Servo driver?

[hugh hargett]

http://youtu.be/q5IECWdPqYQ

What more you need? :blink:

Simple stuff meaning not that those that dont know how to do it are dumb but simple as in they can learn to do it easy. the speed of the servo can be easily changed in the code the pause statement in the code speeds up or slows down the loops and the "duration-25" in the code dictates the size of the steps it moves in large steps or small by changing (25) in the statement. The endpoints too can be set in the code

 

[hugh hargett]

David, heres the first example ive seen of code for a arduino based servo controller

http://arduino.cc/pl...gleServoExample

Screenshot of program terminal with debug monitoring: you can see if you compare the code on the screen to the code I posted earlier you can see the changes I made so the servo would travel the entire 180 degrees

 

[hugh hargett]

Arduino schematic for servo hookup i dont have to be these exact pins but yoh have to code the pins you hook yours up to.

arduino hookup.bmp

sorry its not that clear

code for two buttonscode for arduino.txt

the schematics shown are not for this code they both are just examples

Thats it for my contributions for today. Feed on it.

Hugh

 

[Tim_Duggan]

I decided to take the plunge and ordered an Arduino nano yesterday for my little project. Hopefully it's not too distracting in terms of my other builds that are on the go......

 

[dwilfong]

I decided to take the plunge and ordered an Arduino nano yesterday for my little project. Hopefully it's not too distracting in terms of my other builds that are on the go......

Hay Tim I am ordering one this week also to play with.

Maybe we can pull each outers hair out messing with it............ that did not come out right :huh:

Any who let us know how loading the drivers go in the computer to work with it.

 

[Tom Foley]

Wow ..just put fuel in it and run it on the real lake ..not the Virtual Lake !! :lol:

 

[Tim_Duggan]

David,

I'll let you know when I get my hands on it and find some spare time to look into it. As mentioned in an earlier post, I've set up the radio for manual switching on channel 4 initially - Automation can come later - but I've made the first step to going from manual to auto in buying the nano. Learning the coding might take a bit of time, but I guess these things are friendly enough that a boat or a pond are not essential to test it.

Do you have a preference for a temp sensor?

 

[dwilfong]

David,

I'll let you know when I get my hands on it and find some spare time to look into it. As mentioned in an earlier post, I've set up the radio for manual switching on channel 4 initially - Automation can come later - but I've made the first step to going from manual to auto in buying the nano. Learning the coding might take a bit of time, but I guess these things are friendly enough that a boat or a pond are not essential to test it.

Do you have a preference for a temp sensor?

I have a few of the Eagle Tree ones on hand. nice and small. will see what thy will do when I start messing with it.

Like you said writing the code will be a pain to learn. will take some time to get the hang of it.

 

[Tim_Duggan]

Got the Arduino nano today! https://www.intlwaters.com/gallery/displayimage.php?pid=17721&fullsize=1

Arduino + HS50 servo + servo mount = 17 grams.

 

[dwilfong]

well I finally got to the local surplus store an picked up every thing to build a temp control.

Going to use a 555 chip to control the servo. here is the circuit i will use.

I will replace the 100k pot with a 100k thermal resistor I found.

This will run a very small servo and the Perry valve.

Will See how the build goes.

Here is a pic of all the components. the small one on the right is the temp sensor

 

[Tim_Duggan]

Cool David. Let me know how it goes for you.

I've been playing with the arduino, learning the code, but haven't got as far as putting anything in a boat.

 

[dwilfong]

http://www.youtube.com/watch?v=lyJNPOTSTBE&feature=youtu.be

Well got it all together and it works.

All most have the servo and valve mount done will post a pic real soon.

 

[dwilfong]

http://www.youtube.com/watch?v=VfExPJexujc&list=HL1337537959&feature=mh_lolz

Her you go.

 

[Tim_Duggan]

Great Demonstration David! I was impressed at how quickly the response shows up on the flowmeter! obviously the engine temp is not going to escalate that fast but it's good to know that the system is capable of acting very quickly!

