Modeling user expertise for choosing levels of shared autonomy

Abstract

In shared autonomy, a robot and human user both have some level of control in order to achieve a shared goal. Choosing the balance of control given to the user and the robot can be a challenging problem since different users have different preferences and vary in skill levels when operating a robot. We propose using a novel formulation of Partially Observable Markov Decision Process (POMDP) to represent a model of the user's expertise in controlling the robot. The POMDP uses observations from the user's actions and from the environment to update the belief of the user's skill and chooses a level of control between the robot and the user. The level of control given between the user and the robot is encapsulated in macro-action controllers. A user study was run to test the performance of our formulation. Users drive a simulated robot through an obstacle-filled map while the POMDP model chooses appropriate macro-action controllers based on the belief state of the user's skill level. The results of the user study show that our model can encapsulate user skill. The results also show that using the controller with greater robot autonomy helped users of low skill avoid obstacles more than it helped users of high skill.