Victor J. Gonzalez-Villela

The Use of Aerial Images and GPS for Mobile Robot Waypoint Navigation

The application of aerial and satellite imagery for mobile robot path planning and navigation has shown potential in recent years. Their uses vary from identifying terrain properties for creating traversability maps to extracting landmarks for autonomous navigation. With the freely available differential positioning system, Wide Area Augmentation System (WAAS)/European Geostationary Navigation Overlay Service (EGNOS), the use of the GPS with aerial images providing valuable contextual data demonstrates potential in waypoint-based navigation of mobile robots. However, important issues relating to the spatial accuracies of image, waypoint, and GPS-derived data, vital for obtaining accurate navigation results, are often overseen. This paper defines the causes of spatial inaccuracies in order to develop optimal waypoint navigation parameters and provides researchers with sufficient knowledge to reproduce similar results. An improvement of up to 48% in the number of waypoints reached, depending on the radius, was determined for the positional correction of the GPS. The results are shown with a simulated synchronous drive robot in Matlabs Simulink environment. The reader is presented with a method for easily creating waypoints from aerial images, yielding results to a similar level of accuracy to conventional and often tedious manual methods.

Hydraulic Balance Ring Study and Design Using Optical Techniques

A new approach to understand factors that affect self-balancing devices is proposed. Experimentation was conducted to determine the influence of different factors on the performance of an automatic washing machine hydraulic balance ring fluid during transient and steady states. Two different optical techniques were used: one for visualization (high-speed photography) and another for velocity field measurement (Particle Image Velocimetry, PIV). Results were used to build a new balancer design and compared with previous findings. Important factors in balancer design were deducted.Copyright

Kinematics and Tip-Over Stability Analysis for a Hybrid Serial-Parallel Mobile Manipulator

This paper shows the geometry and the kinematical model for a compounded serial-parallel wheeled mobile manipulator. The parallel manipulator, Stewart Platform, is an interface that helps the whole system to accomplish stable motion when handling heavy objects and to improve mobility over uneven-terrain by repositioning their center of mass. To evaluate the possibility of tip over, a stability analysis is performed; some criteria are established. Computer simulations and experiments are carried out and the influences of different robotic postures on the tip-over stability are analyzed through simulation results.Copyright

Experimental Vehicle That Avoids Collisions Through Steer by Wire and Differential Drive Systems

The implementation of Drive-by-Wire systems is increasing due to their advantages. One of these advantages is the capability to be autonomous or semiautonomous. This paper investigates the collisions avoidance in a Steer-by-Wire and Differential Drive experimental vehicle. The Steer-by-Wire system is tested using the Ackerman formulation. Ackerman equations are modified in order to vary the vehicle’s steering ratio in function of the vehicle’s speed. As a result, better high speed vehicle’s control is achieved. The collision avoidance system works using infrared sensors around the vehicle, avoiding frontal and lateral collision. The distance to the obstacles is the parameter selected to avoid collisions (leaving the time for other actions like warnings to the driver). The fusion of the Autonomous Steer-by-Wire and the collisions avoidance system develops a semi-autonomous vehicle. This vehicle avoids collisions automatically, even if the driver does not avoid the collisions by himself, greatly reducing the probability of accidents.Copyright

5 DOF Instrumented Master Device for Experimental Understanding of Intuitive Teleoperation

Teleoperation it is a modern challenge within the areas of mechatronics, e.g. precision mechanics, control electronics, computational algorithms. Teleoperation arose from the necessity of handling nuclear material, but in recent years has come essential in others activities such as the space or undersea exploration, mobile robotics, medical applications and entertainment. The main goal in this work is to study the “operation at a distance,” with a master-slave system, to define the concept of “Intuitive Teleoperation,” like a novel approach to perform semiautonomous teleoperation, based on incomplete information from the environment, objects and system. In this level of the investigation the experimentation was realized with a 5 DOF anthropomorphic device (master device) that acquired data of the movements from a human operator, which was sent to a 5 DOF anthropomorphic robot (slave device). Both, direct kinematics (over the master device) and inverse kinematics (over the slave device) were used to calculate their space parameters (point coordinates, orientation) and to implement intuitive algorithms. Has been observed that the master device movements are followed and enhanced by the slave subsystem when the intuitive algorithms are activated. Semiautonomous teleoperation was achieved using a 5 DOF instrumented master device. The experiments enhanced the “operation at a distance” by defining an intuitive algorithm.Copyright

UNAM’s University-Industry PhD Engineering Program

This article presents UNAM’s University-Industry PhD Engineering Program that has been implemented over the last six years to help in the training of young researchers. The program expands along 8 semesters and is strengthened by the Mexican Science and Techology’s (CONACYT’s) funding schemes. Specifically, CONACYT’s new “Funds for Innovation Scheme”, which is intended for corporations that wish to design and develop new products, processes or services. The paper reports on the activities typically carried out by a research student (RS) in each of the 8 semesters and presents the results obtained in the PhD research work titled “Design and Development of a PVC Ampoule Filler-Sealer Machine System”.© 2010 ASME