A novel 6-Degree-of-Freedom (DoF) hybrid haptic device is presented in this paper. Hybrid mechanism consists of parallel kinematic structure, R-CUBE and a 3-DoF orientation mechanism. In our previous study, the original configuration of the R-CUBE mechanism was investigated. In this work, the original design of R-CUBE is reconfigured as a haptic mechanism and the final mechanism is reoriented in order to equally distribute the gravitational effects to all grounded actuators. Rotational motions of the end-effector are monitored through the 3-DoF orientation mechanism placed on the moving platform of the parallel platform. The design of this haptic device is suitable to reflect forces in translational motions, thus point-type of contact is available for this system. The designed device is manufactured utilizing various types of manufacturing processes, such as wire erosion, laser cutting, milling and turning. Finally manufactured mechanism is integrated with electromechanical components and tested for manipulability.

Abstract-Haptics technology has increased the precision and telepresence of the teleoperation and precision of the in-house robotic applications by force and surface information feedback. Force feedback is achieved through sending back the pressure and force information via a haptic device as the information is created or measured at the point of interest. In order to configure such a system, design, analysis and production processes of a haptic device, which is suitable for that specific application, becomes important. Today, haptic devices find use in assistive surgical robotics and most of the teleoperation systems. These devices are also extensively utilized in simulators to train medical and military personnel. The objective of this work is to design a haptic device with a new structure that has the potential to increase the precision of the robotic operation. Thus, literature is reviewed and possible robot manipulator designs are investigated to increase the precision in haptics applications. As a result of the investigations, conceptual designs are developed. Ultimately, final design is selected and produced after it is investigated in computer-aided-design (CAD) environment and its kinematic and structural analyses are carried out.

In this paper, the problem of function generation synthesis of planar 5R mechanism is studied using the least squares approximation method with equal spacing of the design points. The study represents a case study for analytical function generation of multi-degrees-of-freedom systems. The planar 5R mechanism is designed with a fixed input joint and a moving input joint adjacent to the first input, whereas the remaining fixed joint is the output joint. The input/output relationship of the mechanism is expreseed as an objective function in polynomial form with four unknown construction parameters. . The objective function involves nonlinearities, however the problem is linearized using Lagrange variables. The linear system is solved and finally the construction parameters of the mechanism are determined. A numerical example is presented as a case study.

Initial calibration tests of a novel hybrid-structured kinesthetic haptic device based on an R-CUBE mechanism is presented in this paper. Experimental validation of the kinematics along with the experimental test set-up description is provided for the manufactured R-CUBE mechanism.

The Chebyshev approximation is well known to be applicable for the approximation of single input-single output functions by means of a function generator mechanism. The approximation method may be also applied to multi-input functions, although until recently, it was not used for function generation with multi-degrees-of-freedom mechanisms. In a recent study, the authors applied the approximation method to a two-degrees-of-freedom mechanism for the first time, however the selection and iteration of the design points at which the errors were minimized was not satisfactory. In this study, an alternative method of selection and iteration for these design points is introduced and the corresponding spacing is called the "regional spacing". As a case study for the application of the approximation of multi-input functions, a spherical 5R mechanism is used to generate a two input-single-output function. The input joints of the mechanism are selected as one of the fixed joints and the moving mid-joint, whereas the remaining fixed joint represents the output. The synthesis problem is analytically formulated and presented in polynomial form for five and six unknown parameters. The synthesis problem for five unknown parameters is illustrated as a numerical example. Regional spacing is used for the selection and iteration of design points for the synthesis. The Chebyshev approximation along with the Remez algorithm is utilized to find the unknown construction parameters and the error of the function. The design points and the coefficients of the approximation polynomial are determined by numerical iteration using six moving points. At each iteration step, the design points are relocated at the extremum error points in their respective regions. Iterations are repeated until the magnitudes of the extremum point errors are approximately equal. Finally, the construction parameters of the mechanism are determined and the variation of the percentage error between the desired and generated function values is obtained.