Servo motor - Electronic Circuits Projects Diagrams Free

uaefame · 27th October 2008, 02:25 PM

Hello everyone,

I bought a servo motor from a hobby shop JR DS8911.
I am trying to test it using function generator.

The problem is I can't get it moving?

Any ideas How to turn a servo motor.

It comes with 3 wires 1power 2ground 3control.

The control wire is hooked up into the function generator.

Q> What is the required setting to turn a servo motor using function generator.

Thanks in advance

ericgibbs · 27th October 2008, 02:55 PM

Quote:

Originally Posted by uaefame

Hello everyone,

I bought a servo motor from a hobby shop JR DS8911.
I am trying to test it using function generator.

The problem is I can't get it moving?

Any ideas How to turn a servo motor.

It comes with 3 wires 1power 2ground 3control.

The control wire is hooked up into the function generator.

Q> What is the required setting to turn a servo motor using function generator.

Thanks in advance

hi,
Look here for some data.

Servo Basics

Pommie · 27th October 2008, 03:09 PM

You really should try to use google before asking such basic questions.

Mike.

ericgibbs · 27th October 2008, 03:20 PM

hi Hesham,
I have realised you uses the word 'turn' for the digital servo motor.

A servo will only 'turn' , that is rotate, less than an angle of 300 degress or so, its not a stepper motor.

Build the 555 circuit shown in the link and test/learn from the servo control before you consider using the 16F818 PIC.

uaefame · 27th October 2008, 04:22 PM

Thanks again,

BTW, the 555 timer is it important to be build?

Because I am interested to control the servo angle using microcontroller PIC16f818.

pic 16f818 contain internal timer. So, I think no need of Timer 555?

Just asking?

BTW, the concept of 20ms? and the range 1ms-2ms with 1.5ms to be 90degree.

The on signal for 1ms-2ms (The on signal to control the angle) and off signal for 10-30ms (Just to make sure the signal servo is on).

Is this how it is?

Thanks in advance

ericgibbs · 27th October 2008, 05:03 PM

Quote:

Originally Posted by uaefame

Thanks again,

BTW, the 555 timer is it important to be build?

Because I am interested to control the servo angle using microcontroller PIC16f818.

pic 16f818 contain internal timer. So, I think no need of Timer 555?

Just asking?

BTW, the concept of 20ms? and the range 1ms-2ms with 1.5ms to be 90degree.

The on signal for 1ms-2ms (The on signal to control the angle) and off signal for 10-30ms (Just to make sure the signal servo is on).

Is this how it is?

Thanks in advance

hi,
I have not seen the datasheet for your servo, but the timings of 1 to 2mSec at 20mSec intervals sound about right.

I suggested the 555 so that you could just test and check out the servo.

If you feel confident to write a program for the 16F818 give it a try.

uaefame · 28th October 2008, 01:45 PM

I am interested in know the period?
The on time range?
The off time range?
the duty cycle time range?

If you know how to find these using experiment please provide it!
Thanks in advance

blueroomelectronics · 28th October 2008, 01:52 PM

Issue 1 of the JPUG newsletter has a servo test program for the 18f. A 16f version was posted in the forums ages ago.

uaefame · 28th October 2008, 02:20 PM

hmm, Thanks blueroomelectronics

BTW its ISSUE 2 of the JPUG newsletter.

Thanks again, I will start reading it.

uaefame · 28th October 2008, 05:15 PM

I tried seeting the On time to 1.5ms and the off time to 20ms and repeated it 70 times.

It doesn't go to 90 degree? and it keep going on and on hitting the far right limit and jerking at that point.

Please help

If you have an idea about servo motor. I tried using the tutorial mentioned above but no use. If you know how to find the information about servo motor please let me know. Information concerning On time and Off time.

Thanks in advance

ericgibbs · 28th October 2008, 05:19 PM

hi Hesham,
This is the reason I suggested the 555 servo driver circuit, as you dont have details of the servo, it would enable you to determine experimentally the control required.

blueroomelectronics · 28th October 2008, 06:13 PM

The 555 is good advice but you better skip it and work on the PIC version or you'll never meet your Dec 8 deadline and you're hoping to control 18 servos? At the rate you're progressing you will not make it.

uaefame · 28th October 2008, 06:21 PM

Hmm, I will build this timer. For the time being, if anyone know the value of frequency for a digital servo let me know. I am working with 70Hz and it was bad!

Any ideas

Thanks in advance

blueroomelectronics · 28th October 2008, 06:26 PM

It's a pulse between 1ms to 2ms that arrives at 20ms intervals.

uaefame · 28th October 2008, 08:08 PM

I think its even lower because I am using digital servo.

I could control it using function generator, somehow using 280Hz and duty cycle of 22%-61% (angle 0 till 120degree). I am interested in going up to 180degree. why the servo won't rotate that much. When I try doing it by hand it move the remaining 60degree?

