Eventos Anais de eventos
CONEM 2022
XI Congresso Nacional de Engenharia Mecânica - CONEM 2022
Pose measurement of a parallel robot manipulator using augmented reality fiducial markers
Submission Author:
Leonardo Afonso Ferreira Bortoni , SC , Germany
Co-Authors:
Leonardo Afonso Ferreira Bortoni, Mauricio de Campos Porath, Lucas de Camargo Souza
Presenter: Leonardo Afonso Ferreira Bortoni
doi://10.26678/ABCM.CONEM2022.CON22-0449
Abstract
The control of robotic manipulators is a fundamental task to ensure accuracy and reliability of industrial processes. The real-time acquisition of high accurate pose- data of a manipulator, such as to enable online error correction, usually demands expansive equipment. In this work we explore the employment of augmented reality fiducial markers and a stereo digital camera as a low-cost alternative to track the pose of a Stewart platform. Three approaches were implemented and assessed. The first consists of obtaining the pose of the robot using just one fiducial marker. The second states the pose of a point amidst a plane generated by the position information from three markers. And the third repeats the last, adding a photogrammetry algorithm. Data fusion is implemented in the third scenario. Fiducial markers detection and computation is performed by the ArUco library, using the ROS environment coded in C++. The photogrammetry algorithm is implemented by means of the OpenCV library, also coded in C++. The stereo camera employed was a ZED2 model. Its intrinsic and extrinsic camera parameters are provided by the manufacturer. A robotic total station was employed in the frame calibration. The best strategy resulted in average positioning errors smaller than 1 millimeter, and orientation errors smaller than 0.2 degrees, with respect to the nominal pose stated by the previously calibrated Stewart platform.
Keywords
stewart platform, Fiducial Marker, Photogrammetry, Pose measurement
