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This paper presents a novel design of a threedegrees-of-freedom parallel manipulator. This manipulator has a crank arm type actuator instead of linear actuator, which is moved by means of servo motors. It has two degrees of orientation (Pitch and Roll) and one degree of translatory motion (Heave). Design is based on crank arm type actuator which can reduce the manufacturing cost without compromising on accuracy and precision. This paper develops an analytical method to analyze the basic kinematic equations of manipulator. Results are implemented using Matlab and are presented in graphical form; moreover Maplesoft MapleSim 6.1 was used for simulation purposes.

The research presented in this paper focuses on the development of a quasi-Linear Parameter Varying (qLPV) model for the XV-15 tiltrotor aircraft. The specific category of qLPV modeling technique, known as the model stitching technique, is employed to model the time-varying dynamics of XV-15 tiltrotor aircraft over the entire flight envelope. In this modeling approach, discrete linear state-space models are interpolated through lookup tables as function of scheduling parameters with the implementation of nonlinear equations of motion. The XV-15 qLPV model is configured with four scheduling parameters: altitude, nacelle incidence angle, wing flap angle and velocity. Additionally, a computational complexity analysis is presented. In particular, computational sensitivity of qLPV models configured with lookup tables to number of states and number of scheduling parameters is demonstrated. This is done to show the feasibility of real-time implementation of qLPV models with increasing fidelity (number of states) and expanding dynamic flight envelope (number of scheduling parameters).

A safe conversion of tiltrotor from helicopter mode to airplane mode is ensured through maneuvering within the conversion corridor, a constrained region in the airspeed versus nacelle angle graph. This paper presents preliminary work in the development of an automatic conversion maneuver. A high order quasi-Linear Parameter Varying model is developed for XV-15 that combines discrete state-space models to provide a varying model dynamics and trim characteristics during the conversion maneuver. Tracking control system based on gain scheduled linear quadratic tracker with integrator (LQTI) is designed for automatic conversion maneuver for XV-15 based on the qLPV model. Lastly, an optimization routine is performed to fly various conversion trajectories and identify optimal conversion maneuver.