v. To randomly adjust the settings of an object, such as the dials on a piece of equipment or the options in a software program, particularly in an effort to learn how the object works.
1994
Why is babbling so important? The infant is like a person who has been given a complicated piece of audio equipment bristling with unlabeled knobs and switches but missing the instruction manual. In such situations people resort to what hackers call frobbing — fiddling aimlessly with the controls to see what happens.
1990
The molecular model of an actual anti-cancer drug molecule(methotrexate) was already positioned inside the model of the protein receptor site (dihydrofolate reductase). My job was to find an exact fit in which the two compounds could tightly bind. The arm has six degrees of freedom, and exerts enough force to tire your arm if you actively wrestle with a molecule for many minutes. I tried to twist, rotate, jam, tweak, and frob the thing into place by looking at the 3D jigsaw puzzle on the screen and manipulating it with my hand.
1981 (earliest)
FROBNICATE v. To manipulate or adjust, to tweak. Derived from FROBNITZ (q.v.). Usually abbreviated to FROB. Thus one has the saying "to frob a frob". See TWEAK and TWIDDLE. Usage: FROB, TWIDDLE, and TWEAK sometimes connote points along a continuum. FROB connotes aimless manipulation; TWIDDLE connotes gross manipulation, often a coarse search for a proper setting; TWEAK connotes fine-tuning. If someone is turning a knob on an oscilloscope, then if he's carefully adjusting it he is probably tweaking it; if he is just turning it but looking at the screen he is probably twiddling it; but if he's just doing it because turning a knob is fun, he's frobbing it.