Mobile robot vision system using continuous laser scanning for industrial application

Abstract

Purpose The purpose of this paper is the presentation and research of a novel robot vision system, which uses laser dynamic triangulation, to determine three-dimensional (3D) coordinates of an observed object. The previously used physical operation principle of discontinuous scanning method is substituted by continuous method. Thereby applications become possible that were previously limited by this discretization. Design/methodology/approach The previously used prototype No. 2, which uses stepping motors to realize a discontinuous laser scan, was substituted by the new developed prototype No. 3, which contains servomotors, to achieve a continuous laser scan. The new prototype possesses only half the width and turns out to be significantly smaller and therefore lighter than the old one. Furthermore, no transmissions are used, which reduce the systematic error of laser positioning and increase the system reliability. Findings By using a continuous laser scan method instead of discontinuous laser scan method, dead zones in the laser scanner field can be eliminated. Thereby, also by changing the physical operation principle, the implementation of applications is allowed, which previously was limited by the fixed step size or by the object distance under observation. By using servomotors instead of stepping motors, also a significant reduced positioning time can be accomplished maintaining the relative positioning error less than 1 per cent. Originality/value The originality is based on the substitution of the physical operation principle of discontinuous by continuous laser scan. The previously used stepping motors discretized the laser scanner field and thereby produced dead zones, where 3D coordinates cannot be detected. These stepping motors were substituted by servomotors to revoke these disadvantages and provide a continuous laser scan, where dead zones in the field of view get eliminated and the step response of the laser scanner accelerated.

Experimental image and range scanner datasets fusion in SHM for displacement detection

“…When the mirror starts spinning, the sensor “s” is synchronized when the origin generates a pulse indicating the 0° position and the starting of a cycle of 360° that finishes immediately before the “s” sensor generates the next beginning pulse. These pulses are used to calculate the scanning frequency and the zero reference, which is used to measure the angle where the light emitter source is positioned …”

“…These pulses are used to calculate the scanning frequency and the zero reference, which is used to measure the angle where the light emitter source is positioned. [6,54] The signal timing diagram in Figure 1b shows the starting pulse and the optoelectronic signal relation used to calculate the light emitted energy signal center position as described in the equations below. The period T 2π is the time for one motor revolution, defined as the time between two consecutive m 1 as in Equation 1, which are expressed by the code I 2π as defined in Equation 2.…”

Optimization of Abnormal Point Cloud Recognition in Robot Vision Grinding System Based on Multidimensional Improved Eigenvalue Method (MIEM)

“…Recently, many experts and scholars have carried out a lot of research on the identification of abnormal points obtained from the robot visual grinding system. Lindner et al [2] studied a novel robotic vision system that uses laser dynamic triangulation to determine the three-dimensional coordinates of an object of observation, thereby improving the applicability of the vision system. Wu et al [3] proposed a kind of footwear tracking method based on industrial robots.…”

Implementación digital de filtros FIR para la minimización del ruido óptico y optoelectrónico de un sistema de barrido óptico

“…El objetivo principal de esta investigación consiste en aportar una mejora a un sistema de barrido óptico, el cual fue patentado por la UNIVERSIDAD AUTÓNOMA DE BAJA CALIFORNIA, en el 2017 con el número de patente MX2014000647 (A). La mejora consiste en minimización del ruido óptico y optoelectrónico del sistema patentado para poder ser utilizado en condiciones ambientales con grandes intensidades de luz solar y otras fuentes luminosas, sin que su desempeño se vea perjudicado Lars Lindner et al, 2017;Lars Lindner et al, 2016;Miranda-Vega et al, 2018;Rodríguez-Quiñonez et al, 2017; Un aporte del presente artículo es la comparación de dichos filtros digitales para distintos tipos de fotosensores en un ambiente controlado, con fuentes de ruido que causan interferencia en el transductor del sistema OSS para simular condiciones a la que un sistema OSS está expuesto en un ambiente real de operación.…”