Author Topic: FYP_First Robot_The Articulated Robotic Arm control by PLC  (Read 1191 times)

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Offline mrsolid9Topic starter

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FYP_First Robot_The Articulated Robotic Arm control by PLC
« on: December 09, 2012, 11:51:20 AM »
Hi guys, I'm newbie here. I'm doing my final year project of making articulated robotic arm.

The robotic arm used 4 servomotors for overall operation; three for its joints, and one for the gripping mechanism. This robot expected to differentiate glass and other objects based on reflective theory. And how about PLC programming ?

Please someone help me to find some solutions. Any help is appreciated, thanks a lot :)


Offline Tommy

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Re: FYP_First Robot_The Articulated Robotic Arm control by PLC
« Reply #1 on: December 11, 2012, 07:00:20 AM »
most PLC's that I'v played with have a scan time of 10ms, not sure they could work with RC servos
using standard I/O's from a PLC, I believe most have PWM output cards available or you could go
serial with something like http://www.seetron.com/sscasd2.html

Tommy

Offline mrsolid9Topic starter

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Re: FYP_First Robot_The Articulated Robotic Arm control by PLC
« Reply #2 on: December 11, 2012, 10:00:41 PM »
wish you best of luck for your project. and sorry to say that i can't help you in this problem but i am sure that someone in this forum will definitely help you out.
Adam smith
[email protected]
Nitrotek.se

hehe :) i'm very noob about robot dude..looking for someone can guide me..
thanks  :)


most PLC's that I'v played with have a scan time of 10ms, not sure they could work with RC servos
using standard I/O's from a PLC, I believe most have PWM output cards available or you could go
serial with something like http://www.seetron.com/sscasd2.html

Tommy

all types of servomotor happen same problem? now i'm using parallax servomotor..
anyway thanks for response dude.. :)

Offline Tommy

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Re: FYP_First Robot_The Articulated Robotic Arm control by PLC
« Reply #3 on: December 12, 2012, 06:44:04 AM »
Quote
all types of servomotor happen same problem?
Not sure about ALL servomotors, all the PLC controlled servomotors I'v worked on have a servo
drive board that supplies the power for the motor and gets a control voltage(-10 to 10vdc, 0v=stop)
from the PLC(analog output card needed).

It's my understanding that RC servos are PWM controlled, 1.5ms pulse motor turn one direction
2ms motor turn the other direction.


Tommy
« Last Edit: December 12, 2012, 07:36:38 AM by Tommy »

Offline Soeren

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Re: FYP_First Robot_The Articulated Robotic Arm control by PLC
« Reply #4 on: December 12, 2012, 04:50:42 PM »
Hi,

All regular R/C servos (hobby servos) use the same protocol. It's a PDM signal with a repetition rate of ~20ms and a pulse duration from 1ms to 2ms, with 1.5ms being center position.

Unfortunately it's a standard that most servo manufacturers like to break, so the pulse duration may be from ~0.3ms to ~2.8ms worst case, depending on which servo you have.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

 


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