RectMag3D: A Magnetic Actuation System for Steering Milli/Microrobots Based on Rectangular Electromagnetic Coils

Abstract

Milli/microrobots benefit from their small size and can perform minimally invasive surgery in a limited tissue space and eliminate the need for fine operations such as thrombus, which not only reduces trauma to patients but also shortens the recovery period after surgery. In order to realize motion control of the milli/microrobot at a small scale, the external magnetic field-based control method has a significant advantage of wireless connection, safety, and high efficiency compared to other external actuation ways. Aiming at the actuation of milli/microrobots in human tissue fluid during a medical operation, we designed a milli/microrobot magnetic actuation system called RectMag3D, which is based on rectangular electromagnetic coils. It can realize five-degree-of-freedom motion control of milli/microrobot in three-dimensional space. It has the advantage of the accurate modeling of a magnetic field from each rectangular coil. Therefore, accurate control can be achieved. In this paper, the design and modeling of the proposed system have been introduced. A linear programming algorithm has been applied to achieve fixed-point actuation and displacement actuation. Experiments show that the milli/microrobot can realize the steering and linear motion to the target point in any direction in the limited working space under the control of the magnetic actuation system.

A Cost-Effective Integrated Methodology for Electromagnetic Actuation via Visual Feedback

“…Electromagnetic actuation finds application in many engineering sectors since its driving magnetic field can easily and safely propagate through many materials and reach confined spaces. These unique features make this actuation form well-suited for multiple applications broadly related to robotics, such as electromagnetic actuation for image stabilization [1], minimally invasive microrobots for microsurgery [2][3][4][5][6][7][8], targeted drug delivery inside the human body [9,10] or early screening and cancer treatment [11], magnetic levitation (e.g., vertical motion of a ball [12]) and general motion control of ferromagnetic elements (e.g., planar steering of a ferrofluid drop [13]).…”

Electromagnetic Manipulation System for Semi-Autonomous Control of Small-Scale Magnetic Objects With Sequential Programming

“…Most systems with paired coils tend to enclose the workspace via circular [17] or square [15] coils with air cores. In contrast, distributed electromagnet-based systems usually have columnar [18] or rectangular [19] coils positioned around and pointing towards the workspace. For general electromagnets, iron cores made of soft magnetic materials with low hysteresis and high permeability are often installed inside the coils to increase the magnetic field intensity [4], [20].…”

ModMag: A modular magnetic micro-robotic manipulation device

“…Yuan et al. developed Rectmag3D, which used rectangular coils to achieve 5 degrees of freedom (DoF) control of a milli/micro- robot in 3D working space [10] . OctoMag is an electromagnetic system capable of 5 DoF manipulation that uses large, complicated, and expensive equipment [11] .…”