Community Research and Development Information Service - CORDIS

Abstract

Over several years, CERCHAR has developed remote control and monitoring systems for mining machines. The operational range for radio control of shearers is of the order of a few tens of metres. Over larger distances, classical radio transmission techniques are inoperable or subject to unacceptable propagation problems created by the small size of the openings and the presence of massive metallic obstacles such as hydraulic roof support systems. CERCHAR has attempted to solve this problem by assuming longwalls and underground galleries to be oversized wave guides. Several in-situ experiments were conducted in test faces or in galleries to define frequencies best adapted to mine environments. A 300m effective transmission range was achieved in the cuvelette test mine of the Lorraine Collieries during tests conducted in a 4m x 2.5m gallery with metallic obstacles present. Diversity reception was shown to reduce image loss considerably. The quality of transmitted images was good, even within standard self-advancing roof support systems. Field tests of camera vision and recording were performed in realistic environmental conditions in underground mines, to evaluate the effect of dust and moisture on image quality. Visible as well as infra-red spectra were studied for localisation of mobile machines, and to detect automatically the presence of incoming personnel.

Additional information

Authors: VILLENEUVE DE JANTI P ET AL., CERCHAR, Groupe Electronique-Automatisme, Rueil-Malmaison (FR);SALZMANN H, U.S. Techniques, Division Amélioration des Matériels-Mécanisation (FR);DEGAUQUE P, USTLFA, Laboratoire de Radiopropagation (FR);DEVY M, CNRS, LAAS, Toulouse (FR);PAMPAGNIN L M, CNRS, LAAS, Toulouse (FR)
Bibliographic Reference: EUR 13442 FR (1991) 76 pp., MF, ECU 4, blow-up copy ECU 10
Availability: (2)
Record Number: 199110729 / Last updated on: 1994-12-02
Category: PUBLICATION
Original language: fr
Available languages: fr