New Framework Enables Verification of Modular Robotic Systems Using Formal Logic

Ensuring that robotic systems operate safely and reliably in critical applications has become increasingly challenging as these systems grow more complex and autonomous. A new approach addresses this challenge by leveraging the modular structure of modern robot software to make verification more tractable.

The Challenge of Verifying Complex Robots#

When robots operate in safety-critical environments—such as nuclear inspection or hazardous exploration—their software must perform reliably under all conditions. As these systems incorporate more autonomous components and use distributed architectures like Robot Operating System (ROS), traditional verification methods struggle to scale. The modularity of these systems, while useful for engineering, has not been systematically exploited for verification purposes.

A Compositional Verification Method#

Researchers have developed a compositional approach that treats each software component of a robot as a verifiable unit with formal guarantees. Rather than attempting to verify an entire system at once, the method breaks it into individual nodes—distinct software modules that can be specified and checked independently. Each node receives a formal specification using First-Order Logic (FOL) assume-guarantee contracts, which describe what the module should do and what assumptions it makes about its environment.

The key innovation is introducing inference rules that allow node-level contracts to be composed upward, enabling system-level properties to be derived from verified components.

RCL and Automated Verification#

To make this approach practical, the researchers introduced the ROS Contract Language (RCL), a domain-specific language designed to capture a node's formal specification and connect it directly to the actual ROS implementation code. A tool called Vanda automatically translates RCL contracts into executable runtime monitors—software that watches the system execute and confirms it meets its specifications.

Real-World Application#

The framework was tested on an autonomous rover designed to inspect nuclear sites remotely. This scenario demonstrates the approach's value in a genuinely safety-critical domain where formal assurance is essential. Additional examples showcase other capabilities of the framework.