The Virtual Environment Vehicle Interface: a dynamic, distributed and flexible virtual environment

The Virtual Environment Vehicle Interface (VEVI) is a software environment developed for the control and visualization of remotely located robotic vehicles. The design and implementation of this interface were driven by experience with several field missions which have defined key areas to be addressed. This paper describes three of these concepts and demonstrates the approach with examples from recent missions. Dynamic environment VEVI is a dynamic environment and the validity of the interface is in part defined by its ability to represent generic dynamic data. Applications often require data generated at rates that can vary by several order of magnitude. In addition, it is necessary to differentiate reliable delivery of data packets, where each and every bit of information counts (paths, sequences of actions, etc.) and best-effort delivery, where we are only interested in the latest update received (vehicle telemetry, fast streams of data). Finally, the inherent nature of the environment usually represented implies a changing number of entities existent in the environment, therefore dynamic creation and destruction of entities has to be supported. Distributed environment The principal focus of a planetary mission is the ability to obtain good science data, and it is necessary to allow multiple users to share real-time mission data. Control of the different science payloads can be delegated to one particular participant, where others can only observe results and implications of this particular element. Participants can be distributed across the world and include passive observers, like schools or individuals. Flexible environment Since mission targets and vehicle configuration define each instance of the environment, it was necessary to create a flexible framework which would allow easy modification of the environment characteristics as well as integration of new capabilities. The concept of distributed nodes that can be connected to the environment also allows for interchangeability and flexible implementation for each situation.