Collaborative localization is an essential capability for a team of robots such as connected vehicles to collaboratively estimate object locations from multiple perspectives with reliant cooperation. To enable collaborative localization, four key challenges must be addressed, including modeling complex relationships between observed objects, fusing observations from an arbitrary number of collaborating robots, quantifying localization uncertainty, and addressing latency of robot communications. In this paper, we introduce a novel approach that integrates uncertainty-aware spatiotemporal graph learning and model-based state estimation for a team of robots to collaboratively localize objects. Specifically, we introduce a new uncertainty-aware graph learning model that learns spatiotemporal graphs to represent historical motions of the objects observed by each robot over time and provides uncertainties in object localization. Moreover, we propose a novel method for integrated learning and model-based state estimation, which fuses asynchronous observations obtained from an arbitrary number of robots for collaborative localization. We evaluate our approach in two collaborative object localization scenarios in simulations and on real robots. Experimental results show that our approach outperforms previous methods and achieves state-of-the-art performance on asynchronous collaborative localization.
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Bayesian Deep Graph Matching for Correspondence Identification in Collaborative Perception
Correspondence identification is essential for multi-robot collaborative perception, which aims to identify the same objects in order to ensure consistent references of the objects by a group of robots/agents in their own fields of view. Although recent deep learning methods have shown encouraging performance on correspondence identification, they suffer from two shortcomings, including the inability to address non-covisibility in collaborative perception that is caused by occlusion and limited fields of view of the agents, and the inability to quantify and reduce uncertainty to improve correspondence identification. To address both issues, we propose a novel uncertainty-aware deep graph matching method for correspondence identification in collaborative perception. Our method formulates correspondence identification as a deep graph matching problem, which identifies correspondences based upon graph representations that are constructed from robot observations. We propose new deep graph matching networks in the Bayesian framework to explicitly quantify uncertainty in identified correspondences. In addition, we design novel loss functions in order to explicitly reduce correspondence uncertainty and perceptual non-covisibility during learning. We evaluate our method in the robotics applications of collaborative assembly and multi-robot coordination using high-fidelity simulations and physical robots. Experiments have validated that, by addressing uncertainty and non-covisibility, our proposed approach achieves the state-of-the-art performance of correspondence identification.
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- Award ID(s):
- 1942056
- PAR ID:
- 10318779
- Date Published:
- Journal Name:
- Robotics Science and Systems (RSS)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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