High-accuracy real-time controlled robotic-based bioprinting onto unknown and moving surfaces
摘要
This study aims at developing a robotic bioprinting system capable of detecting and compensating for unexpected movements or irregularities of the printing substrate in real time, thus achieving high-accuracy deposition. To this end, a fiber-optic distance sensor based on spectral domain optical coherence tomography was integrated on a commercial anthropomorphic 6-axis robot. The sensor provides a continuous signal, which is used in a feedback control system developed in Python. This system dynamically adjusts the position of the end-effector according to the distance from the printing plane, keeping it constant. The entire setup was validated by executing printing tests (planned with simple planar trajectories) on both moving and stationary non-planar substrates with a priori unknown surface geometry. Real-time controlled printing tests proved the functionality of the developed system, showing smooth results in different scenarios while highlighting significant advantages of the proposed approach against procedures without compensation. The end-effector positioning accuracy and the average printed line width deviation resulted lower than 100