@Snark wanted to explore the creative boundaries of robotically enhanced transportation, so h e built the H.B.K.T., or Happy Ballistic Kerbal Transporter. This electric catapult is a simple contraption with two large Square Hinges, plus one Small Square Hinge.  The two big hinges are motorized, the little one is not (it's a free pivot).  After slapping it toget her in the VAB, he just used some slider controls on the hing es' Part Action Window to set up their properties.  To activate the f