Deformable object manipulation (DOM) is an emerging research problem in robotics. The ability to manipulate deformable objects endows robots with higher autonomy and promises new applications in the industrial, services, and health-care sectors. However, compared to rigid object manipulation, the manipulation of deformable objects is considerably more complex and is still an open research problem. Addressing DOM challenges demands breakthroughs in almost all aspects of robotics: hardware design, sensing, (deformation) modeling, planning, and control. In this article, we review recent advances and highlight the main challenges when considering deformation in each subfield. A particular focus of our article lies in the discussions of these challenges and proposing future directions of research.

Accurate placement and stable fixation are the main goals of internal fixation of bone fractures using the traditional medical screws. These goals are necessary to expedite and avoid improper fracture healing due to misalignment of the bone fragments. However, the rigidity of the screw, geometry of the fractured anatomy (e.g., femur and pelvis), and osteoporosis may cause an array of complications. To address these challenges, we propose the use of a continuum manipulator and a bendable medical screw (BMS) to drill curved tunnels and fixate the bone fragments. This novel approach provides the clinicians with a degree of freedom in selecting the drilling entry point as well as the navigation of drill in complex anatomical and osteoporotic bones. This technique can also facilitate the treatment of osteonecrosis and augmentation of the hip to prevent osteoporotic fractures. In this paper: (1) we evaluated the performance of the curved drilling technique on human cadaveric specimens by making several curved tunnels with different curvatures and (2) we also demonstrated the feasibility of internal fixation using the BMS versus a rigid straight screw by performing finite element simulation of fracture fixation in an osteoporotic femur.

We present an autonomous manipulation approach for tissues with anisotropic deformation behavior using a continuum manipulator. The key feature of our visionbased study is an online learning and estimation method, which makes its implementation independent of any prior knowledge about (i) the deformation behavior of the tissue and (ii) continuum manipulator as well as (iii) calibration of the vision system with respect to the robot. This important feature addresses the difficulty of using model-based control approaches in deformation control of a continuum manipulator manipulating an unknown deformable tissue. We evaluated the performance and robustness of our method in three different experiments using the da Vinci Research Kit coupled with a 5 mm instrument that has a 4-degree-of-freedom snake-like wrist. These experiments simulated situations that occur in various surgical schemes and verified the adaptability, learning capability, and accuracy of the proposed method.

This article presents the development and experimental evaluation of a redundant robotic system for the less-invasive treatment of osteolysis (bone degradation) behind the acetabular implant during total hip replacement revision surgery. The system comprises a rigid-link positioning robot and a continuum dexterous manipulator (CDM) equipped with highly flexible debriding tools and a fiber Bragg grating (FBG) based sensor. The robot and the continuum manipulator are controlled concurrently via an optimization-based framework using the tip position estimation (TPE) from the FBG sensor as feedback. Performance of the system is evaluated on a setup that consists of an acetabular cup and saw-bone phantom simulating the bone behind the cup. Experiments consist of performing the surgical procedure on the simulated phantom setup. CDM TPE using FBGs, target location placement, cutting performance, and the concurrent control algorithm capability in achieving the desired tasks are evaluated. Mean and standard deviation of the CDM TPE from the FBG sensor and the robotic system are 0.50 and 0.18 mm, respectively. Using the developed surgical system, accurate positioning and successful cutting of desired straight-line and curvilinear paths on saw-bone phantoms behind the cup with different densities are demonstrated. Compared to the conventional rigid tools, the workspace reach behind the acetabular cup is 2.47 times greater when using the developed robotic system.

We present a generic data-driven method to address the problem of manipulating a three-dimensional (3-D) compliant object (CO) with heterogeneous physical properties in the presence of unknown disturbances. In this study, we do not assume a prior knowledge about the deformation behavior of the CO and type of the disturbance (e.g., internal or external). We also do not impose any constraints on the CO's physical properties (e.g., shape, mass, and stiffness). The proposed optimal iterative algorithm incorporates the provided visual feedback data to simultaneously learn and estimate the deformation behavior of the CO in order to accomplish the desired control objective. To demonstrate the capabilities and robustness of our algorithm, we fabricated two novel heterogeneous compliant phantoms and performed experiments on the da Vinci Research Kit. Experimental results demonstrated the adaptivity, robustness, and accuracy of the proposed method and, therefore, its suitability for a variety of medical and industrial applications involving CO manipulation.

Since the da Vinci surgical system was approved by the Food and Drug Administration (FDA) in 2000, the development and deployment of various robot-assisted minimally invasive surgery (MIS) systems have been largely expedited and boomed. With the rapid advancement of robotic techniques in recent decades, robot-assisted systems have been widely used in various surgeries including orthopedics. These robot-related techniques are transforming the conventional ways to conduct surgical procedures. Robot-assisted orthopedic surgeries have become more and more popular due to their potential benefits of increased accuracy and precision in surgical outcomes, enhanced reproducibility, reduced technical variability, decreased pain, and faster recovery time. In this paper, robotic systems and navigation techniques in typical orthopedic surgeries are reviewed, especially for arthroplasty. From the perspective of robotics and engineering, the systems and techniques are divided into two main categories, i.e., robotic systems (RSs), and computer-aided navigation systems (CANSs). The former is further divided into autonomous RS, hands-on RS, and teleoperated RS. For the latter, three key elements in CANS are introduced, including 3D modeling, registration, and navigation. Lastly, the potential advantages and disadvantages of the RS and CANS are summarized and discussed. Future perspectives on robotics in orthopedics, as well as the challenges, are presented.