I (and, I am sure, Dean Kamen!) would like to know what the rider was attempting to do. I strongly suspect he got one wheel up on the curb or misjudged the curb cut. The dynamic stabilization system works only in the fore-aft direction. Kamen has never claimed that riding a Segway makes one invincible or untippable.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069