Although cell manipulation technologies have been adopted in a wide variety of applications, at present operators must rely solely on visual information to perform such procedures without damaging the cells. Consequently, there is an increasing demand for the integration of tactile feedback. However, conventional force sensors face significant challenges in detecting ultrafine forces exerted on soft targets such as cells. In this study, we propose an admittance-based bilateral control with reaction force estimation using an optical tweezer. The results of an experimental evaluation showed that a prototype system was able to estimate and transmit forces on the order of piconewtons to facilitate ultrafine teleoperation. Thus, our results show that the proposed approach overcomes conventional limitations in measuring ultrafine forces and enables intuitive force feedback. These capabilities are expected to reduce the difficulty of specialized microscale tasks such as cell manipulation significantly.
Otsuka et al. (2026) studied this question.