TY - THES ID - 148636334 TI - Master thesis : Development of a speed measurement interface for projectiles and moving parts and accuracy analysis of these measurements AU - Jacoby, Jonathan AU - Vanderbemden, Philippe AU - Boigelot, Bernard AU - Vanderheyden, Benoît AU - Libotte, Hugues PY - 2017 PB - Liège Université de Liège (ULiège) DB - UniCat KW - sensor KW - microcontroller KW - speed measurement interface for projectiles KW - accuracy analysis KW - speed measurement of moving parts inside FN MAG machine gun KW - counting module KW - Ingénierie, informatique & technologie > Ingénierie électrique & électronique UR - https://www.unicat.be/uniCat?func=search&query=sysid:148636334 AB - FN Herstal has developed for many years metrological systems specially dedicated to the gunsmith business. Among these, we will focus on speed measurement devices dedicated to projectiles and moving parts. These measurements are carried out either during the development phase, for the creation of new products, or during the production phase, in order to ensure the tuning and the quality control of the products.
The first task I needed to accomplish was the entire development, from the hardware to the software, of a counting module whose main purpose is measuring a time separating two events. I was able to build a completely functional prototype, mounted on a pre-drilled board, with a microcontroller coded in C, and equipped with the necessary interface. In addition, all customer requirements were met.
One of the applications of this module was the measurement of the average speed of a projectile, which transits through two existing speed barriers, outputting a digital signal triggered by the transit of the projectile. Once plugged to the built module, the projectile speed is correctly computed. The created module is also able to detect every possible defect that could be caused by the speed barriers.
An accuracy analysis, taking the form of an uncertainty budget of the whole package, speed barriers and counting module, was carried out. The uncertainty of the measurement is now accurately estimate and all major contributions of the error have been identified.
The last challenge was to develop a device which measures the average speed of the moving parts, inside a FN MAG machine gun, when these moving parts are going backwards (from the barrel to the butt). The prototype relies on a sensing method based on magnetic flux detection with strong magnets and Hall probes. ER -