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Heliostat Projects / Re: DIY Worm Gear Based Heliostat Design
« Last post by luiklodwig on February 01, 2018, 01:29:43 AM »
Thanks! I tired my best to make the machine as mechanically accurate as I managed.. it turned out that the base is not exactly parallel to the fork where the mirror is mounted but when you play around with a level for a while it still get's sort of straight ;)

another video showing speed with motors @20RPM
https://vimeo.com/253754632
PW: speed
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Heliostat Projects / Re: DIY Worm Gear Based Heliostat Design
« Last post by Gabriel on January 30, 2018, 05:38:16 PM »
Wow! That is really accurate. That's the hardest part it seems is making the machine be precise.

I'm glad you got it working. :)
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Heliostat Projects / Re: DIY Worm Gear Based Heliostat Design
« Last post by luiklodwig on January 30, 2018, 02:21:37 PM »
I made a timelapse of my heliostat, I'm very happy with the precision, but It's my first working heliostat ...

Distance between target and heliostat was about 6-7m
https://vimeo.com/253500405
(Password: heliostat)

Thank you so much Gabriel for your wonderful work!
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Sun Tracking / Heliostat Program Discussion Board / Re: heliostat doesn't move
« Last post by luiklodwig on January 23, 2018, 02:11:16 PM »
well, for someone who might have a similar problem:

It actually helped to "ask" the switch twice if it was hit

I changed the reset section in the "Functions" Tab of the programm.

Code: [Select]
//This code resets the machine on the limit switches
void findLimits(int altOrAz, int motorDirection, float limitAngle){
  if (altOrAz==1){
    searchForLimit(limitAngle, altitudeDirPin, altitudeStepPin, altResetSpeed, altLimitPin, altitudeMax, motorDirection );
  }
  if (altOrAz==2){
    searchForLimit(limitAngle, azimuthDirPin, azimuthStepPin, azResetSpeed, azLimitPin, azimuthMax, motorDirection );
  }
}
void searchForLimit(float limitAngle, int DirPin, int stepPin, int ResetSpeed, int LimitPin, long maxResetSteps, int motorDirection){
  long x;
  int whichDir;
  if (motorDirection!=0){//A motorDirection of 0 will skip the reset 
  if (abs(limitAngle) != limitAngle){whichDir = 1;}else{whichDir = -1;}
  if (motorDirection*whichDir != 1){digitalWrite(DirPin, LOW);}else{digitalWrite(DirPin, HIGH);}
    float MotorDelay = ( 1000000 * ( 60 / (steps * ResetSpeed) ) ) / 2;
    while(x<maxResetSteps){
     digitalWrite(stepPin, HIGH);
     delayInMicroseconds(MotorDelay);         
     digitalWrite(stepPin, LOW);
     delayInMicroseconds(MotorDelay);
     //////changes
     if (digitalRead(LimitPin)==HIGH){
       delay (5);
       if (digitalRead(LimitPin)==HIGH){
       x=maxResetSteps;}
     }
     x+=1;
   }
  }
}
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Sun Tracking / Heliostat Program Discussion Board / Re: heliostat doesn't move
« Last post by luiklodwig on January 22, 2018, 01:48:42 PM »
Hi everybody,

Because I wanted to have everything clean and nice, I decided It might be a good idea to put the arduino in a case with the buttons installed in a clean front panel and put all the 12 wires from the arduino control to the heliostat machine together in a single 12 core cable of 5 meters length. I did it and I'm happy with how tidy everything looks now, but unfortunately I'm having a little bit of troubles with the heliostat now. Sometimes it seems that (especially the alt motor) stops before hitting its limit switch but everything behaves as if it was hit, sometimes it just moves as if it was already sitting on the switch when I turned it on; sometimes the machine starts moving after reset, sometimes it doesn't...

I use 2 different input lines for alt and az limitswitches and each has it's own ground wire...i'm not sure what kind of resistors I'm using right now, but maybe I should use different ones now that I have the 5m of cable?

any ideas would be appreciated :)

edit: ok so I recon that adding more resistance is not going to help against this noise or whatever is happening inside of my cable... in another forum on a similar issue someone suggested to read the switch twice to make sure it was actually really triggered, maybe I'll try this then...If I find the right place to do that :D
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Heliostat Projects / Re: DIY Worm Gear Based Heliostat Design
« Last post by luiklodwig on January 17, 2018, 03:13:41 PM »
Hi Silverbrewer, sorry for the late reply.

