PURPOSE
SMF/M is the top-of-the-line photometric instrument among the ones available at the market designed for lighting equipment. The system is based on the advanced technologies in the field of localization within the accuracy of less than 1 m, and uses a coordinate comparison module capable of combining and integrating all position signals received from GPS SBAS, odometer, accelerometers, compass, and light finder optoelectronic sensor. 13 photometric sensors of the measuring bar capture a light beam in optimal measuring positions. Restoration methods necessary for obtaining an isolux diagram for nodal points according to ICAO, allow of calculating and correcting guidance errors. The overall database allows of keeping all measurement data received from several airports. The system is equipped with an optical guidance camera and a sound unit. All aspects necessary for easy and convenient field photometric measurements are taken into account.
OPERATING CONCEPT
Operation of SMF/M is based on the principle of movement of the measuring bar along the measured light line (or in parallel with the line). The SMF/M measuring bar is installed perpendicular to the light line and thus it can cross the radiated light beam in its base portion when the bar is over a distance from the light, and in its upper points as it approaches to the light.
Generation of ICAO point grid is performed by means of routine simulation on the basis of discrete measurement results obtained during movement of measuring bar between the current measured light and the next nearest one.
The measuring bar contains 13 light sensors and 2 color sensors according to CIE 1931 located above the bar in order to obtain the best resolution-distance ratio. The measuring bar also includes a special head, containing 2 fixed light position sensors as well as a guidance camera.
The scanning rate is determined by a movement speed rather than measurement time, therefore the system does not depend on a movement speed, and the driver can stop the car equipped with the SMF/M system if necessary and then move on without affecting the measurement results.
The SMF/M system records data every 10 cm of distance covered using a high-resolution odometer (1 pulse per every 0.7 mm).
The SMF/M system can make calculations on the basis of a large volume of data which enables accuracy and error parameters necessary for the assigned task. A user can direct the autocar accurately with the help of a guidance camera showing a current location of the measuring bar relative to the ideal line of movement.
The obtained data of the ICAO point grid for all measured lights are processed and saved in a system data base. A user can analyze all data relevant to the parameters of a separate light or the lights of entire lighting system. Photometric data are presented in a tabulated form or diagrammatically including isocandela diagrams according to the ICAO requirements.