Conference Proceeding

OctoMag: An electromagnetic system for 5-DOF wireless micromanipulation.

Inst. of Robot. & Intell. Syst., ETH Zurich, Zurich, Switzerland
Proceedings - IEEE International Conference on Robotics and Automation 01/2010; DOI:10.1109/ROBOT.2010.5509857 In proceeding of: IEEE International Conference on Robotics and Automation, ICRA 2010, Anchorage, Alaska, USA, 3-7 May 2010
Source: DBLP

ABSTRACT We demonstrate five-degree-of-freedom (5-DOF) wireless magnetic control of a fully untethered microrobot with a magnetic steering system we call OctoMag. Although only occupying a single hemisphere, this system is capable of isotropically applying forces on the order of 1-40 μN with unrestricted control of the 2 orienting DOF. These capabilities are enabled through the use of soft-magnetic-cores which provide an increase of approximately 20× that of air cores in magnetic-field strength, but comes at the cost of more complicated interactions between coils. We propose a modeling mechanism that assumes the field contributions of the individual currents superimpose linearly when using cores with large linear regions and negligible hysteresis. When designing the system, the locations and quantity of electromagnets were optimized with regards to the force generation in the worst-case direction predicted by the model. The resultant system is capable of both open and closed-loop operation over a workspace of 4 cm3. OctoMag was primarily designed for the control of intraocular microrobots for delicate retinal procedures, but also has potential uses in other medical applications or micromanipulation under an optical microscope.

0 0
1 Bookmark
  • [show abstract] [hide abstract]
    ABSTRACT: Microactuators are an important tool for precise manipulation of components and materials in nanotechnologies. The problems of design and application of microactuators for micro- and nanopositioning, microassembly, and microrobotics are considered in this paper. The basic parameters and models of piezoelectric, magnetostriction, electromagnetic, electrostatic, electrothermal, and hybrid microactuators are described. A general information approach that implies the description of physical models used in order to analyze microactuator behavior and optimize their design is considered.
    Automatic Documentation and Mathematical Linguistics 12/2011; 45(6).
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: We use a cluster of paramagnetic microparticles to carry out a wireless two-dimensional microassembly operation. A magnetic-based manipulation system is used to control the motion of the cluster under the influence of the applied magnetic fields. Wireless motion control of the cluster is implemented at an average velocity and maximum position tracking error of 144 µm/s and 50 µm, respectively. This control is used to achieve point-to-point positioning of the cluster, manipulation of mi-croobjects, and assembly of microobjects into a microstructure. The control system achieves stable positioning of the cluster, while simultaneously compensating for the planar drag forces on the cluster and the microobject. The presented magnetic-based microassembly technique allows for the selective pushing and pulling of microobjects with specific geometries towards their destinations inside a microstructure in an execution time of 18 s, within a workspace of 1.8 mm × 2.4 mm.
    2013 IEEE International Conference on Robotics and Automation (ICRA); 05/2013
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: The synthesis of a porous polysulfone (PSU) coating for use in drug delivery applications is presented. PSU can serve as a functional surface coating for drug delivery vehicles, such as intraocular biomicrorobots. The coatings can be applied using spin coating or dip coating. The porosity is introduced by selectively dissolving calcium carbonate nanoparticles embedded in the bulk polymer. The network of pores thus formed increases by a factor of thirty the amount of Rhodamine B (model drug) that can be loaded and by a factor of fifteen the amount that can be released. The films do not affect cell viability and exhibit poor cell adhesion. The straightforward synthesis and predictability of porosity enables the tuning of the amount of drug that can be loaded.
    Biomedical Microdevices 03/2012; 14(3):603-12. · 2.72 Impact Factor

Full-text (2 Sources)

Available from
Mar 14, 2013