Towards large-scale haptic virtual reality training for micro-robotic cell injection

This paper presents a large-scale VR training system for the micro-robotic cell injection procedure. The system was developed utilizing state-of-the-art facilities including four large screens able to be configured to three different display configurations. To interact with the system, a large workspace cable-driven haptic device was utilized as the input controller. The input controller used to manipulate the virtual micropipette can be set to two different haptic guidance modes, haptic disabled or haptic enabled. In the haptic enabled mode the user will be provided with virtual fixtures and force feedback in order to guide them to perform a successful injection. This paper also considers the range of existing cell biomechanical parameters. A virtual cell architecture to be utilized in the system is presented. The virtual cell was modelled to have a spherical membrane which provides gradually increasing repulsive force feedback to user's hand when contacted by the virtual micropipette. Then the repulsive force feedback will suddenly drop once the micropipette tip reaches the threshold length to replicate the deformation and rupture of the cell membrane. Nine participants were recruited in an experiment conducted to investigate the practicality of the cell model. It was found that the gradually increasing repulsive force feedback and the sudden force drop were felt by the participants and had assisted them in estimating the appropriate force to apply during the cell membrane penetration.