Search

The MiniMag is a magnetic manipulation system capable of 5 degree-of-freedom (5-DOF) wireless magnetic control of an untethered microrobot (3-DOF position, 2-DOF pointing orientation). The system has a spherical workspace with an intended diameter of approximately 10 mm, and is completely unrestrained in the rotational degrees-of-freedom. This is accomplished through the superposition of multiple magnetic fields, and capitalizes on a linear representation of the coupled field contributions of multiple softmagnetic- core electromagnets acting in concert. The prototype system consists of 8 stationary electromagnets with ferromagnetic cores, and is capable of producing magnetic fields in excess of 20 mT and field gradients in excess of 2 T/m at frequencies up 2 kHz.

The progress of wet age-related macular degeneration can now be controlled by intravitreal drug injection. This approach requires repeated injections, which could be avoided by delivering the drug to the retina. Intraocular implants are a promising solution for drug delivery near the retina. Currently, their accurate placement is challenging, and they can only be removed after a vitrectomy. In this paper, we introduce an approach for minimally invasive retinal drug delivery using magnetic intraocular inserts. We briefly discuss the electromagnetic-control system for magnetic implants and then focus on evaluating their ability to move in the vitreous humor. The mobility of magnetic intraocular implants is estimated in vitro with synthesized vitreous humors, and ex vivo with experiments on cadaver porcine eyes. Preliminary results show that with such magnetic implants a vitrectomy can be avoided.