Vision is essential to bees, as it is the primary sense used to avoid obstacles in the environment, find flowers to collect nectar from, and find the way back to the hive.
Our interest lay in how the bee uses vision to perform all of these tasks, and we started first with the simplest task: how bees avoid obstacles.
The early Green Brain models of the visual system were those systems primarily used for basic flight control. We modelled the circuits which are responsible for motion detection and in turn, are used for flight control tasks (like regulating velocity and roll/pitch/yaw manoeuvres).
Bees primarily use vision to navigate through their environment. This ability to navigate starts with the relatively simple flight control task of avoiding obstacles in the environment. Experiments investigating this task have found two basic control mechanisms that bees use: the optomotor response and the corridor centring response.
The optomotor response allows bees to fly in straight lines by acting to oppose rotations of the visual field. Deliberate turns by the bee occur faster than the optomotor response can detect and are not affected.
This video shows a model of the optomotor response as it acts to oppose the rotation of a drum around the simulated bee:
The corridor centring response allows bees to maintain distance from obstacles and the ground and also to regulate their speed. It utilises angular velocity, a measure of the speed that objects move across the visual field.
The farther away an object is the less angular velocity will be detected. Therefore, angular velocity gives a measure of the distance to the obstacles the bee is moving past, and allows the bee to change its position to avoid getting too close to obstacles.
See our Resources page for instructions for obtaining and running the Corridor Centring Model.