Comparing the Blackboard Architecture and Intelligent Water Drops for Spacecraft Cluster Control

The contemplation of the use of smaller spacecraft for planetary science missions dictates the consideration of approaches to maximize the value of a more limited (due to lower transmission power and smaller antenna size) communications capability. The focus herein is on autonomous control (as opposed to human teleoperation) which serves to increase science returns via the reduction of command data traffic (and the transmission of the imagery needed to make command decisions) and decreased time spent in a waiting state for controller instructions. This paper presents and contrasts two methods for the control of a cluster of spacecraft: one based on a Blackboard architecture and one based on the Intelligent Water Drop method. It presents data characterizing the two approaches, which shows that the Blackboard approach outperforms the IWD approach in terms of phenomena detection. However, the IWD approach minimizes communications and outperforms with Blackboard approach in terms of the level of exploration conducted.