How would you measure repeatability of an arm that needs to swing exactly 180 degrees (with a sensor mounted on the end?)

Mechanical Engineering Reliability & Mechanical Test
1

How would you measure repeatability of an arm that needs to swing exactly 180 degrees (with a sensor mounted on the end?)

2

The most repeatable senser is a either an encoder or a resolver. (Both have high tolerance and are positional sensors, so it is easy to figure out the exact postion)