Mechanically Heterogeneous Robot Teams Ananth Ranganathan CS-8803L 11/4/2002

Mechanically Heterogeneous Robot Teams Marsupial Robots by Robin Murphy – Chapter 9 Heterogeneous Teams of Modular Robots by Grabowski, Navarro-Serment, Paredis and Khosla – Chapter 10

Marsupial Robots Mother

Outline Characteristics of Marsupial Teams Advantages Heterogeneity in Marsupial teams Roles and Behaviors

Characteristics of Marsupial Teams Mother – Transports and supports one or more daughters – Acts as a mobile base after deployment – Can plan for the daughters globally – Can recharge daughters’ power – Can act as a communications base

Characteristics of Marsupial Teams Daughters – Small and maneuverable but with limited range – Mainly limited to reflexive action – Capable of negotiating rugged terrain – Limited communication capabilities

Advantages of Marsupialism Rapid, energy-efficient transport of distributed resources Increased accessibility Mobile base in the area of operation – Mother acts as communications relay – Mother can recharge daughters – Mother can gather sensor data and plan globally Test bed for research on heterogeneity

Heterogeneity in Marsupial Teams Cognitive Heterogeneity – Differences in cognitive powers – Incidental Mother is a member of the team but provides no processing contribution – Perceptive Mother uses her cognitive abilities to supplement data from daughters – Proxy Mother provides off-board processing capabilities to daughters – Hierarchical Mother issues commands

Heterogeneity in Marsupial Teams Behavioral Heterogeneity – Differences in relationship between mother and daughters – Courier – Messenger – Manager – Coach Physical Heterogeneity

Roles and Behaviors Courier: Deploy and Docking – When to deploy If the mother cannot make any further (direct) progress, but the daughters can and the goal is within communication range If ratio of mother’s travel time to goal and daughters’ power consumption is high and goal is within communication range

Roles and Behaviors Manager, Coach and Messenger: MaintainLOS – Mother has to remain in daughters’ perceptual range – Daughter can go into regions where mother cannot follow – What steps to take if communication is lost

Docking Mother-centric Daughter-centric Local or Centralized sensing Distributed docking – Multiple daughters docking Active Cooperative docking – Central control – Set of societal rules