Servo

Hi guys!

I am new to Arduino and am currently working on a project which will open a door using a servo motor. The one I have is too small and I think it will not get the job done (micro servo). I was wondering if anyone here knows what type of servo I should use, and anyone other advice (will arduino be able to fully power the servo?).

I will be using the servo to power a mechanism that pulls down the door handle.

Thank in advance for the help :slight_smile:

A bigger servo?

You need to measure the torque needed to turn the handle and then get a servo that has greater torque.

Torque is measured in Newton metres (or lbs feet). For example a force of 9.8 Newtons (1 Kg) acting at the end of a 1 metre lever is a torque of 1 Nm. It would be the same as 2Kg acting at a distance of 0.5 metres. Hanging a weight on the door handle and measuring the distance from the centre of rotation will give you an idea of the torque. Assume a substantial margin of error.

…R

You may want to consider using a different motor. There are many high torque, inexpensive, small dc gear motors available to use in lieu of a pricey high torque servo. - Scotty

Hobbyking has a large selection of different size servos available when the amount of force to operate the latch is determined.

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=22930

http://www.hobbyking.com/hobbyking/store/__18743__Vigor_VSD_11YMB_MG_HV_Extra_Large_360_Degree_Winch_Servo_0_75sec_40kg_150g.html

You might look for car electric locking servos, they should only be about 10 each