11 research outputs found
Accelerating Surgical Robotics Research: A Review of 10 Years With the da Vinci Research Kit
Robotic-assisted surgery is now well-established in clinical practice and has
become the gold standard clinical treatment option for several clinical
indications. The field of robotic-assisted surgery is expected to grow
substantially in the next decade with a range of new robotic devices emerging
to address unmet clinical needs across different specialities. A vibrant
surgical robotics research community is pivotal for conceptualizing such new
systems as well as for developing and training the engineers and scientists to
translate them into practice. The da Vinci Research Kit (dVRK), an academic and
industry collaborative effort to re-purpose decommissioned da Vinci surgical
systems (Intuitive Surgical Inc, CA, USA) as a research platform for surgical
robotics research, has been a key initiative for addressing a barrier to entry
for new research groups in surgical robotics. In this paper, we present an
extensive review of the publications that have been facilitated by the dVRK
over the past decade. We classify research efforts into different categories
and outline some of the major challenges and needs for the robotics community
to maintain this initiative and build upon it
CathSim: An Open-source Simulator for Autonomous Cannulation
Autonomous robots in endovascular operations have the potential to navigate
circulatory systems safely and reliably while decreasing the susceptibility to
human errors. However, there are numerous challenges involved with the process
of training such robots such as long training duration due to sample
inefficiency of machine learning algorithms and safety issues arising from the
interaction between the catheter and the endovascular phantom. Physics
simulators have been used in the context of endovascular procedures, but they
are typically employed for staff training and generally do not conform to the
autonomous cannulation goal. Furthermore, most current simulators are
closed-source which hinders the collaborative development of safe and reliable
autonomous systems. In this work, we introduce CathSim, an open-source
simulation environment that accelerates the development of machine learning
algorithms for autonomous endovascular navigation. We first simulate the
high-fidelity catheter and aorta with the state-of-the-art endovascular robot.
We then provide the capability of real-time force sensing between the catheter
and the aorta in the simulation environment. We validate our simulator by
conducting two different catheterisation tasks within two primary arteries
using two popular reinforcement learning algorithms, Proximal Policy
Optimization (PPO) and Soft Actor-Critic (SAC). The experimental results show
that using our open-source simulator, we can successfully train the
reinforcement learning agents to perform different autonomous cannulation
tasks
Data-driven modelling and control of concentric tube robots with application in distal lung sampling
This research aims to explore the use of Concentric Tube Robots (CTRs) as a novel alternative
to needle-based interventions in order to make these procedures more accurate and
repeatable. CTRs due to their small footprint, compliance, and dexterity have been proposed
for several minimally-invasive robotic surgeries. As a novel flexible robot, it has the potential to
reach distal parts of the human lung that are difficult or impossible to reach with conventional
needle-based interventions. There are, however, still significant challenges associated with
the motion and position control of CTRs. Commonly used model-based control approaches
are computationally expensive to solve and often employ simplified geometric/dynamic assumptions,
which could be inaccurate in the presence of unmodelled disturbances and external
interaction forces. Consequently, this work explores different control strategies to overcome
these limitation. This is achieved by first building a simulation environment based on a
computationally improved kinematic model that enables real-time control. Then, data-driven
control approaches are investigated in order to provide accurate position control in the presence
of uncertainties in the system. Finally, a three-phase affordance-aware motion planner
is proposed to demonstrate the feasibility of using CTRs for percutaneous lung biopsy.
According to this, the first part of this work concentrates on computationally efficient real-time
modelling and simulation of CTRs. In order to achieve this, two approaches are taken. The
first one introduces a method that can rapidly estimate the solution of the kinematic model,
while the second approach focuses on implementing the existing model in a computationally
efficient way in Robot Operating System (ROS) using C++.
Second, this work explores data-driven solutions to control the robot without relying on the
kinematic model. Consequently, two data-driven solutions are proposed, namely the Hybrid
Dual Jacobian approach and the Extended Dynamic Mode Decomposition (EDMD) algorithm.
The hybrid controller combines the advantages of model-based and data-driven control approaches,
while the EDMD provides a completely model-free solution to control the robot. Both
controllers are capable of rapidly predicting the robot’s nonlinear dynamics from a limited data
set and offer consistent control under external loading and in the presence of obstacles.
