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Author Topic: Question! and Help I need to build a v8 engine servo motor governor  (Read 28912 times)

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Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #90 on: November 07, 2009, 12:42:07 PM »
Hi Neil,

Well did you have a good time on your little adventure to the Embassy/
Hope so it sounds like it would have been a Great time.
I survived... I managed to avoid the garlic loaded snacks (but not the people breathing them) and met some people that I have known for years over the telephone but haven't previously seen live - all in all, it was... Bearable, I guess.


It runs on wood chips from tree trimmers and small chunk wood. And burns cleaner than most autos, very low CO emissions.
Nice... So you're gonna run your car on firewood, so to speak?  :D
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
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Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #91 on: November 08, 2009, 04:38:46 PM »
Hi Neil,

Here's the schematic with the next two sub-circuits attached:
http://That.Homepage.dk/PDF/V8-Speed_Governor_Next_Step.pdf
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #92 on: November 09, 2009, 07:21:12 PM »
Thanks Soren for sending more of the circuit.

I will report back as soon as I get some results. I'll slip that 4093 in tonight.

Thank you Sir ;)

Neil
Take care
Neil

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #93 on: November 09, 2009, 08:34:00 PM »
Hello Mr. Soren

Just a quick question, if the TP3 does not look right should I stop, or continue the circuit? As of now with only the 4093 has been added.

You can see the wave form below.


Sorry for dark picture
Neil
« Last Edit: November 09, 2009, 09:27:33 PM by wheelyneil »
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #94 on: November 10, 2009, 04:38:55 AM »
Hi Neil,

Just a quick question, if the TP3 does not look right should I stop, or continue the circuit? As of now with only the 4093 has been added.
You should allways stop when something is that different, or the error will propagate throughout the rest of the circuit and make it tougher to trouble shoot.

With only the 4093 (plus C2, R5 and VR1 I hope), TP3 should look as stated - a nice clean square.
Please check pins 3 and 4 on the 4093 (and perhaps pin 1). The curve looks somewhat like if your 'scope was AC coupled, but the switch seem to be DC coupled, so perhaps the 4093 is failing, but do these measurements so we can rule on it.

How does TP2 look when TP3 does this?
If you hook up one of the probes to each, and just move the traces apart vertically (eg. upper half for TP2 and lower half for TP3), we can see the signals timing dependencies as well.
As a matter of fact, keeping one of the probes on TP2, will serve as a timing reference for all other measurements you do.

The positive going peaks on TP3 should be concurrent with the negative going spikes on TP2 and the timing of the monoflop seems to be around 9ms, as I suppose the negative going peaks happens when the monoflop times out.

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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #95 on: November 10, 2009, 11:10:03 AM »
Soren
I think we made some progress today.

Here are the Pictures of TP3 and TP4 It seemed that TP3 was close so I added a little more to get the TP4 signal out.

Anyways  here are the pictures and I will wait for my electronics thrashing ;D

Take Care Mr Soren

Neil
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #96 on: November 10, 2009, 04:11:30 PM »
Hi Neil,


Here are the Pictures of TP3 and TP4 It seemed that TP3 was close so I added a little more to get the TP4 signal out.
I don't think TP3 is all that close unfortunately.
The instant TP2 reach 5V (+/- ~1V) on its way down towards 0V, TP3 should go high.
The period TP3 is high should be settable on VR1, to about half the period (at least if the test generator is adjusted to 80Hz/12.5ms - which will make it easier later on). Set it as close to 50% as possible (just by eye).

As long as this is not the case, you should wait with the components right of TP3.


When you go right of TP3, you really need to adjust the test generator period to 12.5ms, as this is the center value we need to integrate (make into a DC voltage).


If you have an extra 4093, try swapping it in, to see if that changes anything.

