An active protection system (APS) provides military vehicles with automatic rapid-response protection from inbound armour penetrators. An APS suite includes sensors to detect threats, high-speed fire control processing and countermeasures to neutralise threats. To be successful, APS typically must sense, classify and eliminate threats in a fraction of a second. The development of an effective APS requires the ongoing participation of industry, and the vision, resources and scale of the sponsor required to achieve the desired end state.

Traditionally, anti-armour direct fire threats have been addressed by simply adding more heavy armour. The weight burden of this added survivability now steers decision-makers to seriously consider the lighter weight and highly capable modern APS technologies. They are lighter than equivalent armour upgrades and their sensors provide valuable situational awareness. This approach would optimise protection using a mix of traditional armour and APS.

Without a modular approach, the upgrade of an APS to protect against new and changing threats relies almost exclusively on the vendors for proprietary modifications, which is potentially an expensive and time-consuming process.

Modular APS (MAPS) takes APS technology a step further by providing a modular framework and controller that implement approved government and industry standards and interfaces, allowing interchangeable APS subsystem components. This modular approach creates additional value for the government and drives competition for best-of-breed technologies.

The lack of formal system requirements has been a perpetual challenge for APS development. With that in mind, the US Army’s overarching strategy now includes expedited characterisation of existing capabilities to guide requirements and user preference for our modular approach.

The expedited APS (ExAPS) programme is investigating the installation of APS on to various platforms in the current fleet. The results of these characterisations are guiding the development of MAPS.

MAPS is a multi-year research, development and engineering command (RDECOM)-wide effort led by the Detroit Arsenal-based US Army Tank Automotive Research, Development and Engineering Center (TARDEC), and done in collaboration with the acquisition community and industry. MAPS delivers an enduring framework and controller, which provides the quickest path to an APS that is modular, upgradable and safety-compliant for ground vehicles across the fleet. Ultimately, MAPS will enable state-of-the-art protection to save the lives of warfighters. A prototype controller is being used to verify interfaces, deterministic communications protocols and performance requirements with the objective long-term MAPS controller (MAC) design and build activities running in parallel. This prototype controller is being used for the FY17 MAPS soft-kill demonstrator (SKD) effort while the MAC is being developed. Development of the framework and controller has matured to the point that initial MAC products will be available in 2017. Also, work with industry partners to develop and demonstrate MAPScompliant solutions with the MAC by 2018 is already under way. The controller prototype effort has enabled integration of MAPS framework (MAF)-compliant subsystems, and the lessons learned have been fed into development of the MAC.

The methodology

MAPS uses model-based systems engineering (MBSE) processes and methods, which has required a tremendous initial investment of time and talent. We consider this a worthwhile investment to build a robust foundation that will continue to be refined rapidly using the programme’s capability demonstrations. The MBSE process allows us to define system and subsystem specifications in a highly efficient manner that includes the necessary traceability requirement. Once the MBSE model is in place, it can be modified and reconfigured rapidly. Unlike some traditional systems engineering efforts that remain fairly abstract, the safety criticality associated with APS requires a great deal of detail in the model to assure that future MAPSbased APS are able to satisfy safety board requirements in order to field the technology. Achieving a fully safety-board-compliant design is one of the primary objectives of the MAPS programme. Obtaining safety compliance in a modular manner is optimal, diminishing the investment needed for future system certifications and minimising the time required to certify enhancements or new capabilities.

A MAPS community of interest (COI) has been established to enable collaboration with prospective subsystem developers throughout the development of the framework. The goal is to leverage the broadest possible participation of government and industry subject matter experts (SMEs) to help shape the right long-term solution for the US Army. The MAPS team provides periodic framework knowledge point updates on progress to date in order to facilitate members’ active contribution to the MAPS framework development process and ensure consistent communication. Based on the success of this group and the interest of external contributors, the MAPS team is in the process of rolling out an international subgroup COI to facilitate direct conversation with non-US developers by the end of 2017.

Building MAPS based on decades of relevant APS experimentation provides a perspective that has been advantageous in guiding the desired technologies to transition in the short and long term. Engaging SMEs across the US Army and working with industry partners has provided additional clarity for the initial MAPS capability. This approach has also helped identify an efficient way ahead for future upgrades that can be worked in parallel using government funding or industry-independent R&D (IRAD), and created new opportunities to enter into cooperative R&D agreements (CRADAs).

