What is SAPIENT? A Guide to the Open Standard for Sensor Integration

What is SAPIENT?

SAPIENT (Sensing for Asset Protection with Integrated Electronic Networked Technology) is an open standard developed by UK’s Defence Science and Technology Laboratory (DSTL).

It is designed to allow for a number of different devices (referred to in SAPIENT as edge nodes) to be integrated via plug-and-play connections to a single endpoint (referred to in SAPIENT as a fusion node).

This plug-and-play integration requires no prior knowledge of the specific devices serving as edge nodes, and the mechanism for control and information gathering is the same across device types, enabling faster, easier system setup.

The standard has undergone several revisions, including a switch to using Protobuf for sending all messages, rather than the previously used XML. Although this change is not backwards compatible, it has the advantage that as long as all points in the system have the correct set of Protobuf files, the messages will not be malformed.

SAPIENT is also focused on the messages being used to transmit processed information rather than raw data. This has the advantages of improving the autonomy of the contributing devices and reducing the overall system's bandwidth requirements.

The advantages of SAPIENT have led NATO to adopt it as a standard for counter-UAS systems under STANREC 4869.

Why is SAPIENT important?

SAPIENT has already been widely adopted in the counter-UAS space, which is a fast-moving part of the defence/security industry. It is also becoming more widely adopted in the broader defence space.  End users can mix sensors and effectors from different vendors without bespoke integration, enabling systems to be reconfigured rapidly as threats evolve.

With procurement requirements increasingly referencing SAPIENT, compliance avoids the risk of missing important business opportunities.  For prime contractors and system integrators, SAPIENT compliance is rapidly shifting from a differentiator to a baseline expectation, particularly on UK MOD and NATO-aligned programmes.

How does SAPIENT work?

All edge nodes integrating into a system do so via TCP connections to a single fusion node, with messages encoded using Protobuf.

When an edge node first connects, it sends a registration message over this connection, which is processed and acknowledged by the fusion node.

This message specifies the type of device the edge node represents, the information it will report to the fusion node, and the commands the fusion node can use to control it. The registration message, as well as all subsequent messages from the edge node, will also contain the UUID for that edge node. This can then be used by the fusion node to uniquely identify the edge node. This is important as different edge nodes in a given system are expected to have quite different capabilities, and this must be managed by the fusion node (ideally in a way that is hidden from the end user).

What are SAPIENT Edge Nodes?

An edge node is any device interacting with the system that can act as a sensor and/or an effector, which includes the following:

• Radars
• Lidars
• RF detectors
• Acoustic sensors
• Jammers
• Cameras
• Laser rangefinders

    
After registering as described above, all edge nodes will periodically send status messages to the fusion node.

This status message reports the current state and position of the edge node and, for devices such as cameras or jammers with pan/tilt capability, includes an update on the direction the edge node is facing.

Any edge node capable of making detections, such as rangefinders or radars (or cameras that are capable of video tracking), will then send detection messages, which will include the position of the object detected, but can also include extra information, such as target classification (provided the edge node is capable of classifying).

All edge nodes can receive and perform at least basic tasks sent by the fusion node, but depending on the edge node's capabilities, it may be able to perform a wider variety of tasks, such as pointing at an area/target for a camera or effector.

How to Use Any Radar as a SAPIENT Edge Node

Cambridge Pixel's SPx Track Manager and SPx Server software can be used to turn radars that are not currently SAPIENT-compliant into SAPIENT edge nodes, outputting target data (for SPx Track Manager) or radar video (for SPx Server).

This allows existing radars to be made SAPIENT-compliant quickly and easily.

What are SAPIENT Fusion Nodes?

A fusion node is the endpoint in the system, responsible for receiving and processing all the information from the nodes connected to it and issuing tasks to the edge nodes. The fusion node will normally either directly feed or be integrated into a Command and Control (C2) or other application that handles the display of information. The exact amount of information processing and decision-making performed by a given fusion node and a given display application will vary across systems.

Fusion nodes are hierarchical, with a fusion node able to connect to and serve as a child of a higher-level fusion node.

In this way, a system could comprise a number of fusion nodes, each amalgamating and processing information from various sensors for a different local site, and then all connecting to a top-level fusion node, which will amalgamate and process information for the whole system.