Btw. I don't know if you are aware of it, but CMOS4000 series are sensitive to Electrostatic Discharge (ESD), so you should touch the ground of your circuit before putting the 4093 in, to discharge any potential difference - fairly high voltages (low current though) are common and can damage the IC.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
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Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #97 on: November 10, 2009, 07:35:43 PM »
Hi Soren

Sorry it was not what you were looking for :(

Quote
The period TP3 is high should be settable on VR1, to about half the period (at least if the test generator is adjusted to 80Hz/12.5ms - which will make it easier later on). Set it as close to 50% as possible (just by eye).

I reset the test gen circuit to as close to 80Hz as possible. Just so you know VR1 gave me no adjustment control, If it did it was so little I could barely detect it and no way could I decrease the high by half. R5=~65k, I checked VR1 it had full range but still no control over the circuit. I swapped out C2 also.

I also switched the 4093 out with 2 others and no change. And as you said I always try to ground myself before touching IC's Just good practice I think ;)

Quote
As long as this is not the case, you should wait with the components right of TP3.

There already gone!

Quote
When you go right of TP3, you really need to adjust the test generator period to 12.5ms, as this is the center value we need to integrate (make into a DC voltage).

I'll Keep a close check on it.

Okay Here is something, when I removed the dual trace signal from the scope and dropped the TP2 it changed the freq of TP3's "HIGH" by about half.
You can see it in the last picture .  It looks like that wave is pretty close to 80Hz. The scope was set at 5v/div and 5mS/div Hope it helps, that you know this info? :-\

Is the last picture more of what your looking for? :o

Okay I will wait for your update.

Bye for now!
Neil

« Last Edit: November 10, 2009, 09:30:27 PM by wheelyneil »
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #98 on: November 11, 2009, 01:31:06 PM »
Hi Neil,


I reset the test gen circuit to as close to 80Hz as possible.
Yes, the period looks fine now.


Just so you know VR1 gave me no adjustment control, If it did it was so little I could barely detect it and no way could I decrease the high by half. R5=~65k, I checked VR1 it had full range but still no control over the circuit. I swapped out C2 also.
The formule for the period where TP3 is high is:
  ln(2)*R * C

Where
  ln(2) =~ 0.693
  R (=R5+VR1) = from 68k to 115k
  C (=C2) = 100n
  So the high part of the period should be settable from 4.7ms to 8.0ms.

If the components holds these (approximate) values and the 4093 is working, it will be settable from (approx.). The transitions of these 4.7ms to 8.0ms should be nice vertical lines.
Any other case, something is wrong.

If your probes have a 1:10 or 1:100 setting (by a switch in the handle), then switch to that and adjust the V/div. accordingly (to 0.5V/div or 50mV/div) - this will reduce the amount of loading from the 'scope by the same amount.


One way to verify the function of the 4093 alone is like this:
  • Put the probes that controls the trigger on TP2
  • Set the trigger to NEGative trigging and adjust for reliable triggering
  • Put the other probes on TP3
  • Remove C1 from the circuit
  • Each time TP 2 is touched to ground (with a wire), TP3 will go high for 4.7ms to 8ms (depending on VR1)

How does that look on the scope?


Okay Here is something, when I removed the dual trace signal from the scope and dropped the TP2 it changed the freq of TP3's "HIGH" by about half.
You can see it in the last picture .  It looks like that wave is pretty close to 80Hz. The scope was set at 5v/div and 5mS/div Hope it helps, that you know this info? :-\
It sure helps. Perhaps it's overshoot from the beam when it switches between the traces.


Is the last picture more of what your looking for? :o
Unfortunately no, I'm looking for something close to what I drew in the PDF.
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #99 on: November 11, 2009, 05:59:31 PM »
Soren

Well I think you will be happy with this wave form. I found the problem. After pulling every gray hair and eyeballs laying on my desk I decided to check for continuity and sure enough the wire from pin 5 to pin 8 was internally broken.

As soon as I replaced it all adjusting could be done I made sure test generator 80Hz and set TP3 high and low to equal time.
 
Also I sent a picture of TP4 just incase TP3 was okay. ;D

After TP3 I used R6-R7 33k and Q2=new 2n4401 C3 C4 440nf then hooked scope to TP4 and this is what was on screen.




