Glossary

Term	Description
`Header node`	A node which connects to other nodes with the intended function of grouping those nodes. "Header" indicates the grouped nodes are generally the successors of the header node, but this need not always be the case.
`Successors and Predecessors`	Successors and Predecessors are two types of relationships shared between nodes. If node A is a successor of node B, it means there is an edge in the direction from B to A. If node A is a predecessor of Node B, the edge connecting the nodes points from A to B.

Term	Description
`Ego`	The vehicle whose behaviour is of primary interest to us. For scenario videos rendered in dRISK's scenario gym, the ego vehicle is rendered in the colour red.
`Hazard`	The vehicle or object which is involved in the collision or near-miss with the ego vehicle. If multiple vehicles come into contact with the ego, the first vehicle to collide with the ego is taken as the hazard.
`Point of Interest`	The position at which the ego and hazard are closest during the scenario. This will either be at the crash point, if a collision occurs, or at the position where a near-miss occurs.
`VRU`	VRU stands for Vulnerable Road User, examples of which are pedestrians and cyclists.
`ODD`	ODD stands for Operational Design Domain and outlines the exact operating conditions for an automated system such as environmental, geographical and time of day constraints.

Missing Definition? Pop an email over to shona@drisk.ai with the term and we will add a description to this page for future reference.

Last update: 2023-10-25