View unanswered posts | View active topics It is currently Mon Sep 01, 2014 10:04 pm






Reply to topic  [ 2 posts ] 
servo control using potentiometer 
Author Message
Rookie

Joined: Wed Jun 02, 2010 1:19 am
Posts: 1
Post servo control using potentiometer
hello guys
i am going to do my final year project regarding the servo control
because i am going to construct a robotic arm
basically,i need some guides to do it
i need some guidance how the potentiometer can control the servo rotation respectively by rotating the potentiometer probe
i've been watching some videos on youtube where got some people already succesfully do it
so I really appreciate if someone can help me in this
roughly,i am going to do it using 8051 as the brain and for sure i need adc to convert the continuous signal from the potentiometer to digital signal
thats the only basic thing i know
really need some guidance from some experts here:cry:
thank you very much~


Wed Jun 02, 2010 1:22 am
Profile
Moderator
Moderator
User avatar

Joined: Wed Mar 05, 2008 8:14 am
Posts: 3209
Location: Rotterdam, The Netherlands
Post Re: servo control using potentiometer
mongkiosk,

This isn't really NXT or ROBOTC related is it?

I've never used an 8051, but I'll give you at least some theory of operation.
Say you have an ADC (Analogue to Digital Converter) that is 10 bits, that means that you have 1024 steps that you can measure. Say you can rotate your arm 180 degrees and by doing so, the pot meter moves all the way from one end to the other. That means that for every degree the robot arm moves, the ADC will detect a change of 1024/180, which is roughly equal to 5. So if your ADC is giving you a reading of 760, that means the arm is at around (760/1024) * 180 = 134 degrees.

ADCs come in many shapes and sizes. I am a big fan of the MAX127 because it has an I2C interface. I am not sure if I2C is the way you want to go, a simpler SPI version may be more useful to you. You're going to have to do some research yourself for that. It may also be a good thing to try and find a forum with 8051 programmers, they will be more able to help you with this.

Regards,
Xander

_________________
| Professional Conduit of Reasonableness
| (Title bestowed upon on the 8th day of November, 2013)
| My Blog: I'd Rather Be Building Robots
| ROBOTC 3rd Party Driver Suite: [Project Page]


Wed Jun 02, 2010 3:59 am
Profile WWW
Display posts from previous:  Sort by  
Reply to topic   [ 2 posts ] 

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  



Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by ST Software for PTF.