Bilateral teleoperation has witnessed significant development since the mid-20th century, addressing challenges related to human presence in environments with constraints or a lack of skilled professionals. This article presents the kinematic and self-collision analyses of the quasi-spherical parallel manipulator, a three-legged parallel robot used as a haptic master device. The device is designed for remote center of motion-constrained operation in the telesurgical field. Inverse and forward kinematics are thoroughly analyzed to study working modes, singular configurations, and implement a haptic control architecture. The research explores the operative and reachable workspaces of the possible working modes, comparing them to find the most suitable one. Results highlight how the addition of the self-collision phenomenon impacts the working mode choice, drastically reducing most of the modes’ operative workspaces. An anti-collision control algorithm is finally introduced to maintain the architecture within its reachable workspace.

This paper focuses on developing a novel hybrid-haptic (nHH) device with a remote center of rotation with 4 DOFs (degrees of freedom) intendant to be used as a haptic device. The new architecture is composed of two chains handling each one a part of the motions. It has the advantages of a parallel robot as high stiffness and accuracy, and the large workspace of the serial robots. The optimal synthesis of the nHH was performed using real-coded genetic algorithms. The optimization criteria and constraints were established and successively formulated and solved using a mono-objective function. A validation and comparison study were performed between the spherical parallel manipulator and the nHH. The obtained results are promising since the nHH is compared to other similar task devices, such as spherical parallel manipulator, and presents a suitable kinematic performance with a task workspace free singularity inside.

This paper introduces a novel kinematic of a four degrees of freedom (DoFs) device based on Delta architecture. This new device is expected to be used as a haptic device for tele-operation applications. The challenging task was to obtain orientation DoFs from the Delta structure. A fourth leg is added to the Delta structure to convert translations into rotations and to provide translation of the handle. The fourth leg is linked to the base and to the moving platform by two universal joints. The architecture as well as the kinematic model of the new structure, called 4haptic, are presented. Comparisons in terms of kinematic behavior between the 4haptic device and the existing device developed based on spherical parallel manipulator architecture are presented. The results prove the improved behavior of the 4haptic device offering a singularity-free useful workspace, which makes it a suitable candidate to tele-operated system for Minimally Invasive Surgery. The dimensions of the 4haptic device, having the smallest workspace containing a prespecified region in space, are identified based on an optimal dimensional synthesis method.

This paper presents a new haptic device based on a parallel structure that can be used as a master interface in a teleoperation or haptic control architecture. The basic idea of a haptic device is to serve force and/or position reflection to the operator; at the same time that is being used by the human operator to input the required commands. The original mechanical structure of the presented system implies important advantages over other existing devices. The mechanism is a modification of the 6-d.o.f. Gough platform where the linear actuators have been replaced by cable-driven pantographs. Avoiding the use of reduction gears by means of cable transmission allows a wide sensing bandwidth. Some experimental indices comparing the performance of the presented device are presented. The paper shows the geometrical model and the kinematic analysis used on the control algorithms of this interface. The hardware and software architectures used on the system, and the control schemes implemented on a multi-axis board, are detailed. This setup provides an open control architecture that allows the implementation and experimentation of several bilateral control schemes. The integration of the haptic device in a teleoperation simulator is shown. This simulator includes virtual robotic slaves and its dynamic interaction with the virtual environment. Finally, the results obtained in the virtual objects manipulation experiments are shown. A classical force-position bilateral control scheme was used for these experiments.