Search results for "navigation systems"
showing 3 items of 3 documents
Visually Perceived Distance Judgments: Tablet-Based Augmented Reality Versus the Real World
2016
Does visually perceived distance differ when objects are viewed in augmented reality (AR), as opposed to the real world? What are the differences? These questions are theoretically interesting, and the answers are important for the development of many tablet- and phone-based AR applications, including mobile AR navigation systems. This article presents a thorough literature review of distance judgment experimental protocols, and results from several areas of perceptual psychology. In addition to distance judgments of real and virtual objects, this section also discusses previous work in measuring the geometry of virtual picture space and considers how this work might be relevant to tablet A…
Adaptive Control of Underactuated Underwater Vehicles
2008
This paper deals with a control strategy for underactuated underwater vehicles whose target is trajectory tracking. A cascade approach is employed which brings to a control law consisting of: a) an outer loop, obtained from the vehicle kinematic model, which forces this model to track the reference trajectory; b) an inner adaptive control loop which forces the system to track the reference signals given by the outer control loop. Conditions for asymptotic tracking of the trajectory and boundness of the unactuated velocities are given. Simulation tests illustrate the proposed approach.
Trajectory tracking of underactuated underwater vehicles
2003
This paper deals with a control strategies for underactuated underwater vehicles whose target is the tracking of a space trajectory. A cascade control strategy is employed which brings to a control law consisting of: 1) a kinematic control law, derived from the vehicle kinematic model, which forces this model to track the reference trajectory; and 2) a dynamic control law which forces the system to track the reference signals given by the kinematic control law. Conditions for asymptotic tracking of the trajectory are given with reference to the standard dynamical model of the above vehicle. An observer of the marine current is also added in order to process the control law. Simulation tests…