The third part of the thesis explores the use of CTRs in the context of distal lung sampling. This
work demonstrates that CTRs are suitable for Needle-Based Optical Endomicroscopy where
a CTR steers a fluorescent imaging probe with cellular and bacterial imaging capability inside
soft tissue. Then, it is also demonstrated that a CTR can be used as a Steerable Needle to
reach a target deep inside the tissue. To achieve these tasks, a motion planner is essential due
to the fact that a CTR is only capable of reaching specific points in its workspace and there
are a number of configurations where the robot becomes unstable. Based on this, a threeii
phase affordance-aware motion planner algorithm is developed. The motion planner selects
the best entry point for a specific task. Based on the selected entry point it first generates
a stable trajectory from the robot’s initial configuration to the selected entry point. Then, a
feasible trajectory is generated from the entry point to the target. Finally, the proposed datadriven
control algorithm is applied to autonomously steer the robot on the generated trajectory
toward the target region for endomicroscopic imaging
Reliability Assessment Model for Industrial Control System Based on Belief Rule Base
This paper establishes a novel reliability assessment method for industrial control system (ICS). Firstly, the qualitative and quantitative information were integrated by evidential reasoning(ER) rule. Then, an ICS reliability assessment model was constructed based on belief rule base (BRB). In this way, both expert experience and historical data were fully utilized in the assessment. The model consists of two parts, a fault assessment model and a security assessment model. In addition, the initial parameters were optimized by covariance matrix adaptation evolution strategy (CMA-ES) algorithm, making the proposed model in line with the actual situation. Finally, the proposed model was compared with two other popular prediction methods through case study. The results show that the proposed method is reliable, efficient and accurate, laying a solid basis for reliability assessment of complex ICSs
Robot Assisted Object Manipulation for Minimally Invasive Surgery
Robotic systems have an increasingly important role in facilitating minimally invasive surgical treatments. In robot-assisted minimally invasive surgery, surgeons remotely control instruments from a console to perform operations inside the patient. However, despite the advanced technological status of surgical robots, fully autonomous systems, with decision-making capabilities, are not yet available.
In 2017, a structure to classify the research efforts toward autonomy achievable with surgical robots was proposed by Yang et al. Six different levels were identified: no autonomy, robot assistance, task autonomy,
conditional autonomy, high autonomy, and full autonomy. All the commercially available platforms in robot-assisted
surgery is still in level 0 (no autonomy). Despite increasing the level of autonomy remains an open challenge, its adoption could potentially introduce multiple benefits, such as decreasing surgeons’ workload and fatigue and pursuing a consistent
quality of procedures. Ultimately, allowing the surgeons to interpret the ample
and intelligent information from the system will enhance the surgical outcome and
positively reflect both on patients and society. Three main aspects are required to
introduce automation into surgery: the surgical robot must move with high precision,
have motion planning capabilities and understand the surgical scene. Besides
these main factors, depending on the type of surgery, there could be other aspects
that might play a fundamental role, to name some compliance, stiffness, etc. This
thesis addresses three technological challenges encountered when trying to achieve
the aforementioned goals, in the specific case of robot-object interaction. First,
how to overcome the inaccuracy of cable-driven systems when executing fine and
precise movements. Second, planning different tasks in dynamically changing environments.
Lastly, how the understanding of a surgical scene can be used to solve
more than one manipulation task.
To address the first challenge, a control scheme relying on accurate calibration is
implemented to execute the pick-up of a surgical needle. Regarding the planning of
surgical tasks, two approaches are explored: one is learning from demonstration to
pick and place a surgical object, and the second is using a gradient-based approach
to trigger a smoother object repositioning phase during intraoperative procedures.
Finally, to improve scene understanding, this thesis focuses on developing a simulation
environment where multiple tasks can be learned based on the surgical scene
and then transferred to the real robot. Experiments proved that automation of the pick and place task of different surgical objects is possible. The robot was successfully
able to autonomously pick up a suturing needle, position a surgical device for
intraoperative ultrasound scanning and manipulate soft tissue for intraoperative organ
retraction. Despite automation of surgical subtasks has been demonstrated in
this work, several challenges remain open, such as the capabilities of the generated
algorithm to generalise over different environment conditions and different patients
Large space structures and systems in the space station era: A bibliography with indexes (supplement 03)
Bibliographies and abstracts are listed for 1221 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1991 and June 30, 1991. Topics covered include large space structures and systems, space stations, extravehicular activity, thermal environments and control, tethering, spacecraft power supplies, structural concepts and control systems, electronics, advanced materials, propulsion, policies and international cooperation, vibration and dynamic controls, robotics and remote operations, data and communication systems, electric power generation, space commercialization, orbital transfer, and human factors engineering