A transporter for transporting a subject over a surface that may be
irregular. The transporter includes a support platform for supporting a
load, the loaded support platform defining fore-aft and lateral planes
and characterized by a load distribution. A plurality of ground
contacting elements are coupled to the support platform. At least one of
the plurality of ground contacting elements is driven by a motorized
drive arrangement. A sensor module generates a signal indicative of the
load distribution of the loaded support platform. Based at least on the
load distribution, a controller commands the motorized drive arrangement.