I'm currently rewiring the whole thing to have just one cable from heliostat to arduino-control and finalising the mechanical aspects as good as I can, so I can't really do a video right now because it just not in a working state right now. I should add maybe that I am not planning on a sort of permanent installation of my heliostat so weatherproofing and the likes are not my top priority. I think that the gears should hold up rather well since they are made to be used in  harsh conditions I guess, but the waterproofing of the motors would be essential. Maybe a mechanical solution were the electronics and drive system is protected in a single case would be easier to be made fit for real weather.. Concerning speed and scaleability. I was surprised how fast the system goes.. when I last tried, i set my motors to 60rpm and it felt  too fast for me so I set them back to 20rpm for the testing time beeing :) The power of the motors in combination whith those gears which give something like 1:55 is also quite impressive, so I think that it is safe to say that a glass mirror of 50cm in diagonal would be no problem if the bearing is good and you could probably go larger if you would use an acrylic mirror or sth.

I can try to post a video once I get the thing were I want it to be, but I think I'll just need a few days do get it done now..
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Think Tank / Re: Can we learn from this machine based Arduino app?
« Last post by Gabriel on January 16, 2018, 02:37:11 PM »
It has been on my list to something similar with an actual computer interface. It's just finding the time to do it that is the hard part. There is honestly a lot that I want to overhaul to get things up to date with the times. It may have only been about 5 yrs since the program was more or less finished, but electronics and programming libraries change quickly.

There is actually someone working on something similar to what you mentioned, but it isn't quite ready for release yet. I am actually testing it out on my end, but I haven't gotten a hold of it yet. Hopefully I will be able to say more relatively soon.
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Think Tank / Can we learn from this machine based Arduino app?
« Last post by Silverbrewer on January 16, 2018, 01:15:15 PM »
I am new here, an Arduino novice, and was surprised at how god damn fiddly downloading the program was!!

My comparison is with the Arduino based project I am about to describe which involves downloading a free app, connecting the bits, calibrating the whole shebang and hey presto.
While I assume that making an app to run an Arduino project is not for the feint hearted, the cerebralmeltdown mantra is that you are looking for the learning experiance, so take a look at it, as the app is a very good looking interface, and a similar sort of thing could do wonders for the Sun harvester Project.
Both you and Yuriy are in the States, so perhaps as sole designers of two really good projects, a start would be to do a shield trade!!!   
Also, it is a no brainer for anyone with a Taig lathe :0)

So here goes...

The last Arduino based project I made was for controlling a digital read out (DRO) for a lathe or mill.
It will need one of you brainiacs to fathom how it has made Arduino control so easy, but in a nutshell, it is a free Android only app that bluetooths to anarduino with a suitable shield, that is connected to digital measuring slides on your lathe or mill, and gives you fantastic control options with no backlash. It is called "TouchDRO" and is easily found on YouTube or wherever.

I was so impressed with the one I fitted to my lathe thatI straight away made one for my mill.

I am lucky enough to have a Boxford A.U.D. screwcuting lathe and an Elliott Junior Omnimil, and I can control each machine from the one tablet. The lathe has readouts on the bed and cross slide, and the mill has readouts on the Quill, bed, saddle and knee, and it has transformed beyond measure how easy it is to use the machines, making PCD hole arrays, converting from Metric to Imperial measurements etc a doddle. 
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Heliostat Projects / Re: DIY Worm Gear Based Heliostat Design
« Last post by Silverbrewer on January 14, 2018, 07:36:56 AM »
Well shiver my Timbers!!!! How the hell did I miss Luiklodwig's post about 3" above this one???
He has already done exactly what  am going on about.
Luiklodwig, could you post a video showing its max speed and enlighten us on how you think it will cope when bigger, and out in the elements.
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Heliostat Projects / Re: DIY Worm Gear Based Heliostat Design
« Last post by Silverbrewer on January 14, 2018, 07:03:56 AM »
I am just starting out on my experiments, and so far am looking at using the gearboxes on front windshield wiper motors.
Just pick a common make that is cheap. Most all will be steel worm and plastic worm wheel nowadays, though if you find one with full metal construction then even better. Both of mine have the motor shaft running through a ball bearing race.
I have taken them both apart, and cut off the motor armature and removed the commutator segments. This gives me an 8 mm dia shaft about 12 mm long going into the 61:1 ratio gearbox. Using ebay flexible shaft couplings, it is my intention to first try a nema 17motor, which is small enough to mount to the shaft stub, and be able to re fit the original motor cover, and if that proves too feeble, I will fabricate a motor mounting plate that allows me to fit a nema 23, and bin the motor cover.

It surprises me that this worm gearbox can be rotated by hand on the output shaft, as I was expecting it to lock against back driving forces. Perhaps I will go through two gearboxes in series if back driving is a problem.

Most stepper motors can be had with integral planetary gearboxes, but they are a tad pricey. Good planetary gearboxes can be had from cordless drills, but then you have to come up with a connection method for the input drive. not impossible though. First, lets see what sort of gear reduction ratio best suits our needs.
In a week or so I will cobble together a crappy video and post it on YouTube so this verbal ramble makes sense.

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