Design of Novel End-effectors for Robot-assisted Swab Sampling to Combat Respiratory Infectious Diseases.

The COVID-19 outbreak has caused the mortality worldwide and the use of swab sampling is a common way of screening and diagnosis. To combat respiratory infectious diseases and assist sampling, robots have been utilized and shown promising potentials. Nonetheless, a safe, patient-friendly, and low-cost swabbing system would be crucial for the practical implementation of robots in hospitals or inspection stations. In this study, we proposed two recyclable and cost-efficient end-effector designs that can be equipped at the distal end of a robot to passively regulate or actively sense the force exerted onto patients. One way is to introduce passive compliant mechanisms with soft material to increase the flexibility of the swabbing system, while the other way is utilizing a force-sensing gripper with embedded optoelectronic sensors to actively sense the force or torque. The proposed designs were modelled computationally and tested experimentally. It is identified that the passive compliant mechanisms can increase the flexibility of the swabbing system when subjected to the lateral force and mitigate the vertical force resulted from buckling. The lateral force range that the force-sensing gripper can detect is 0-0.35 N and the vertical force range causing buckling effect that can be sensed by gripper is 1.5-2.5 N.