30 accepted papers
Localization and mapping of an environment are crucial tasks for any robot operating in unstructured environments. Time-of-flight (ToF) sensors (e.g.,~lidar) have proven useful in mobile robotics, where high-resolution sensors can be used for simultaneous localization and mapping. In soft and contin…
Follow-the-leader (FTL) motion exploits the unique morphology of continuum robots (CRs) to navigate confined spaces by having the body retrace the path of the tip. While extensively studied, existing FTL methods typically assume a fixed base or a single degree-of-freedom insertion mechanism, limitin…
Tendon-driven continuum robots (TDCRs) have the potential to be used in minimally invasive surgery and industrial inspection, where the robot must navigate narrow and confined spaces. We propose a model predictive controller (MPC) to leverage the non-linear kinematics and redundancy of TDCRs for who
In this paper, we propose a dynamic model and control framework for tendon-driven continuum robots (TDCRs) with multiple segments and an arbitrary number of tendons per segment. Our approach leverages the Clarke transform, the Euler-Lagrange formalism, and the piecewise constant curvature assumption
Continuum robots are promising candidates for interactive tasks in medical and industrial applications due to their unique shape, compliance, and miniaturization capability. Accurate and real-time shape sensing is essential for such tasks yet remains a challenge. Embedded shape sensing has high hard
Concentric tube continuum robots utilize nested tubes, which are subject to a set of inequalities. Current approaches to account for inequalities rely on branching methods such as if-else statements. It can introduce discontinuities, may result in a complicated decision tree, has a high wall-clock t…
Tendon-driven continuum robots (TDCRs), with their flexible backbones, offer the advantage of being used for navigating complex, cluttered environments. However, to do so, they typically require multiple segments, often leading to complex actuation and control challenges. To this end, we propose a n
The small size, high dexterity, and intrinsic compliance of continuum robots (CRs) make them well suited for constrained environments. Solving the inverse kinematics (IK), that is finding robot joint configurations that satisfy desired position or pose queries, is a fundamental challenge in motion p
Various design modifications have been proposed for tendon-driven continuum robots to improve their stiffness and workspace. One of them is using locking mechanisms to constrain the lengths of rods or passive backbones along the robot. However, physics-based models used to predict these robots' beha
Establishing a physics-based model capturing the kinetostatic behavior of concentric tube continuum robots is challenging as elastic interactions between the flexible tubes constituting the robot result in a highly non-linear problem. The Goldstandard physics-based model using the Cosserat theory of…
Tendon-driven continuum robots show promise for use in surgical applications as they can assume complex configurations to navigate along tortuous paths. However, to achieve these complex robot shapes, multiple segments are required as each robot segment can bend only with a single constant curvature…
Due to the compliance of tendon-driven continuum robots, carrying a load or experiencing a tip force result in variations in backbone curvature. While the spatial robot configuration theoretically needs an infinite number of parameters for exact description, it can be well approximated using Euler A
In this letter, a novel spatial parallel continuum robot is proposed. It is composed of three tendon-actuated continuum robots as kinematic chains that are coupled at a common end effector platform by spherical joints. A modular design approach is used, allowing the reconfiguration of each continuum
We introduce a methodology to compute the inverse kinematics for concentric tube continuum robots from a desired shape as input. We demonstrate that it is possible to accurately learn joint parameters using neural networks for a discrete point-wise shape representation with different discretization.…
Due to the continuous and flexible nature of continuum robot backbones and the infinite number of parameters required to represent them in configuration space, modeling them accurately and in real-time is challenging. While the constant curvature assumption provides a simple alternative, it is limit…
Joint level calibration is an integral part of robotics as it directly influences the achievable accuracy. As opposed to serial robotic arms, continuum robots are not composed of any rigid links or joints, but of elastic materials that undergo bending and torsion. The jointless composition requires
In this work, a novel planar parallel continuum robot (PCR) is introduced, consisting of three kinematic chains that are coupled at a triangular end-effector platform and include tendon-actuated continuum segments. The kinematics of the resulting structure are derived by adapting the descriptions fo
Continuum robots actuated by tendons are a widely researched robot design offering high dexterity and large workspaces relative to their volume. Their flexible and compliant structure can be easily miniaturized, making them predestined for applications in difficult-to-reach and confined spaces. Adap
This paper investigates the influence of different joint space and orientation representations on the approximation of the forward kinematics. We consider all degrees of freedom in three dimensional space SE(3) and in the robot's joint space Q. In order to approximate the forward kinematics, differe…
Smooth position and orientation interpolation has a great effect on the performance of robot manipulators. Interpolation between several via positions can be done in a straightforward manner, which is well covered in the literature. However, generating a suitable trajectory between several orientati
This letter deals with the development of a vision-based controller for a continuum robot architecture. More precisely, the controlled robotic structure is based on three-tube concentric tube robot (CTR), an emerging paradigm to design accurate, miniaturized, and flexible endoscopic robots. This app
Recent physics-based models of concentric tube continuum robots are able to describe pose of the tip, given the preformed translation and rotation in joint space of the robot. However, such model-based approaches are associated with high computational load and highly non-linear modeling effort. A da…
Dual-arm continuum robots have been considered mainly for teleoperation, where human perception and cognition permitted coordination, and collision-free motions. This letter describes theoretical investigations on automation of dual-arm robots constituted of two concentric tube continuum manipulator
Tendon-driven continuum robots possess versatile application capabilities and have a robust design. The actuation of such robots with non-straight tendons that wrap around the backbone, described by a variable function, offers a lot of untapped potentials. While it has been shown that these continuu…
Continuum manipulators possess the ability to travel on nonlinear paths and avoid obstacles in confined environments. A variety of designs were proposed for several applications, such as minimally invasive surgery or inspections and maintenance in hazardous spaces. While hyperredundant robots can fo…
This letter presents a new heuristic 3-D volume coverage path planning (VCPP) algorithm for robotic intracerebral hemorrhage evacuation. In contrast to existing 3-D planning techniques, the proposed algorithm generates 3-D paths without first decomposing the volume into series of 2-D planning proble
Path following and follow-the-leader motion is particularly desirable for minimally-invasive surgery in confined spaces which can only be reached using tortuous paths, e.g. through natural orifices. While path following and followthe- leader motion can be achieved by hyper-redundant snake robots, th
Tendon-driven continuum robots offer increased dexterity and manipulability in comparison to conventional rigid link serial manipulators. Being able to conform to complex curves in 3D space, continuum robots are in particular useful for applications in restricted and hardly accessible environments.…
Tubular continuum robots are particularly useful for minimally invasive surgery due to their small size and ability to dexterously manipulate in constrained environments. The robot can be used teleoperated or operated (semi-)autonomously. In both cases, safe manipulation has to be ensured considerin…
Several robotic systems have been proposed for removing blood from the brain in patients who have undergone a hemorrhagic stroke. In this paper we explore the use of imagebased feedback to address tissue deformation when aspirating a hemorrhage in a phantom model. This is the first time intraoperati…