Defending Our Defenses: Luna is Developing Sensing and Analysis Tools to Reduce Missile Lifecycle Costs
During the time before deployment and usage, armaments (missiles, rockets, bombs) are placed in storage for long durations and exposed to a variety of environmental conditions during transportation. Training missions, in which armaments are loaded and unloaded from active aircraft, can expose them to the severe flight environment, stressing the systems’ electronics, structures, and payload. Throughout their lifecycles, missile systems may experience a multitude of environmental and physical effects that can induce degradation. Tracking individual missiles is a challenge, but knowing their history of environmental exposure and operational use is next to impossible. Two missiles of the same age could have very different use profiles and very different maintenance and sustainment needs.
Sensors exist that monitor some environmental effects on armaments, but due to power limitations none are currently able to remain operational for a full armament lifetime. Any system must be battery operated as there are no power supplies available in missile storage locations, so no sensors have been able to identify and log time spent in various states such as in storage or installed on aircraft. As long term exposure to harsh environments during storage and transportation can have significant negative effects on missiles, bombs, and other armaments, it has become critical to understand the full life-cycle exposure of in-service weapon systems. Rudimentary efforts at better understanding storage and handling conditions using small MEMS accelerometers have been attempted, but up to now there is no sensor system available that is able to track and identify the full profile of environments – in storage, on the flightline, on aircraft, or in the air – that would lead to more efficient sustainment through condition based maintenance.
Building on our extensive experience with low power sensing and wireless communication, Luna is currently developing a solution to track the environmental and physical parameters experienced by missile armaments in a form factor that is readily applicable to existing platforms. Luna’s system, known as ArmaLife™, will collect key environmental parameters and use this data to classify the missile as being in one of four states: indoor storage, ground transportation/handling, active/open storage, and flight.
ArmaLife: Lifecycle Monitoring for Improved Reliability, Maintainability, and Availability
The ArmaLife sensor will be small and low power with an integrated battery. It will be designed so it can be retrofit to the outside of an existing missile casing for rapid upgrading of current weapons. The sensor system will be used to monitor environmental factors experienced by the armament over its entire lifetime (at least 20 years) such as vibration, temperature, relative humidity, ultraviolet intensity, lux (ambient light) intensity, and barometric pressure. By combining these parameters using sensor fusion algorithms, the ArmaLife system will quantify the amount of time an armament has spent in indoor/outdoor storage, in transport, on a flightline, installed on a plane, or in flight (Figure 1). The system will be developed with extremely low power consumption components to ensure extended sensor lifetimes with limited power sources. The ArmaLife hardware will use small, reliable, inexpensive sensor designs to enable ease of integration into legacy and future armament systems.
In addition to recording armament status information and environmental exposure, the sensing system will categorize vibration events into low, intermediate, and high levels. To provide additional information for determining armament reliability, maintainability, and availability (RM&A), the sensing system will record min/max values and duration of environmental factors experienced by the missile. To make collected data easily accessible, the ArmaLife sensor system will use a radio frequency identification (RFID) transponder chip to monitor for a wake-up command from a maintainer, in turn initiating the transfer of collected data through wireless communications. The ArmaLife system is currently being engineered to be ultra-low profile for external armament integration, while not interfering with mechanical, electrical, or aerodynamic operation of the weapon.
ArmaLife Hardware and Targeted Data Analysis Will Lead to Better Condition Based Maintenance
The ability to monitor critical parameters and use them to classify armament status throughout the weapon system’s life-cycle will allow the Air Force to perform high efficiency condition based maintenance. The Air Force will be able to observe how long the armaments resides in each lifecycle stage, such as handling and transportation (Figure 2). Engineers and operators can then review exposure conditions and analyze what status and exposure effects have contributed to the current condition of their assets. The ArmaLife system will give the Air Force another data point in assessing missile reliability, maintainability, and availability for optimization of current maintenance schedules to effectively execute condition based maintenance.