38 accepted papers
Magnetic actuation enables contactless control of medical microrobots and instruments and offers the potential for improved safety and effectiveness in robot-assisted minimally invasive surgery. While much research is being conducted on the development of surgical devices, there is a lack of externa…
Microrobotics implies actuation-related constraints that make safe telemanipulation particularly challenging. We present a haptic shared control system for electromagnetic-based telemanipulation of a pair of microrobots using a constrained optimization framework. Our contributions include: (1) a Qua
Magnetic microrobots have the ability to navigate through difficult-to-reach environments, thereby holding promise for applications in the fields of micromanipulation and biomedicine. The actuation of these microrobots requires the generation and control of magnetic fields and gradients. However, th
Soft and flexible magnetic robots have gained significant attention in the past decade. These robots are fabricated using magnetically-active elastomers, are capable of large deformations, and are actuated remotely thus allowing for small robot size. This combination of properties is appealing to th
Guiding catheters assist in delivering hazardous equipment such as needles through non-solid mediums likecavities and vasculature. Traditionally, metallic needles are passed through metallic guiding catheters, which are limited to linear paths or require anatomy-specific designs. Recently, variable
The actuation of miniaturized robots through external magnetic fields has great potential for medical applications. The controllability properties of the miniaturized robots are affected by magnetic field generation modality. In this work, the magnetic field of a mobile electromagnet, notably capabl
Electromagnetic actuation of micro-/milli-sized agents has traditionally relied on large electromagnets positioned at considerable distances from the agents. As a result, the electromagnets consume kilowatts of power to overcome the limited generation of magnetic field gradients. Miniaturized electr
Minimally-invasive surgery (MIS) for stent implantation is a complex procedure requiring specialized instruments. It often leads to prolonged patient recovery, and interrupted operations due to incorrect instrument selection and complex anatomy. This study presents a novel magnetic navigation system
Magnetic actuation of minimally invasive medical tetherless devices holds great promise in several biomedical applications. However, there are still several challenges in noninvasive localization, both in terms of sensing detectable signals of these devices and estimating their states. In this work,
Magnetically-actuated soft robots have potential for medical application but require further innovation on functionality and biocompatibility. In this letter, a multi-segmented snake-inspired soft robot with dissolvable and biocompatible segments is designed. The actuation response under external ma
Small untethered soft robots have potential for diverse applications, particularly in constrained spaces where the use of a tethered device would be infeasible. Examples include biomedical applications such as brachytherapy, fine-needle biospy and micro-needle drug delivery. To advance soft robots t…
We present a haptic teleoperation system capable of steering flexible needles under ultrasound imaging toward a target. With respect to similar works, this approach enables intuitive control of the needle motion while providing the user with 3D navigation and needle tip cutting force using a combina
In the past decade, remote actuation through magnetic fields has been used for position and orientation control of continuum manipulators (CMs) with a single magnet at the distal tip. By leveraging multiple points of actuation along the length of the CM it is possible to achieve increasingly complex
Control of tetherless magnetically actuated helical robots using rotating dipole fields has a wide variety of medical applications. The most promising technique in manipulation of these robots involves a rotating permanent magnet controlled by a robotic manipulator. In this work, we study the open-l…
Magnetically-driven screws operating in soft-tissue environments could be used to deploy localized therapy or achieve minimally invasive interventions. In this work, we characterize the closed-loop behavior of magnetic screws in an agar gel tissue phantom using a permanent magnet-based robotic syste…
Magnetically actuated soft robots have recently been identified for application in medicine, due to their potential to perform minimally invasive exploration of human cavities. Magnetic solutions permit further miniaturization when compared to other actuation techniques, without loss in functionalit…
Advancements in medical microrobotics have given rise to an abundance of agents capable of localised interaction with human body in small scales. Nevertheless, clinically-relevant applications of this technology are still limited by the auxiliary infrastructure required for actuation of micro-agents
Additive manufacturing (AM) is one of the emerging production methodologies transforming the industrial landscape. However, application of the technology in fluidic power transmission and actuation is still limited. AM pneumatic stepper motors have been previously introduced to the field of image-gu
Positioning conventional endovascular catheters is not without risk, and there is a multitude of complications that are associated with their use in manual surgical interventions. By utilizing surgical manipulators, the efficacy of remote-controlled catheters can be investigated in vivo. However, te
