Mobile robot navigation via olfaction has been receiving considerable interest over recent years to assist in the development of advanced cognitive robots which are able to operate in natural environments. With the related advances in electronic noses, it is now possible to detect and recognize and locate a range of different odours for a variety of applications. This paper involves designing and building a chemical sensing mobile robot that is able to navigate using these latest olfactory sensors. A smart robot equipped with olfactory sensors is designed for performing various search tasks in chemical fields; these search tasks include locating point sources, following chemical trails and plume following and investigating how the search efficiencies can be enhanced.