It's currently working in a way solely reliant on the input from the thermistor to change the valve in a linear fashion. While this will work well to build temp quickly - it's not specifically designed to maintain a particular temp. From what I can establish, this can only be fine tuned by tweaking the valve relative to the servo. What about adding a small screwdriver type pot in series with the thermistor to allow a little tuning on the fly?

Tim

 

[RodneyPierce]

David, how cool is that? Good job man. Pretty neat!!

 

[Ian Inverarity]

David, very nicely done!

 

[Charles Perdue]

I knew all of the time that you could do it.......

Charles

 

[dwilfong]

thanks guys.

This was my Sunday morning take a break from the eng building project.

I have a 100k pot that is smaller than the chip that I used to see how the servo would move and to tune the valve. This can be put in line with the thermal resistor to tweak it if needed. but the way the Perry valve is made you can just turn the disk with the slot on it to adjust the amount of flow to any thing you need.

I will do a bench test with it on the eng and run it on the stand hooked up to my water pressure rig. the adjustable water pressure regulator on the system can set the pressure any where I need.

So how much pressure do you all think a boat running will produce?

With the Eagle tree set on live mode I can check the temp in real time as you run the test. that way you can fine tune it as you run the eng on the stand with the disk on the Perry valve.

I almost Pissed my paints when I saw how good it worked.

Some time the simple things work the best. Heck of allot easer than writing code.

Going to try making one that will work with a K coupler next to run the needle with ex gas temp.

David

 

[Tim_Duggan]

So how much pressure do you all think a boat running will produce?

Good question, and I've been contemplating this myself. As Charles eluded to in an earlier post - this is a variable. Faster you go, the more water is forced in. As the engine warms up, it's ability to go faster improves. Secondly, as the needle valve acts as a restriction, it creates additional pressure between the pick-up and the valve.

These are some of the reasons why I wanted to go with a dual position "switch" rather than a progressive movement of the servo.

With the Eagle tree set on live mode I can check the temp in real time as you run the test. that way you can fine tune it as you run the eng on the stand with the disk on the Perry valve.

Maybe testing intitially in a boat with the valve set to a less restrictive setting and monitoring the time taken for the temp to stabilise would be useful to establishing a benchmark?

Some time the simple things work the best. Heck of allot easer than writing code.

Agreed - but when we get to the stage of multiple things being run autonomously, a logic controller will work out smaller/ lighter / neater/ more user friendly than multiple 555 circuits. Cooling regulation is just the first step!

Going to try making one that will work with a K coupler next to run the needle with ex gas temp.

David

Looking forward to that - I think that one may prove to be slightly more difficult given all the variables such as fuel pressure.

I'm looking into onboard glow drive at certain throttle %'s switched via a MOSFET using the PWM signal fron the throttle servo as the trigger - found a nice little FET board to do it and a similar sized IC to the 555 to read the PWM signal and switch the FET on or off. This does require code tho'.

Tim

 

[dwilfong]

Tim

Yes the nano is the end goal.

As far as multiple circuits thy can all run in one chip 7555.

Don't worry about the pressure in the line it won't hurt any thing. Have my 1.01 restricted to a .080 orifice and it works fine at 90MPH.

There are a few glow drivers already out there that will adjust to the plug heat.

As far as fuel pressure it will not mater it will do what it dose now control the flow at different RPM's.

The system will work off the 3rd channel needle it will just make adjustments as far as the needle will travel.

This will all depend on the needle and how much the flow will change with the adjustment.

You will have to be in the ball park to start and the needle will only be able to adjust very little. It will not take much to change the ex gas temp.

At low speed it will run very lean to try and raise the temp. this will be a good thing as the throttle will be sharp as a tack.

It all sounds good on paper will see if it pans out.

so hows that nano pretty easy to wright the code? will get one it is on my list. heck thy have them at Radio shack down the street.

It is just easer to experiment with this chip for now. built this set up in less time than writing one line of code.

David