Design and Implementation of a Microliter-Scale Batch Test Tube Pipetting Device Based on Mega2560 and RS485 Communication

DOI: https://doi.org/10.62517/jbdc.202601222

Author(s)

Yichong Li1, Leheng Wang1, Changtao Yang1, Yicheng Shen1, Guanghong Xin1,2

Affiliation(s)

1Sanya University, New Energy and Intelligent Connected Vehicle College, Sanya, Hainan, China 2Zhai Mingguo Academic Workstation of Sanya University, Sanya, Hainan, China

Abstract

To address the issues of low efficiency, large errors in traditional manual pipetting methods, and the high cost of existing automated pipetting equipment, a microliter-scale batch test tube pipetting device based on the Mega2560 microcontroller was designed. The device employs the RS485 differential communication protocol for precise control of the syringe pump, combined with a TB6600 driver for NEMA 17 stepper motors and a three-axis positioning system to achieve accurate liquid transfer from batch test tubes. The mechanical structure adopts an aluminum alloy profile modular framework, with collision sensors for positioning calibration and safety limit detection. The system is equipped with an industrial touch screen, supporting one-button parameter setting and real-time monitoring. Test results show that the device controls pipetting error within ±0.40 g (relative error ≤0.5%) in 50 mL and 100 mL fixed-volume pipetting tests, with stable performance during 8-hour continuous operation, and the cost is controlled within 10,000 CNY, providing an economical and practical automated pipetting solution for small and medium-sized laboratories.

Keywords

Microliter-Scale Pipetting; Mega2560 Microcontroller; RS485 Communication; Stepper Motor; Batch Test Tubes; Automated Device

References

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