# How to get the accurancy of the position system?

I want to build a system for positioning objects. It should be driven by a DC motor and a sensor should control the rotation angle.

For the positioning I want to design (calculation) the accuracy. How it can be done and what parameter should be consider?

What minimal angle or number of rotations can be done with a DC motor?

I want to rotate the DC motor with a minimal angle of 400°. Can it be done or have DC motors minimal rotation angle to make start and stop motion? I do not know what which characteristics should be accounted for.

The amount of rotation that the motor is capable of depends on the physical design of the motor. Usually the motor is combined with a transmission (eg gears) of some kind which also influence how far the combination (called an Actuator) can move.

Many motors, and many actuators, can rotate infinitely, without limit.

The minimal angle that one can reliably get an actuator to do is also dependent on the physical design. Again, there is not really a limit to how small one can go, but other physics start to become problems.

The calculations depend on the physical structure chosen.

To get better help, edit your question above to tell us:

1. The mass and volume of the objects to be positioned.

2. The desired precision and maximum in positioning (linear or angular)

3. The amount of money you can spend to create the solution.

This should be enough info for people to suggest an approach.