Take care

Neil
« Last Edit: November 11, 2009, 09:37:51 PM by wheelyneil »
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #100 on: November 12, 2009, 06:17:44 PM »
Hi Neil,


Well I think you will be happy with this wave form. I found the problem. After pulling every gray hair and eyeballs laying on my desk I decided to check for continuity and sure enough the wire from pin 5 to pin 8 was internally broken.
Now we're cooking ;D

 
Also I sent a picture of TP4 just incase TP3 was okay. ;D

After TP3 I used R6-R7 33k and Q2=new 2n4401 C3 C4 440nf then hooked scope to TP4 and this is what was on screen.
TP3 is perfect now  8)  8)  8)

When you measured TP4, Was the input selector in AC mode then?

With a 50% squarewave, the mean of the trace should be at V+/2 (perhaps a wee bit lower, as the outputs of the 4093 might not go all the way to the rail).
With eg. 25% of the waveform positive, TP4 should be ~25% of B+ and so on - that's how the part of the circuit you have build so far are gonna convert the RPM pulses into a proportional DC voltage that will be controlling the PWM output to the servo (with the part of the circuit still missing).

So, TP4 should reside at around +6V, but the scope trace looks like you measured in AC mode (which will have its mean at 0V).
Besides this, the 2N4401 is not the best choice (low h_FE at low currents), so you might wanna increase the values of C3 and C4 by at least a factor 5, but anything up to, say 10µF or whatever you have (of a reasonable physical size) will do.

But TP4 needs to show around half of B+ and it might be a good idea to make that happen before anything else.
First check that the input selector is in DC mode.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
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Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #101 on: November 12, 2009, 07:16:39 PM »
Hi Neil,


Just saw that you're on-line, so I'll go to the chat for a (short, as I'm less than 4 hours from the alarm clock) while, in case you have any quick questions.
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #102 on: November 12, 2009, 09:41:00 PM »
Hi Soren

Sorry I missed you last night while you were here. I was pulling my hair out trying to fix this bugger. :-[


Well we have a problem. I have tried a lot of different things to achieve the wave form you are looking for at TP4.

Here is what has happend so far, I changed the Q2 to a mps2222a and both  C3 and C4 changed to 1uF this is all I had to choose from. Which didn't help the way the wave form looked or acted.

So I decided to insert the Tp3 signal in at a different locations.

I have sent a snip of the circuit change to achieve the wave form and amplitude needed.

Now I don't know if it was the right thing to do but it was the only way a could reach what we were searching for.

If I tied Tp3 in series to the collector of Q2 it ruined the wave But if I applied the Tp3 to the node between R6 and R7 the signal looked like your drawing and was at Approx 6volts with 50% of the wave.


Here are a couple pictures  the first is with Tp3 tied in series with collector of Q2.

 And the second picture is the wave with Tp3 tied to the node between R6 and R7

THE signal in the pictures are at TP4 location in both cases.

Soren I hope this wasn't a bad thing?  If so I am sorry but as I said with a lot of trying it was the only way to get the job done.
If you can get me there another way please help me.

Best regards
Neil
« Last Edit: November 13, 2009, 12:22:21 AM by wheelyneil »
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Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #103 on: November 13, 2009, 03:56:24 AM »
Hi Neil,

Well we have a problem. I have tried a lot of different things to achieve the wave form you are looking for at TP4.
[...]
I have sent a snip of the circuit change to achieve the wave form and amplitude needed.
Oh, I'm the one who have made a blunder here - sorry, i should have looked a little closer at the traces yesterday and I would have seen the problem (no supply when the 4093 output is at 0V :-[
The attached file should remedy that (for some reason, I can't ftp out of the hospital presently) - don't do it the way you did (you place a large capacitive load on the 4093 output).
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #104 on: November 13, 2009, 06:58:37 AM »
Hello Soren

I just want to drop you a note and say thanks for sending me a option on how to fix the problem.

My Daughter is very sick today and needs my help to care for my 16 month old Grandson, so I will try later today to fix the circut.

But you will more than likely be sleeping when I get to it.