Whether designing a traditional or modular APS, the capability developer must carefully consider the economic exchange of the dilemma they are presenting to the enemy, as well as the cost to rapidly upgrade APS to tackle new and evolving threats. For example, General David G Perkins, commanding general, US Army Training and Doctrine Command, noted at the Association of the US Army’s Global Force symposium in March 2017 that while our ally’s use of Patriot missiles to defeat an unmanned aerial vehicle (UAV) was effective, it may not represent a good economic exchange ratio. This perspective points to the importance of considering the value proposition that the initial MAPS-based APS provides to the platform that it’s protecting, as well as planned future upgrades. From an operations perspective, the cost of defeat (countermeasures and recalibration), as well as the time to reset are clear measures of interest.

How the value proposition will progress is less clear and, likely, platform-dependent. Will it focus on lower operating costs, broader threat defeat, or both?

Advantages of modularity

Under Secretary of Defense for Acquisition, Technology and Logistics Frank Kendall presented the white paper ‘Better Buying Power 3.0’ in 2014. The paper focused on technology, affordability, and open systems design and architecture. He stressed the goal of acquisition, and science and technology (S&T) communities to achieve affordable programmes moving forward. RDECOM and TARDEC are applying the concepts from ‘Better Buying Power 3.0’ to the MAPS programme. The army has long recognised the value of establishing a sound capability and performance technology baseline, but it is now focused on the ability to adapt and perform in an uncertain future. The requirements driving MAPS will help the army focus future S&T investments on specific technology gaps and affordability while avoiding vendor lock.

The Army Operating Concept (AOC) tells us the future battlefield is unknown and unknowable; the enemy is frequently observed modifying and adapting their tactics, and our government procurement process needs the flexibility to keep up. This problem underscores the need to provide a framework that allows various platforms to rapidly accept new capabilities in order to keep pace with evolving threats in a safe and reliable manner. The MAPS approach is capable of producing the needed spiral upgrades with new software or subsystems in a timetable that is relevant to the given conflict.

The fielding of APS capabilities in quantity will create new business opportunities for industry. Once the magnitude of these opportunities is understood, a competitive marketplace will advance capabilities and prevent vendor lock, ensuring the government maximises its resources. A modular approach will enable new industry partners entering the APS ecosystem to bring their disruptive technology to a transition-ready status with efficient reuse of the central MAPS architectural elements. While we already understand the path to a modular end state, it will take time for dominant supporting technology positions to emerge.

It’s clear that prototyping in a modular fashion reduces the impact of new technology insertion. We must be prepared to rapidly surge and scale up new capabilities when we are faced with the next war. It will take time and resources to develop a firm understanding of what an enduring architecture and central elements are required to do, but leaning forward with a modular approach allows the right solution to emerge naturally. Attempting to implement a modular approach while in a vendor-locked state would add many complications that may never be overcome. Additionally, rapid prototyping with MAPS helps our supply base and gives our leaders options that can be rapidly transitioned. While we don’t understand all of the challenges we will face tomorrow, we do know that they will be different than today’s.

APS industry partners that invested IRAD resources to stay relevant benefitted when the army began seeking mature capabilities and this will continue to be the case with the MAPS approach. Industry partners should consider spending on IRAD for viability; if they do not, they risk falling behind. IRAD opportunities will include interoperability challenges in terms of protection volumes for convoys and vehicle formations, as well as deconflicting interference with other technologies on the platforms. Army leaders expect future MAPS capabilities to unburden the soldier, increase platform lethality (through increased situational awareness in terms of time to respond and accuracy) and result in a capability shift from surviving the engagement to safely completing the mission in an offensive posture.

A modular approach built on standardised interfaces and architecture ensures that the government has the best-value solutions for a given set of requirements at any time. While it’s hard to envision what the end state will be in terms of specific fielded technologies, it is clear that MAPS will be a disruptive element on the battlefield.

The way ahead

MAPS is the foundation of the US Army’s overarching APS strategy. It enables the integration of APS to provide protection from advanced threats at an optimised weight, facilitates transition with commonality across the vehicle fleet and allows APS to be tailored to meet specific needs. Regardless of approach, requirements have to be articulated and planned for, and a modular approach will facilitate the needed competition at the subsystem level. It is worth noting that APS introduces new dimensions for protection-based requirements, and clarity is being achieved in terms of what ‘best value’ represents for these new capability dimensions. MAPS provides best-of-breed subsystem flexibility and competition, and an avenue for technology insertion from industry and government S&T communities. It is designed to enhance safety and shorten transition times. The US is also planning for transition to programmes of record and the corresponding contracting/acquisition approach to obtain MAPS capabilities.