Publications / 2003 Proceedings of the 20th ISARC, Eindhoven, Holland

Research of the Snaking Phenomenon to Improve Directional Stability of Remote Controlled Articulated Wheel Tool-Carrier

Marian Lopatka, Tomasz Muszynski
Pages 95-101 (2003 Proceedings of the 20th ISARC, Eindhoven, Holland, ISBN 978-90-6814-574-8, ISSN 2413-5844)
Abstract: Articulated wheel tool-carriers manufactured up to 20-25 tons of total weights are wide available on the construction equipment market and have a lot of unique advantages not accessible on Ackerman steering or truck-mounted equipment such as : - for weight up to 20 t high cross-country mobility ? comparable to heavy military tracked vehicles due to size of wheels;
  • excellent manoeuvrability and keeping attachment straight ahead during turning;
  • high lift capacity due to heavy axis construction;
  • high puling force;
  • wide range of tools and attachments due to quick-coupling device;
  • high productivity;
  • high reliability and durability.
Moreover their steering systems and transmission are easy to automation due to hydraulic control systems. For those reasons they could be useful and cost effective on hazardous areas and robotised construction sites. There is one unsolved problem, which limits the speed of operation and efficiency of using ? they have poor directional stability. During straight movement the articulated tractor deviates from straight line and permanent driver correction is required. The path has oscillation shape so it is called snaking phenomenon. So in the case of remote control the speed is limited to 5-6 km/h. The higher road speed above 30 km/h of driver controlled tractor need an operator aid system that would improve directional stability of articulated tractor too. Designing such system demand perfect knowledge of snaking phenomenon arise reasons. This paper describes tests and trials conducted on 20 tons articulated wheel loader to get answer how the snaking phenomenon is arisen. Used methods, achieved original results and their analysis are presented. It could be basis for future works on articulated tractor directional stabilisation system.
Keywords: articulated tractor, high speed, identification, remote control, snaking phenomenon, steering System