Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment, micromanipulation, and noninvasive surgery inside the body. Untethered microrobot applications can benefit from haptic technology and telecommunication, enabling telemedical micro-manipulation. Users can manipulate the microrobots with haptic feedback by interacting with the robot operating system remotely in such applications. Artificially created haptic forces based on wirelessly transmitted data and model-based guidance can aid human operators with haptic sensations while manipulating microrobots. The system presented here includes a haptic device and a magnetic tweezer system linked together using a network-based teleoperation method with motion models in fluids. The magnetic microrobots can be controlled remotely, and the haptic interactions with the remote environment can be felt in real time. A time-domain passivity controller is applied to overcome network delay and ensure stability of communication. This study develops and tests a motion model for microrobots and evaluates two image-based 3D tracking algorithms to improve tracking accuracy in various Newtonian fluids. Additionally, it demonstrates that microrobots can group together to transport multiple larger objects, move through microfluidic channels for detailed tasks, and use a novel method for disassembly, greatly expanding their range of use in microscale operations. Remote medical treatment in multiple locations, remote delivery of medication without the need for physical penetration of the skin, and remotely controlled cell manipulations are some of the possible uses of the proposed technology.
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Controlling Homogeneous Microrobot Swarms In Vivo Using Rotating Magnetic Dipole Fields.
Future medical microrobots, which are likely to be simple microstructures with no actual computational intelligence on board, can be functionalized to perform targeted therapy in the body. In this paper, we describe how the properties of rotating magnetic dipole fields have the potential to enable in vivo swarm control for the popular class of magnetic microrobots that convert rotation into forward propulsion. The methods we describe can be used with swarms of batch-fabricated homogeneous microrobots, and do not require any localization information beyond what is realistically obtainable from medical images.
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- Award ID(s):
- 1650968
- PAR ID:
- 10174818
- Date Published:
- Journal Name:
- Robotics Research. Springer Proceedings in Advanced Robotics, vol 10.
- Volume:
- 10
- Page Range / eLocation ID:
- 3--8
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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