Moving the Finch robot

There are 6 methods for robot motion in Snap!

move Finch forward and move Finch backward:
sets both wheels to the same power, range is 0 to 100% power (sending values of -1 to -100 will move wheels in the other direction).

turn Finch clockwise/right and turn Finch counterclockwise/left:
turns Finch in place, range is 0 to 100% power.

set Finch wheels:
Lets you set each wheel individually, range is -100 to 100.

stop Finch:
stops the Finch

Problem: The Finch doesn't move straight or turn accurately

The Finch's movements are not repeatable - a timed turn that moved 90 degrees might move 110 degrees the next time.

Cause: The Finch's tether makes repeatable movements difficult - turns cause the tether to twist, causing a spring force that tends to resist continued turning in the same direction. The tether may also drag on the Finch causing it to turn slightly when it should move straight. You can minimize the effect of the tether by:

Holding the tether overhead while the Finch is moving.
Adding weight to the Finch (pennies taped to the underside work well).
Avoiding activities and assignments that call for accurate movement - the Finch will not do well in maze navigation, but will follow a light source just fine.

Ultimately, inaccurate movement is the main drawback of the tether. The Finch could be wireless, but the cost of a wireless tether + batteries would nearly double the Finch's retail price.