[Cal578]

Originally Posted by Kusha

This question seems like it would fit this thread, would a tape measure be allowed on the field?

Yes, but...

Originally Posted by dodar

No measuring devices are allowed on the field by team members.

Not strictly true, this year.

Originally Posted by Game Manual

3.2.2.3 G07
TEAMS may not cause significant or repeated delays to the start of a MATCH.

TEAMS are expected to stage their ROBOTS for a MATCH safely and swiftly. TEAM efforts that, either intentionally or unintentionally, delay the start of a MATCH will not be tolerated. Examples of such delays include, but are not limited to:
A. Use of alignment devices such as templates, tape measures, laser pointers, etc. to precisely place and/or align the ROBOT.
B. Late arrival to the FIELD.
C. Being indecisive about where/how to position a ROBOT.
D. Installing BUMPERS, or any ROBOT maintenance or assembly, once on the FIELD.

[Blue text represents the blue box in the rules; emphasis mine]

So, you can use a tape measure if you're quick about it. "Significant delay" is at the discretion of the Head Referee, so you'd better be careful. You might be able to find something faster (and more discrete) than a tape measure. For example, get a piece of string and tie knots in it at your desired distance from some reference point. That way, you'll be able to position your robot quickly and consistently, without getting penalized for delay.