Neil
Take care
Neil

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #105 on: November 13, 2009, 03:04:35 PM »
Hi Soren

I got a few minutes and went to get the caps and resistors needed. I put them in and here are the results.

Not good on TP4 as far as looking as it should.

So give me a good kick if I need it, and I have switched the Q2 out with all of the small to medium signal NpN's I have Maybe I have to order a different kind?

Let me  know what you think and Ill get back as soon as I can .. Things are a little crazy the next few days for me.

Thanks again Soren

Regards
Neil
« Last Edit: November 13, 2009, 03:09:17 PM by wheelyneil »
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Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #106 on: November 14, 2009, 04:17:08 AM »
Hi Neil,

Not good on TP4 as far as looking as it should.
I really wonder how you're getting this "free energy" ;)
On TP3B, I guess the amplitude of the triangle waveform is a bit under 1V(?) with an average around 6V.
When you feed 6V into the next part, the transistor will drop at least 0.7V, so I don't see how you can end up with ~12V - That's breaking the Laws  of Thermodynamics ;D

Seriously... This cannot be happening, unless you have something else supplying TP4.

For the rest of the measurements (up to the point where we have a reasonable stable "DC"), when measuring the AC amplitude, try changing the settings to:
Input selector in AC mode
Increase the sensitivity to 0.2V/div
Decrease the timebase to get the extremes (top bottom) of the curve closer together
Move the trace vertically to get a good amplitude reading.


Let me  know what you think and Ill get back as soon as I can .. Things are a little crazy the next few days for me.
At least you get to spend some quality time with your grandson :)  Happy recovery to your daughter. Take it easy with the electronics - Family comes first!
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

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #107 on: November 14, 2009, 04:50:30 AM »
Here's an updated schematic: http://That.Homepage.dk/PDF/V8SG_4,0.pdf
And here's a file that you may find usefull (or not) http://That.Homepage.dk/PDF/Scope_Photo_Tips.pdf
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #108 on: November 16, 2009, 11:13:38 AM »
Hey Soren

Just wanted to say hello and tell you I think I am ready to get back to work on this project. Family is better Girl friends Been pacified and I am free for a while .

Must say those smooches I got off my grandson were pretty sweet! :P

Also Just to let you know I had to pick up a large proto bread board, it was getting very crowded on a 500 jumper location with the Test Gen Circuit on it and the Gov Circuit.
So I jumped up to a 2600 hole with  dual power input clips, so I will be rewiring and making room so I can see better, too many jumper in a tight space.

Quote
OH yes! I forgot. Didn't you now that I was the one and only MAN "numbskull"to be able to get more energy out, then what I put in?  Oh Yes all you have to do is pull the little red VAR button on the vertical volts division and you can get a least 100% over unity................ :D


Man when I seen that on the screen i felt like sticking my head in the ground :o and for me  not to stop and look at it and what I was showing you, knowing good and well at least .6 volts would have been pulled over the Q2. Anyways sorry for such a blunder.


So I will rewire a few things get a clear head and get you some info probably later tonight my time

Take care

And allways Best regards

Neil
Take care
Neil

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #109 on: November 17, 2009, 10:01:12 PM »
Soren

Sorry I have not updated I am having some trouble with the circuit and trying to find out what it is?

I think I am having serious power supply problems. I am going to get a 12v batt set up so maybe it will clear things up.

I just keep getting all kinds of strange noise on the signal when I hook Vdd to R3 R4 and D1. TP1 and TP2 look crazy, but when I pull vdd off I get a clean signal from the test gen signal .

 And thats with it not connected to the 4093.

 I will change the power source and then see what we get.

Take care

Neil
« Last Edit: November 17, 2009, 10:11:03 PM by wheelyneil »
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #110 on: November 18, 2009, 04:16:14 AM »
Hi Neil,

I think I am having serious power supply problems. I am going to get a 12v batt set up so maybe it will clear things up.
Do remember to have a fuse (say 2A to 5A Slow-Blow) in-line with B+, close to the B+ terminal, if you're using a car battery.
If you have/find a spare PC-supply it could be used.

