Magneto-Acoustically Engineered Steerable Robots

Project Information

MAESTRO

Grant agreement ID: 866494

DOI

10.3030/866494

EC signature date 2 March 2020

Start date 1 February 2021

End date 31 July 2027

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 2 000 000,00

EU contribution

€ 2 000 000,00

Coordinated by

UNIVERSITEIT TWENTE
Netherlands

Periodic Reporting for period 3 - MAESTRO (Magneto-Acoustically Engineered Steerable Robots)

Reporting period: 2024-02-01 to 2025-07-31

Summary of the context and overall objectives of the project

Much advances have been made in minimally invasive surgery (MIS) as well as drug availability for cancer treatment. Early diagnosis can clearly augment effective treatment and significantly improve patient care. However, early stage lesions are very small (from 10 μm to 10 mm) and often deep-seated within the patient’s body. It is therefore, extremely challenging to perform precise localized therapy without harming the neighboring healthy tissues. This is an important technological bottleneck, as the damage of healthy tissues often involves adverse systemic side effects. To overcome this challenge, researchers have recommended the use of bioactive diagnostic and therapeutic agents. However, these agents are traditionally injected into the circulatory system in an uncontrolled manner, and visualized using non-real-time imaging modalities (e.g. magnetic resonance (MR) or molecular imaging techniques). Recently, as part of my European Research Council (ERC) Starting and Netherlands Organization for Scientific Research (NWO) VIDI grants, my team developed a range of robotically-steered needles and flexible probes, controlled using clinical imaging modalities (e.g. computed tomography, ultrasound (US), MR). These systems carry great promise for bringing microrobotic interventions closer to clinical practice. Specifically, these probes could serve as a tool to deliver micro-agents in the vicinity of a deep-seated target, where the agents would execute tasks under magnetic and acoustic guidance. Various types of micro-agents could be devised for that purpose, opening up a gamut of diagnosis and treatment options ranging from rapid on-site pathological tests and localized chemotherapy to targeted drug delivery via microcapsules. Thus, the ultimate vision and overall aim of MAESTRO is to tackle the still significant MIS challenges ahead and develop the next level integrated robotic probe steering system that will enable high-precision targeted delivery and steering of a wide range of diagnostic and therapeutic micro-agents. Such an advance would signify a true breakthrough in current MIS technology, with great impact for clinical applications for and beyond cancer.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Over the past two-and-half years, the MAESTRO-team has primarily focused on the following tasks/work packages (WPs):

WP1: Personalized model and pre-operative plan
Accurate targeting during robotic probe insertion requires a reliable and stable model representing geometry and dynamics of both the probe and its environment. These models are used to generate adequate algorithms for pre-operative planning and intra-operative control of the intervention. The objective of WP1 is to develop a personalized (patient-specific) route-map and model for pre-operative planning that predicts the path of the probe with the actuated segments.

WP2: Intra-operative control of the flexible probe
The pre-operative plan is in essence the roadmap, and provides an initial track for the flexible probe at the commencement of the intervention to reach its target. However, diversions in the probe path/target coordinates due to unmodeled perturbations have to be factored-in by developing necessary intra-operative control schemes. The objective of WP2 is to develop a robust intra-operative controller for the probe steering system operating in uncertain environments.

WP3: Robotic system for steering the flexible probe
MAESTRO will use techniques from mechanisms theory and soft robotics to design a novel probe with built‑in sensing capabilities. The multi-segmented flexible probe will be merged with innovative control strategies, and US- and FBG-based servoing to reshape the probe segments while steering it to a target. The objective of WP3 is to create, integrate, and evaluate the pre-operative plans and intra-operative control techniques to steer the magnetically-actuated probe in the proximity of the desired target.

WP4: Tracking and control of the micro-agents
The probe steering system will transport the micro-agents in close vicinity of the desired target. These agents have the potential to perform localized and personalized diagnosis and therapy. The objective of WP4 is to perform US- and fluorescence-guided tracking, and magneto-acoustic control of micro-agents using an electromagnetic- and piezoelectric-driven microrobotic system.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The following are the innovations per work package (WP).

Innovations (WP1): 1. Multi-scale model will describe the evolving shape of a probe surrounded by tissue and is applicable to other continuum-style (flexible) robots used within the context of MIS. 2. Fluorescence images coupled with US data will provide unprecedented insights for visualization of the pre-operative path, and used for both the flexible probe and micro-agents.

Innovations (WP2) : 1. Techniques will be developed to track the flexible probe using US images and FBG sensors. 2. Robust model predictive controller (RMPC) with pre-operative plans can control the flexible probe in the presence of various disturbances (while compensating for organ motion).

Innovations (WP3) : 1. Enhanced probe insertion system that includes the multi-segmented probe with soft and compliant microstructure will allow unlimited steerability and actuation functionalities. 2. Electromagnetic system will be capable of applying controlled fields/gradients, and the optimized coil configuration will have an enlarged workspace, fast response time, and high actuation bandwidth. 3. Modular design will permit both image-guided control and human-guided control, which will enable insertion and navigation of surgical instruments via the working channel of the MAESTRO probe.

Innovations (WP4): 1. Stable 3D visual tracking algorithms will track microrobots and clusters
of nanoparticles. 2. Nonlinear disturbance observer architecture will account for modeling and environmental uncertainties, while estimating interaction forces that are useful in microassembly tasks. 3. Use of 3D photolithography for monolithic fabrication provides convenient means of rapid prototyping micro-agents with dexterity over design. 4. Focused electrodeposition provides a plethora of alternatives for material selection to functionalize the agents as magneto-acoustic microrobots. 5. Prototype enables magnetic steering and acoustic release of drug loaded bio-hybrid micro-agents (e.g. doxorubicin) for personalized diagnosis.