THERMAL TARGETS


In the present electronic warfare scenario, where highly sophisticated, high resolution, broadband and multi-spectral imaging systems in visible, infrared and microwave have enhanced the lethality of all weapons systems, it has become necessary to provide better training tools for firing accuracy and testing of the weapons systems. To meet that goal DRDO has successfully developed the technology of thermal targets.

By utilising especially designed thermal targets, as reference targets in place of cost prohibitive real targets, the firing accuracy and efficiency of any weapon system or equipment fitted with thermal imaging system can be verified especially in the long ranges. The systems/equipment can then be fine tuned for optimal performance in the sets of specified battlefield environmental conditions. In addition, the most vital issues pertaining to the training of the weapon operators for target identification in night-time using thermal sight can also be addressed/tested.

These thermal targets provide high brightness index in the 3-5 m and 8-14 m wavelength region, in which most of the thermal imaging systems operate. These can be configured in any desired shape and size to generate 2-D and 3-D IR images. These thermal targets have performed successfully in all user trials related to MBT Arjun and Ajeya tanks. The night-time firing with thermal targets has been found to be far more accurate than day-time firing.

The aiming-type thermal targets developed by DRDO are made up of pixels/panels of variable size depending upon the users requirement. The pixels/panels comprise five layers of different materials sprayed/coated/pasted over each other. These panels are electrically heated by 12 V/120 AH batteries to obtain the required radiance. The resistive film uniformly spread over the Formica substrate, which in turn pasted over medium density fibre wood, is employed for generating heat. The thick film resistive coating is deposited by thermal spray process over Formica substrate. To avoid heat loss in backward direction, a highly insulating silicate pad is affixed over the medium density fibre substrate. To increase emission efficiency in forward direction, coating of a especially designed highly emission paint is applied over the resistive film. The topmost layer is a polymer coating transparent to IR in 8-14 m, imparting it the property of water resistance as well as scratch resistance.

The thermal targets can be used for accurate firing of antitank projectiles during night, hot spot generation of desired emittance, practice firing of heat seeking missiles (air-to-surface and surface-to-surface), field calibration of gray scales for IR images in target detection, recogni-tion, identification and ranging, and in thermal add-on devices.