The Multi-Chamber Electronic Nose—An Improved Olfaction Sensor for Mobile Robotics

TLDR

Metal oxide semiconductor sensors suffer long recovery times, limiting their use in mobile robotics where rapid gas concentration changes occur. This paper presents a new e‑nose design that largely eliminates this limitation. The Multi‑Chamber Electronic Nose uses four identical MOS sensor sets housed in separate chambers that alternate between sensing and recovery, enabling faster overall chemical concentration detection. Experiments demonstrate that the MCE‑nose enables rapid gas concentration sensing and effective mobile robot gas mapping.

Abstract

One of the major disadvantages of the use of Metal Oxide Semiconductor (MOS) technology as a transducer for electronic gas sensing devices (e-noses) is the long recovery period needed after each gas exposure. This severely restricts its usage in applications where the gas concentrations may change rapidly, as in mobile robotic olfaction, where allowing for sensor recovery forces the robot to move at a very low speed, almost incompatible with any practical robot operation. This paper describes the design of a new e-nose which overcomes, to a great extent, such a limitation. The proposed e-nose, called Multi-Chamber Electronic Nose (MCE-nose), comprises several identical sets of MOS sensors accommodated in separate chambers (four in our current prototype), which alternate between sensing and recovery states, providing, as a whole, a device capable of sensing changes in chemical concentrations faster. The utility and performance of the MCE-nose in mobile robotic olfaction is shown through several experiments involving rapid sensing of gas concentration and mobile robot gas mapping.