A Flexible Magnetic Soft Continuum Robot for Manipulation and Measurement at Microscale

Magnetic soft continuum robots have received interest in diverse fields, because of their active steering and remote control capabilities. However, a more challenging task is the development of magnetic soft continuum robots for analyzing the mechanical properties of biological tissue during intravascular treatments. Here, we present a force-controlled soft continuum robot with a magnetic end-effector for measurement of biological mechanical properties. The magnetically driven system contains a set of Helmholtz coils and a permanent magnet. The Helmholtz coils produce an oscillating magnetic field for overcoming friction. The permanent magnet is responsible for steering and providing traction for forward motion. The force on the magnetic tip was calibrated with a soft rod with a known elasticity coefficient. Experimental results indicated that the magnetic soft continuum robot successfully achieved manipulation and stiffness measurement of biological embryos. This strategy for mechanical property analysis of biological tissue expands the opportunities for use of soft continuum robots and broadens the field of functionalization for continuum microrobots.