Low cost, high strength electronics module for airborne object

#The present invention relates generally to electronics modules and, more particularly, to embodiments of a low cost, high strength electronics module for deployment onboard an airborne object, such as an airborne munition.

#Airborne munitions of increasingly-smaller sizes are being equipped with electronics modules to provide precision guidance and other functionalities. When deployed aboard an airborne munition, and especially when deployed aboard a smaller airborne munition, such as a guided projectile, it is desirable for the electronics module to be relatively compact and lightweight. It is also desirable for the electronics module to operate reliably even when subjected to extreme forces resulting from, for example, projectile launch or projectile spin; e.g., an electronics module deployed within a gun-fired projectile may experience upwards of 20,000 g-forces during firing, and, during flight, may spin at a rotation rate approaching or exceeding 150 revolutions per second. Munition-deployed electronics modules commonly include a plurality of printed circuit boards (PCBs) arranged in a stacked configuration (referred to herein as the “PCB stack”) to accommodate the unique geometric shape of the munition shell, which may include successive cylindrical and conical sections of varying diameters. A number of support structures, such as a tray, a slide, a cage, and the like, are typically utilized to space the PCBs apart along the longitudinal axis of the munition and to provide structural support for the PCBs in the PCB stack. Electrical interconnections are typically formed between neighboring PCBs utilizing specialized connectors, such as miniaturized connectors or flex cables.

#Although relatively rugged and compact, PCB stacks of the type described above are limited in certain respects. The support structures utilized to space neighboring PCBs in conventional PCB stacks increase the overall weight and cost of the airborne munition and reduce available space within the munition shell. As a further disadvantage, the specialized connectors utilized to interconnect neighboring PCBs in the PCB stack are also relatively costly to acquire. More importantly, the installation of such specialized connectors is generally not amenable to automated manufacturing processes and consequently incurs considerable manual labor costs during low or high volume fabrication. As a still further disadvantage, specialized connectors tend to occupy an undesirably large portion of the available surface area of PCBs that have been miniaturized for deployment aboard a projectile or other airborne munition.

#At least one example of the present invention will hereinafter be described in conjunction with the following figures, wherein like numerals denote like elements, and:

#FIG. 1 is an isometric view of an exemplary airborne object, namely, a precision guidance kit adapted to threadably mount to the nose of an artillery shell;

#FIGS. 2 and 3 are isometric and exploded views, respectively, of an electronics module deployed within the precision guidance kit shown in FIG. 1 in accordance with a first exemplary embodiment;

#The following Detailed Description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding Background or the following Detailed Description. While terms such as upper, lower, above, and beneath appear herein, these terms are utilized for convenience only and denote, for example, the relative positions of components when the airborne object (e.g., airborne munition) carrying the electronics module is pointing upwards, it should be clear that such components will reside in other relative spatial positions when the airborne object is repositioned, such as during flight and storage.

#FIG. 1 is an isometric view of an exemplary precision guidance kit (“PGK”) 10. PGK 10 includes a main body 12 having a threaded aft portion 14, a cylindrical housing section 16, and a conical housing section or nose 18. A spindle 20 (shown in phantom) is fixedly disposed inside cylindrical housing section 16, and a collar 22 is rotatably disposed around spindle 20. Collar 22 is adapted to rotate relative to main body 12 about the longitudinal axis of PGK 10 (represented in FIG. 1 by dashed line 24). PGK 10 further includes a pair of canards 26, which are mounted to collar 22 and rotate along therewith. Canards 26 normally reside in a non-deployed position and are released into a deployed position (shown in FIG. 1) after firing of PGK 10. During operation of PGK 10, collar 22 and canards 26 rotate in a rotational direction opposite that of main body 12 such that the position of canards 26 is generally fixed in inertial space (commonly referred to as a “roll control fixed canard configuration”) to increase guidance accuracy. Threaded aft portion 14 permits PGK 10 to be threadably mounted to the nose of an artillery shell or other projectile (not shown) in the place of a conventional fuse. In addition to providing a fusing function, PGK 10 also provides a precision guidance function during flight by manipulating the position of canards 26 in accordance with signals received from an onboard global positioning system (GPS) unit.

#To provide fusing, precision guidance, and other functionalities, PGK 10 is further equipped with an electronics module including a plurality of printed circuit boards (PCBs) disposed in a stacked configuration. In contrast to conventional PCB stacks wherein neighboring PCBs are electrically connected utilizing flex cables or other specialized connectors, embodiments of the electronics module further include one or more supportive interconnect structures, which electrically couple and axially space neighboring PCBs along the longitudinal axis of PGK 10. The supportive interconnect structures described herein also provide robust structural support of the PCBs in the PCB stack thus eliminating the need for trays, slides, cages, and other such structural systems typically utilized in conventional munition-deployed electronics modules.