Abstract Polymerase chain reaction (PCR) testing is an effective testing method for diagnosing infectious diseases, and it has been the prim
Abstract Polymerase chain reaction (PCR) testing is an effective testing method for diagnosing infectious diseases, and it has been the primary testing method during the novel coronavirus disease (COVID-19) pandemic. PCR tests (from specimen collection to result acquisition) involve a pretreatment process, ribonucleic acid extraction, and real-time PCR testing. From the perspective of infection and contamination risks, there is significance in automating the pretreatment process, where centrifuge tubes, cryopreservation tubes, and microtubes are used. Many automated systems have been designed for centrifuge tubes with screw-type caps; however, few systems have been designed for microtubes with press-type caps. Pipetting robot system for microtubes with press-type caps have been proposed; however, these systems use vertical articulated robot arms and are thus bulky. Small microtube cappers that can be incorporated into compact automated pipetting robot systems and are compatible with a wide range of microtubes have not been developed. Thus, in this study, we developed a small microtube capper/decapper system that can be used with a wide variety of microtubes. First, to clarify the required specifications for the microtube capper/decapper system, the shapes and opening/closing forces of 15 types of microtubes from 10 manufactures were measured. Then, conceptual, basic, and control system design processes were performed based on the identified requirements. Finally, a prototype model of the proposed microtube capper/decapper system was developed, and verification experiments and pipetting evaluation experiment with a Cartesian robot were performed. The results confirmed that the proposed system can open and close the caps of 15 different types microtubes and the proposed microtube capper/decapper can be incorporated into a Cartesian robot system to perform pipetting tasks. Although its operation time was longer than that of a human operator, it will help reduce the burden on operators, decrease infection risks, and improve the reliability of the results of clinical examinations and biological experiments. We believe that the proposed system can be used to automate similar tasks in not only the pretreatment process of PCR tests but also a wide range of clinical examinations and biological experiments.