Strange

Anyone knows how can i rotate a servo till 180degree its 120degree right now??

Thanks in advance

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27th October 2008, 02:25 PM	#1
uaefame	Servo motor Hello everyone, I bought a servo motor from a hobby shop JR DS8911. I am trying to test it using function generator. The problem is I can't get it moving? Any ideas How to turn a servo motor. It comes with 3 wires 1power 2ground 3control. The control wire is hooked up into the function generator. Q> What is the required setting to turn a servo motor using function generator. Thanks in advance __________________ Hesham Ismail Mohammed Sharif Thank me if you want

27th October 2008, 03:09 PM	#3
Pommie	You really should try to use google before asking such basic questions. Mike.

27th October 2008, 03:20 PM	#4
ericgibbs	hi Hesham, I have realised you uses the word 'turn' for the digital servo motor. A servo will only 'turn' , that is rotate, less than an angle of 300 degress or so, its not a stepper motor. Build the 555 circuit shown in the link and test/learn from the servo control before you consider using the 16F818 PIC. __________________ Eric " Good enough is Perfect " I will NOT answer PM's requesting technical help, please use the Forum PIC tutorials: Nigel's www.winpicprog.co.uk/ Bill's: www.blueroomelectronics.com/

27th October 2008, 04:22 PM	#5
uaefame	Thanks again, BTW, the 555 timer is it important to be build? Because I am interested to control the servo angle using microcontroller PIC16f818. pic 16f818 contain internal timer. So, I think no need of Timer 555? Just asking? BTW, the concept of 20ms? and the range 1ms-2ms with 1.5ms to be 90degree. The on signal for 1ms-2ms (The on signal to control the angle) and off signal for 10-30ms (Just to make sure the signal servo is on). Is this how it is? Thanks in advance __________________ Hesham Ismail Mohammed Sharif Thank me if you want

28th October 2008, 01:45 PM	#7
uaefame	I am interested in know the period? The on time range? The off time range? the duty cycle time range? If you know how to find these using experiment please provide it! Thanks in advance __________________ Hesham Ismail Mohammed Sharif Thank me if you want

28th October 2008, 01:52 PM	#8
blueroomelectronics	Issue 1 of the JPUG newsletter has a servo test program for the 18f. A 16f version was posted in the forums ages ago. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com/

28th October 2008, 02:20 PM	#9
uaefame	hmm, Thanks blueroomelectronics BTW its ISSUE 2 of the JPUG newsletter. Thanks again, I will start reading it. __________________ Hesham Ismail Mohammed Sharif Thank me if you want

28th October 2008, 05:15 PM	#10
uaefame	I tried seeting the On time to 1.5ms and the off time to 20ms and repeated it 70 times. It doesn't go to 90 degree? and it keep going on and on hitting the far right limit and jerking at that point. Please help If you have an idea about servo motor. I tried using the tutorial mentioned above but no use. If you know how to find the information about servo motor please let me know. Information concerning On time and Off time. Thanks in advance __________________ Hesham Ismail Mohammed Sharif Thank me if you want

28th October 2008, 05:19 PM	#11
ericgibbs	hi Hesham, This is the reason I suggested the 555 servo driver circuit, as you dont have details of the servo, it would enable you to determine experimentally the control required. __________________ Eric " Good enough is Perfect " I will NOT answer PM's requesting technical help, please use the Forum PIC tutorials: Nigel's www.winpicprog.co.uk/ Bill's: www.blueroomelectronics.com/

28th October 2008, 06:13 PM	#12
blueroomelectronics	The 555 is good advice but you better skip it and work on the PIC version or you'll never meet your Dec 8 deadline and you're hoping to control 18 servos? At the rate you're progressing you will not make it. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com/

28th October 2008, 06:21 PM	#13
uaefame	Hmm, I will build this timer. For the time being, if anyone know the value of frequency for a digital servo let me know. I am working with 70Hz and it was bad! Any ideas Thanks in advance __________________ Hesham Ismail Mohammed Sharif Thank me if you want

28th October 2008, 06:26 PM	#14
blueroomelectronics	It's a pulse between 1ms to 2ms that arrives at 20ms intervals. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com/

28th October 2008, 08:08 PM	#15
uaefame	I think its even lower because I am using digital servo. I could control it using function generator, somehow using 280Hz and duty cycle of 22%-61% (angle 0 till 120degree). I am interested in going up to 180degree. why the servo won't rotate that much. When I try doing it by hand it move the remaining 60degree? Strange Anyone knows how can i rotate a servo till 180degree its 120degree right now?? Thanks in advance __________________ Hesham Ismail Mohammed Sharif Thank me if you want Last edited by uaefame; 28th October 2008 at 08:08 PM.