He is suggesting that better methods of interviewing could increase “area under the curve”, improving both fase negative and false positive rates at once.
Most robots are passively balanced by having multiple wheels on the ground. Walking robots balance actively without active gyros by moving their limbs.
Spacecraft (which most roboticists would call robots) typically orient themselves using a combination of reaction wheels, magnetic torquers and thrusters. The reaction wheels spin rotate the aircraft by “taking” angular momentum into their own rotation. They don’t require a local magnetic field or the expenditure of fuel, so are a nice choice.