Graph Convolutional Network based Configuration Detection for Freeform Modular Robot Using Magnetic Sensor Array

Modular self-reconfigurable robotic (MSRR) systems are potentially more robust and more adaptive than conventional systems. Following our previous work where we proposed a freeform MSRR module called FreeBOT, this paper presents a novel configuration detection system for FreeBOT using a magnetic sensor array. A FreeBOT module can be connected by up to 11 modules, and the proposed configuration detection system can locate a variable number of connection points accurately in real-time. By equipping FreeBOT with 24 magnetic sensors, the magnetic field density produced by magnets and steel spherical shells can be monitored. The connectable area is split into 199 non-uniform regions, including 84 uniform regions. Using a Graph Convolutional Network (GCN) based algorithm, the connection points can be located accurately under ferromagnetic environments. The system can locate a variable number of connection points for such a region division with only single connection point training data. Finally, the localization algorithm can run faster than 40 Hz on FreeBOT. With the real-time configuration detection system, the FreeBOT system has the potential to reconfigure automatically and accurately.

Authors

• Yuxiao Tu
• Guanqi Liang
• Tin Lun Lam

Keywords

• Location awareness
• Magnetic sensors
• Conferences
• Training data
• Robot sensing systems
• Real-time systems
• Steel
• Magnetometer
• Sensor Array
• Graph Convolutional Network
• Magnetic Array
• Modular Robots
• Magnetic Sensor Array
• Magnetic Field
• Magnetic Flux
• Local Algorithm
• Connection Point
• Single Training
• Regional Division
• Neural Network
• Training Set
• Artificial Neural Network
• Validation Set
• Good Accuracy
• Undirected
• Multilayer Perceptron
• Hysteresis Loop
• External Magnet
• Unscented Kalman Filter
• Inertial Measurement Unit
• Relative Permeability
• Magnetic Field Strength
• Magnetic Dipole
• Low Carbon Steel
• Validation Accuracy
• Levenberg-Marquardt Algorithm
• Magnetic Moment