orientABC

orientABC is a cross-platform specification and software library for three-dimensional orientation data in mobile, embedded, and robotics applications. It defines a standard data model for attitude, including orientation as a quaternion, angular velocity, and linear acceleration, and prescribes coordinate frames such as body and world. The aim is to provide a consistent interface for obtaining, transforming, and exporting orientation information across devices and software layers.

The library emphasizes modular sensor fusion and offers reference implementations of common filters, including complementary and Kalman variants. It supports quaternions, Euler angles, rotation matrices, and frame transformations, with utilities for converting between representations. It provides sensor interfaces for accelerometers, gyroscopes, and magnetometers, along with calibration for biases and misalignment.

orientABC originated in an international collaboration and is maintained as an open-source project under a permissive license. Implementations exist in C++, Python, and JavaScript, with bindings for mobile and embedded platforms. The project provides documentation, tests, and tutorials to facilitate integration in AR/VR, robotics, and navigation applications.

The project seeks interoperability with existing inertial measurement conventions and middleware, aiming for consistent orientation data across software stacks. It is used in academic research, industry projects, and education to standardize attitude representation and transformation workflows.