1 Microcontroller based electronic modules for low velocity airburst Counter Defilade munitions Rakesh Nair School of Mechanical and Building Sciences Vellore Institute of Technology (VIT) - Chennai Campus Vandalur – Kelambakkam Road Chennai, Tamil Nadu, India -600 127 rakeshnair531@gmail.com G. Sakthivel School of Mechanical and Building Sciences Vellore Institute of Technology (VIT) - Chennai Campus Vandalur – Kelambakkam Road Chennai, Tamil Nadu, India – 600 127 sakthivel.g@vit.ac.in Hemanth Mithun Praveen School of Mechanical and Building Sciences Vellore Institute of Technology (VIT) - Chennai Campus Vandalur – Kelambakkam Road Chennai, Tamil Nadu, India -600 127 hemanth.mithun2013@vit.ac.in Abstract— Present counter defilade airburst weapon systems in defense sector make use of simple logic chips which are devoid of efficient inbuilt software safety that may cause accidental triggering of munitions. This paper deals with the design and development of microcontroller based electronic modules for counter defilade system for low velocity airburst munitions. The proposed design increases safety, cost efficiency and is highly feasible with existing weapons for infantry units. For system development, airburst analysis of munitions was investigated to theoretically determine the effect on target in defilade. A static rig testing of the entire system has also been performed to determine the response, triggering time and optimization of module design. Keywords - Logic chips, microcontroller, electronic modules, counter defilade systems, airburst munitions. I. INTRODUCTION Weapons have always been part of human struggle and their evolution. Weapons technology has made significant improvement in the last century and continues to do so. Recent developments in the warfare arena have introduced the world military to the difficulties of urban warfare. Assailants in open areas can be easily neutralized with line of sight engagement. The same is not possible while engaging an enemy behind cover or defilade where the target hit rate falls dramatically when using conventional weapons. This dire need led to the development of counter defilade systems that employ novel methods to neutralize targets behind cover. Conventional methods of counter defilade weapons include hand grenades. They are armed and thrown at defilade positions. After a delay ranging from 4-5 seconds, the grenade explodes clearing the region. Hand grenade’s effectiveness is limited to range of throw and timing [1]. It has a very high chance of inflicting friendly damage, if not properly handled. Hand thrown grenades were soon replaced with grenade the range of the weapon and is much safer, as the propelled grenade required a surface for impact before exploding. These systems are currently employed in battlefield to take out trenches and other enemy encampments. But the projectile is partly ineffective as a counter defilade weapon as it requires a hard surface to impact and detonate. This led to the development of field programmable counter defilade munitions. These systems can be attached to a conventional weapon [2] and use a logic chip based programmable fuse to detonate the propelled grenade at a fixed distance. The technology was extended to neutralize nearby targets by auto targeting systems using range optics and [3]. The air burst system to target infantry includes a grenade (normally 40 mm) with a fuse positioned near the explosive [4]. Figure 1. Airburst Counter defilade system operation.