I just keep getting all kinds of strange noise on the signal when I hook Vdd to R3 R4 and D1. TP1 and TP2 look crazy, but when I pull vdd off I get a clean signal from the test gen signal .
If you're using the exact same setup as on the smaller board, it is probably a simple (however hard to spot) wiring mistake.
If you didn't have the test generator on the same supply previously, the solution could be as simple as adding a cap of say 1..100 nF (as close to the V+ pins as possible ) to each IC as possible, as each time the 555 output changes, it will give some noise on the supply line.

But re-check the wiring with a magnifier first, it's a classic that gets us all every now and then  :-[
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #111 on: November 18, 2009, 09:56:32 PM »
Hi Soren

Quote
If you have/find a spare PC-supply it could be used
I picked up a old 250 watt PC power supply today, I'll pull the one leg to ground and she should fire right up.

I am rechecking the wiring and going over everything a little at a time. I hope

I can have it running right shortly.
« Last Edit: November 18, 2009, 09:58:39 PM by wheelyneil »
Take care
Neil

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #112 on: November 20, 2009, 02:53:15 PM »
Well Hello Mr Soren

Did you think  I gave up? ;D

I thought I was going to have too! I could not find the problem for a long time.

i am now using a fused 350 watt PC power supply and it seems to work great.
 
Then I remembered about grounds making circits go nuts so I went along and made sure they were rock solid and together and wallah it was all better.

Anyways here is what I have for you, I had to make a couple changes, Don't roll your eyes...... ::)

The problem I was having was after I cleared the noise I was having on the circuit caused by bad grounds, was when I reached TP3B and put in the next part of the circuit.

 The 1uF caps flattend the signal so there was no wave form  I had to use  2 - 10nF for C3 and C4.

Here are the pictures of the wave forms I hope they will work for the project? ;D
« Last Edit: November 20, 2009, 04:02:20 PM by wheelyneil »
Take care
Neil

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #113 on: November 20, 2009, 02:58:02 PM »
Here are the rest of the pictures up to TP5
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #114 on: November 20, 2009, 07:45:40 PM »
Hi Neil,


Did you think  I gave up? ;D
Not at all.


Anyways here is what I have for you, I had to make a couple changes, Don't roll your eyes...... ::)
I'll do my best ;D


The 1uF caps flattend the signal so there was no wave form  I had to use  2 - 10nF for C3 and C4.
::)
Oops Sorry  ;D

You do know that the purpose of this part IS to "flatten" the signal (make it very close to DC), right?

Please swap in the 1µF again and then measure:
- The DC level, which should be around the 6V mark
- In AC mode, crank up the sensitivity (V/div) until you either get the waveform to fill at least 5 or 6 divs  or reach the max. sensitivity and then tell me the amplitude (or snap another photo of each measurements annotated with V/div).
For the latter, please slow down the timebase to get, say, 3 to 10 full periods  in each horizontal division.

When this is done, I think this part is finished and only needs to be checked for mean voltage out vs. frequency in (from eg. 75Hz to 85Hz), Input on one trace and the output on the other.
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #115 on: November 21, 2009, 01:34:50 PM »


Hi Soren

Quote
You do know that the purpose of this part IS to "flatten" the signal (make it very close to DC), right?

Yes

  The reason I was trying to hold the wave form as close to the diagram was I wasn't sure, if you need to tap off one of the test points for another part of a circuit. I know you are trying to get as close to DC for the servo.  
And that where trying to make the voltage increase and decrease with freq input change. I thought thats what we were trying to do if I am thinking wrong throw me a DOG BONE  ;D So I do understand ;)

Quote
Please swap in the 1µF again and then measure:
- The DC level, which should be around the 6V mark

It is done and it is very close to 6volts.

Quote
In AC mode, crank up the sensitivity (V/div) until you either get the waveform to fill at least 5 or 6 divs  or reach the max. sensitivity and then tell me the amplitude (or snap another photo of each measurements annotated with V/div).
For the latter, please slow down the timebase to get, say, 3 to 10 full periods  in each horizontal division.