Soft materials with embedded magnetic properties can be actuated in a contactless manner for dexterous motion in restricted and unstructured environments. Magnetic soft robots have been demonstrated to be capable of versatile and programmable untethered motion. However, magnetic soft robots reported…
Magnetic soft robots have the combined advantages of contactless actuation, requiring no on-board power source, and having flexible bodies that can adapt to unstructured environments. In this study, four milli-scale soft robots are designed (Inchworm, Turtle, Quadruped, and Millipede) and their actu
Catheterization instruments are increasingly being improved to accurately diagnose and treat cardiovascular conditions. However, current catheter systems provide limited information about the shape of the catheter and tissue-instrument interaction forces during an intervention. Furthermore, relying…
Minimally invasive surgery can benefit greatly from utilizing micro-agents. These miniaturized agents need to be clearly visualized and precisely controlled to ensure the success of the surgery. Since medical imaging modalities suffer from low acquisition rate, multi-rate sampling methods can be use…
Minimally invasive surgery involves using flexible medical instruments such as endoscopes and catheters. Magnetically actuated catheters can provide improved steering precision over conventional catheters. However, besides the actuation method, an accurate tip position is required for precise contro…
Needle insertion procedures under ultrasound guidance are commonly used for diagnosis and therapy. It is often critical to accurately reach a targeted region, and this can be difficult to achieve due to intraoperative tissue motion. In this letter, we present a method to steer a beveled-tip flexible
Microrobotics is a promising field that can revolutionize fields such as minimally invasive surgery. Applications such as micromanipulation can be performed more effectively using multiple microsized agents. These can be performed more accurately with the help of robust controllers. In this letter,
Pneumatic stepper motors are one of the promising alternative actuation methods for motion control in environments where electromagnetic (EM) motors cannot be used. Due to the lack of commercial off-the-shelf products, researchers working on MR compatible robotics have to develop their own pneumatic…
The presence of force feedback in medical instruments has been proven to reduce tissue damage. In order to provide force feedback, information about the interaction forces between the instrument and the environment must be known. Direct measurement of these forces by commercial sensors is not feasib…
Magnetic interaction can be utilized for remote actuation of surgical manipulators. However, platforms currently available for that purpose have limited workspaces, inadequate field strength or very low bandwidth of the electrical subsystem. In this paper, we present BigMag, a novel platform capable…
Soft miniaturized untethered grippers can be used to manipulate and transport biological material in unstructured and tortuous environments. Previous studies on control of soft miniaturized grippers employed cameras and optical images as a feedback modality. However, the use of cameras might be unsu…
The use of magnetic resonance (MR) images for needle-based interventions offers several advantages over other types of imaging modalities (e.g., high tissue contrast and no radiation). However, MR-guided interventions face challenges related to electromagnetic compatibility of medical devices and re…
Micro-sized agents can benefit robotic minimally invasive surgery since they can be inserted into the human body and use natural pathways such as arteries and veins or the gastrointestinal tract, to reach their target for drug delivery or diagnosis. Recently, miniaturized agents with shape-changing…
Needle insertion procedures are commonly performed in current clinical practice for diagnostic and therapeutic purposes. Although prevailing technology allows accurate localization of lesions, they cannot yet be precisely targeted. Needle steering is a promising technique to overcome this challenge.
Needle insertions are common during surgical procedures. Accurately delivering the needle at a specific location in the human body is of importance for the clinical outcome of the procedure. Studies have already shown that robotically inserting traditional needles with a bevel tip can improve target…
In contact micromanipulation, the adhesive forces between manipulators and microobjects decrease the chances of achieving successful releases at the desired positions. We study a non-contact micromanipulation technique of microbeads (300 µm in average diameter) using clusters of paramagnetic micropa…
In targeted therapy, clusters of drug carriers (nanoparticles and microparticles) could be in contact with a surface such as the lumen of blood vessels and the interior of the gastrointestinal tract. We study the motion characteristics of clusters of microparticles when they slide on a surface under…
We control the motion of helical microrobots with average diameter of 500 µm in two-dimensional (2D) and three-dimensional (3D) spaces using two synchronized rotating dipole fields. The utilization of the two synchronized dipole fields not only increases the magnetic torque exerted on the magnetic d…
Flexible bevel-tipped needle steering has been an active research topic since the last decade. However, most of the work presented so far performs flexible needle steering in static phantoms or non-static virtual environments. The insertion of flexible bevel-tipped needles into soft-tissue subjected…