Sufficiently perceiving the environment is a critical factor in robot motion generation. Although the introduction of deep visual processing models have contributed in extending this ability, existing methods lack in the ability to actively modify what to perceive; humans perform internally during visual cognitive processes. This paper addresses the issue by proposing a novel robot motion generation model, inspired by a human cognitive structure. The model incorporates a state-driven active top-down visual attention module, which acquires attentions that can actively change targets based on task states. We term such attentions as role-based attentions, since the acquired attention directed to targets that shared a coherent role throughout the motion. The model was trained on a robot tool-use task, in which the role-based attentions perceived the robot grippers and tool as identical end-effectors, during object picking and object dragging motions respectively. This is analogous to a biological phenomenon called tool-body assimilation, in which one regards a handled tool as an extension of one's body. The results suggested an improvement of flexibility in model's visual perception, which sustained stable attention and motion even if it was provided with untrained tools or exposed to experimenter's distractions.
Learning to control a robot commonly requires mapping between robot states and camera images, where conventional deep vision models require large training dataset. Existing visual attention models, such as Deep Spatial Autoencoders, have improved the data-efficiency by training the model to selectively extract only the task relevant image area. However, since the models are unable to select attention targets on demand, the diversity of trainable tasks are limited. This paper proposed a novel Key-Query-Value formulated visual attention model which can be guided to a certain attention target. The model creates an attention heatmap from Key and Query, and selectively extracts the attended data represented in Value. Such structure is capable of incorporating external inputs to create the Query, which will be trained to represent the target objects. The separation of Query creation improved the model's flexibility, enabling to simultaneously obtain and switch between multiple targets in a top-down manner. The proposed model is experimented on a simulator and a real-world environment, showing better performance compared to existing end-to-end robot vision models. The results of real-world experiments indicated the model's high scalability and extendiblity on robot controlling tasks.