Search results for "Automation"

Hazards That Can Affect CNC Machine Tools during Operation—An AHP Approach

2020

CNC (computer numerically controlled) machine tools are highly advanced technological systems, used to machine parts by means of metal cutting processes. Their structure and kinematics are very complex, involving accurate coordinated motions on three to five axes. Operating CNC machine tools is a complicated process, which can easily be affected by errors. Nowadays, safety systems and devices are developed in order to make this process safer and more user friendly. Modern CNC controllers are designed to deal with obvious sources of hazards, such as overloads (by means of various sensor systems) and collisions (by checking the NC code syntax and simulating it on the machine). However, despit…

Interactive simulation of one-dimensional flexible parts

2006

Computer simulations play an ever growing role for the development of automotive products. Assembly simulation, as well as many other processes, are used systematically even before the first physical prototype of a vehicle is built in order to check whether particular components can be assembled easily or whether another part is in the way. Usually, this kind of simulation is limited to rigid bodies. However, a vehicle contains a multitude of flexible parts of various types: cables, hoses, carpets, seat surfaces, insulations, weatherstrips... Since most of the problems using these simulations concern one-dimensional components and since an intuitive tool for cable routing is still needed, w…

From the Editor in Chief: Humans and their technologies play the infinite game

2019

Complex objects modeling: An entity-relationship approach

1989

Facilities for complex object modeling are nowadays needed in several areas of database applications (CAD/CAM, office automation, robotics, ...). Consequently, either new models are developed, or existing ones are extended to better respond to this requirement. Current proposals in the latter category are mainly based on the relational approach (with, as major outcome, the NF2 family of models) or on functional models like DAPLEX. This paper intends to show that the entity-relationship approach may secure an equivalent result, preserving the well known advantages inherent to this approach : increased readability and graphical display of the database schema.

Hybrid nonlinear observer for Inertial Navigation

2016

This paper considers the problem of designing an observer for navigation and localization of inertial systems. Since the measurement systems used in this field have a low update rate with respect to the control algorithm, the design of a suitable observer with sampled measurements is required. Here a hybrid non-linear observer is proposed, combining two different observers with different characteristics. A theoretical treatment is given in order to prove the convergence of the observer and it will be contextualized in the framework of the hybrid systems, providing an elegant setting for the proposed solution. Finally experimental results show the feasibility of the proposed observer and the…

An MDE Approach for Rapid Prototyping and Implementation of Dynamic Reconfigurable Systems

2015

This article presents a co-design methodology based on RecoMARTE, an extension to the well-known UML MARTE profile, which is used for the specification and automatic generation of Dynamic and Partially Reconfigurable Systems-on-Chip (DRSoC). This endeavor is part of a larger framework in which Model-Driven Engineering (MDE) techniques are extensively used for modeling and via model transformations, generating executable models, which are exploited by implementation tools to create reconfigurable systems. More specifically, the methodological aspects presented in this article are concerned with expediting the conception and implementation of the hardware platform and the integration of corre…

Visual Servoing Based on Shifted Moments

2015

Over the past decade, image moments have been exploited in several visual servoing schemes for their ability to represent object regions, objects defined by contours or a set of discrete points. Moments have also been useful to achieve control decoupling properties and to choose a minimal number of features to control the whole degrees of freedom (DOFs) of a camera. However, the choice of moment-based features to control the rotational motions around the $x$ -axis and $y$ -axis simultaneously with the translational motions along the same axis remains a key issue. In this paper, we introduce new visual features computed from low-order “shifted moments invariant.” Importantly, they allow us 1…

Experimental design method to the weld bead geometry optimization for hybrid laser-MAG welding in a narrow chamfer configuration

2017

International audience; The work presented in this paper relates to the optimization of operating parameters of the welding by the experimental design approach. The welding process used is the hybrid laser-MAG welding, which consists in combining a laser beam with an MAG torch, to increase the productivity and reliability of the chamfer filling operation in several passes over the entire height of the chamfer. Each pass, providing 2 mm deposited metal and must provide sufficient lateral penetration of about 0.2 mm. The experimental design method has been used in order to estimate the operating parameters effects and their interactions on the lateral penetration on one hand, and to provide a…

Wavefront holoscopy: application of digital in-line holography for the inspection of engraved marks in progressive addition lenses

2014

Progressive addition lenses (PALs) are engraved with permanent marks at standardized locations in order to guarantee correct centering and alignment throughout the manufacturing and mounting processes. Out of the production line, engraved marks provide useful information about the PAL as well as act as locator marks to re-ink again the removable marks. Even though those marks should be visible by simple visual inspection with the naked eye, engraving marks are often faint and weak, obscured by scratches, and partially occluded and difficult to recognize on tinted or antireflection-coated lenses. Here, we present an extremely simple optical device (named as wavefront holoscope) for visualiza…

Robot Retrofitting by Using LinuxCNC Complemented with Arduino/RaspberryPI

2020

The use of robots for any manufacturing process is present in almost every industry nowadays. Nevertheless, automating the manufacturing process has always been a challenge for every one of them due to costs and complexity of adding this kind of automation. Acquiring robotic equipment in a concentrated market where the vendors have locked-in their clients can be expensive. In addition to this, the development of intern-factory made solutions has a very steep learning curve and it is not easily achievable. Due to these barriers small and medium size players can’t easily jump into this revolution.