Her are the pictures from 50mv to 5mv/div   on the AC reading and 10 ms/div time. if you need me to change the pictures again let me know  I hope you can see the form well enough  if not let me know and I'll have another go  at it :P

Quote
When this is done, I think this part is finished and only needs to be checked for mean voltage out vs. frequency in (from eg. 75Hz to 85Hz), Input on one trace and the output on the other.

As soon as you say go I will get input and output readings  ;)

But just to let you know  I did hook up both channels and when I had a input wave and output wave I fully swept VR1 on test gen circuit the output voltage only changes about .2volts. Out put signal is set on the 1v/div scale and goes Ov to .2volts.

The Test gen circuit time is changing from about 78.13HZ to 81.97HZ I cant get a 10 HZ time change from it.
« Last Edit: November 21, 2009, 01:37:54 PM by wheelyneil »
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #116 on: November 21, 2009, 03:23:38 PM »
Hi,

But just to let you know  I did hook up both channels and when I had a input wave and output wave I fully swept VR1 on test gen circuit the output voltage only changes about .2volts. Out put signal is set on the 1v/div scale and goes Ov to .2volts.
0..200mV?
What happened to the "close to 6V"?


The Test gen circuit time is changing from about 78.13HZ to 81.97HZ I cant get a 10 HZ time change from it.
If you change C1 (test generator circuit) to 33nF and R1 to 200k you should get a large enough range, even with wide component tolerances.

I think we can say that the "DC" is OK for now - 20mVpp shouldn't be a problem, so let's get the test generator to cover a slightly larger range for the next bit of testing.

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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #117 on: November 21, 2009, 06:12:51 PM »
Hi Soren
Well we wont talk about the missing 5.8v from last reply. It seems the scope operator was having a lttle to many 7&7's while driving missed a switch and crashed the voltage----------- :-[ :o ::) :'( ;D


Added 233k R1 and 22nf C1 now I have a range of 71.5 to 88.9 Hz
Now when I sweep VR1 on gen tester I get about a 2v swing from the output, 4v at min freq to 6volts at Max freq

Here are the pictures from the Min 71.5 Hz and the Max 88.9 Hz with input and output signals together.

Hope this is better.
« Last Edit: November 21, 2009, 06:24:34 PM by wheelyneil »
Take care
Neil

Offline Soeren

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #118 on: November 21, 2009, 07:12:04 PM »
Hi Neil,

Well we wont talk about the missing 5.8v from last reply. It seems the scope operator was having a lttle to many 7&7's while driving missed a switch and crashed the voltage----------- :-[ :o ::) :'( ;D

Yeah, I figure it must have been the 7-up  :P


Now when I sweep VR1 on gen tester I get about a 2v swing from the output, 4v at min freq to 6volts at Max freq

Here are the pictures from the Min 71.5 Hz and the Max 88.9 Hz with input and output signals together.

Great.

The next (last) block is here: http://That.Homepage.dk/PDF/Servo_Control_V2c.pdf in the experimental varsion.If you'd rather do the 555 solution, please say so, but this is what you'll learn the most from.

A few values is missing (I'll correct that tomorrow), but anyway, see if you can recognise the function of the various parts and figure what's going on and what's causing what, before I explain it - that way you'll get into it much better than if you just get it laid out I think.
It can be build in blocks, but some of it cannot be tested completely until finished, as it is one control loop. It can however be verified in steps while progressing.

The output is supposed to drive the servo directly (it's got a supply for the servo of ~5.6V) and just need a 3-pin connector for it.

When all is finished, we have to get all the corrections and the substitutions you made and draw it all into one schematic (and make a PCB layout).
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

Offline wheelyneilTopic starter

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Re: Question! and Help I need to build a v8 engine servo motor governor
« Reply #119 on: November 21, 2009, 09:15:24 PM »
Soren

Experimental Version! is my pick 8)

If you dont mind? Seeing it might take a little more time?
Take care
Neil

 


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