Da Vinci's engineering drawings were invaluable when the industrial revolution began, and many things he conceptualised for the first time are still in use today in forms very similar to his original ideas. Yes, that includes the hang glider and the bicycle.
He drew designs demonstrating the principles of flywheels, spindles, ball bearings, rolling bearings, pulleys, pile drivers, floodlights, crank elevators, odometers, cog wheels, gears and gear shifts, cranes, ratchets, jacks...
He also designed machines for making springs and screws, cutting stone, twisting ropes, milling grain, pressing oil, printing, excavating, and making mirrors and lenses.
The man possibly contributed more to the modern world we live in than anyone else, except possibly Nikola Tesla.