STUART - Stable Transport in Uneven And Rough Terrains

STUART with a view of the open chassis
© Fraunhofer IML/G. Katsimitsoulias
STUART with transfer station
© Fraunhofer IML/J. Hamm
STUART with obstacle
© Fraunhofer IML/J. Hamm

The STUART chassis is an innovative, patented chassis concept. It solves the static over-determination of conventional four-wheeled chassis without costly and maintenance-intensive springs, dampers, or actuators. Thanks to its simple design, the chassis can be scaled in size and load capacity and is suitable for almost any application.

The STUART chassis has one front and one rear support wheel, as well as two drive wheels placed centrally, forming a central differential drive axis. All wheels are connected to each other with simple levers and joints, forming two coupled support triangles. This allows all four wheels to maintain contact with the ground at all times.

This chassis design ensures the stability of four-wheeled chassis and prevents the typical "tilting" of unsprung four-wheel vehicles on uneven ground. The lever ratios are designed in such a way that the majority of the transported load acts on the drive axis, ensuring sufficient contact pressure for the drive at all times. The central differential drive and low overall height ensure good maneuverability even in tight spaces. This characteristic eliminates the need to restructure the operating environment due to lack of space. The fact that all four wheels have ground contact at all times allows the use of AGV with the STUART chassis even in halls with highly uneven ground, which is actually unsuitable for AGV, as it does not require extensive renovation. Due to the lack of unnecessary suspension on the chassis, the loading surface remains a non-yielding plane that does not change its position during the loading process. Furthermore, it is not necessary to compromise between good suspension for the empty or loaded vehicle.