Emergent Control of Ant Learning Walks in a Mobile Robot
Before foraging, desert ants perform learning walks (LWs) to acquire visual memories around their nest. With experience, these walks expand, become straighter, and contain fewer visual scans. We previously proposed a model in which these behaviours emerge from the angular mismatch between path integration (PI) and a mushroom-body-inspired visual compass (VC). Here, we test whether this mechanism can generate learning walks on a physical robot, despite the sensory and motor noise inherent to real-world conditions. We implement the model on a four-wheeled robot equipped with a panoramic camera, an IMU and wheel encoders providing compass and stride information for PI, and test it outdoors using a replicated desert-ant experimental setup. The PI--VC mismatch regulates walking speed, turning, pirouettes, and returns to the nest, while PI provides a teaching signal for visual learning. The robot autonomously decides when to acquire visual memories, while its behaviour gradually shifts from exploration towards foraging as visual learning progresses. The robot reproduces desert-ant LW features, including expanding and straightening trajectories, decreasing pirouette frequency, and improved visual homing. These results demonstrate that a simple error-driven mechanism can generate key features of learning walks under real-world conditions, supporting its plausibility as an explanation for active visual learning in desert ants. More broadly, this work illustrates how physical robots can be used to test biological models.