page_title: Hunting oscillation
section_title: Road–rail vehicles
hierarchical_section_title: Hunting oscillation / Railway wheelsets / Road–rail vehicles
caption_attribution_description: English: Road-rail vehicle conversion of a Toyota Land Cruiser to allow the vehicle to operate on standard-gauge railway lines.
context_page_description: Hunting oscillation is a self-oscillation, usually unwanted, about an equilibrium. The expression came into use in the 19th century and describes how a system "hunts" for equilibrium. The expression is used to describe phenomena in such diverse fields as electronics, aviation, biology, and railway engineering.
context_section_description: Many road–rail vehicles feature independent axles and suspension systems on each rail wheel. When this is combined with the presence of road wheels on the rail it becomes difficult to use the formulae above. Historically, road–rail vehicle have their front wheels set slightly toe-in which has been found to minimise hunting whilst the vehicle is being driven on-rail.
caption: Independent rail wheel axles are common on road–rail vehicles
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