Efficient Inference of Temporal Task Specifications from Human Demonstrations using Experiment Design.

Robotic deployments in human environments have motivated the need for autonomous systems to be able to interact with humans and solve tasks effectively. Human demonstrations of tasks can be used to infer underlying task specifications, commonly modeled with temporal logic. State-of-the-art methods have developed Bayesian inference tools to estimate a temporal logic formula from a sequence of demonstrations. The current work proposes the use of experiment design to choose environments for humans to perform these demonstrations. This reduces the number of demonstrations needed to estimate the unknown ground truth formula with low error. A novel computationally efficient strategy is proposed to generate informative environments by using an optimal planner as the model for the demonstrator. Instead of evaluating all possible environments, the search space reduces to the placement of informative orderings of likely eventual goals along an optimal planner's solution. A human study with 600 demonstrations from 20 participants for 4 tasks on a 2D interface validates the proposed hypothesis and empirical performance benefit in terms of convergence and error over baselines. The human study dataset is also publicly shared.