William Nelson – killed by prototype of a motorized bicycle

Otto Lilienthal – crashed one of his hang gliders

Marie Curie – died of radiation sickness after  isolating radium

Perillos of Athens – killed by the Brazen Bull (a torture device) he invented (he was the first test subject)

Thomas Midgley, jr – killed by the rope and pulley system he invented to help get him out of bed

Thomas Andrews – an architect of the Titanic who was on the ship during its maiden voyage

H.L. Hunley – invented the submarine and died on one during the testing phase when it wouldn’t resurface