction to move the disc to the 15° position and perform home return, ensuring that the 24 holes on the disc are precisely aligned with the spectral sensor.

Advantages of Integrated Stepper Servo Motors

• High integration improves equipment portability: Integrates stepper motors, drivers, encoders, and controllers into a single unit, significantly reducing equipment size and weight while simplifying wiring and reducing potential failure points.

• Flexibility to meet diverse needs: Supports CAN/CANopen/Modbus communication, allowing flexible control and adjustment according to different work requirements.

• High-precision positioning improves measurement accuracy: High positioning accuracy enables precise positioning of mobile equipment.

• Multiple control modes: Supports PP, VM, PV, PT, HM, IP, CSP, CSV, CST standard modes, as well as NiMotion position mode, speed mode, and torque mode.

• High-speed response improves equipment efficiency: Fast response speed enables quick adjustment of equipment angle and position, improving work efficiency.

• Comprehensive alarm function: Power-on self-diagnosis can detect hardware faults in a timely manner; equipped with multiple safety protection functions including overvoltage/undervoltage, overheat, overcurrent, and stall alarms. LED flashing alarm intuitively displays the current status of the motor.