Tuesday, April 26, 2016

New Weekly update

It turns out I have an audience of one. It's been suggested that I explain the steps better have a larger view of the overall project. To accomplish this I will attempt to make each segment of the process duplicatable. I've been heavily considering making short videos to go along with the text. He will come to find that my video editing skills are even worse than my spelling.

Tuesday, April 12, 2016

Air systems optical encoder

The servo does not have a built-in encoder :-(, this has proven to be an inconvenience because the servo motor for the era regulation does not move linearly with increased load. The optical encoder will improvise for this sluggish movement.

The key to every mystery is a simple as finding data points. More data points you have: the more he will know about the mystery.

My mystery is also battle, I cannot move at a high radial frequency because my sample rate is too slow and resolution relatively unknown which I will get to momentarily. I can designate a separate microcontroller to the optical encoder, by servo with an encoder, or decrease my resolution of the encoder but keep it in with my desired accuracy.

How accurate do I need it? Back to that whole making data points to solve the unknown. Here it is see Figure 1:


Figure 1: pressure versus degrees of rotation by the servo.


My graphics in figure 1 seem to me missing some crucial data this can now be found in Table 1.
Radial degrees
Test 1 atm
Test 2 atm
Test 3 atm
1.0
1.1
1.1
60°
2.1
2.0
2.0
120°
3.6
3.5
3.4
180°
5.1
4.8
4.9
240°
6.6
6.4
6.3
300°
7.8
7.6
7.6
360°
9.1
8.6
8.8
420°
10.5
10.1
10.3
480°
11.8
11.6
11.7
540°
 n/a
 n/a
13.0
600°


14.4
660°


15.9
720°


17.9
780°


19.4
840°


21.0
900°


22.6

Table 1: radial degrees first pressure plot.


There are some data points but I am limited by my temporary pipe system which is only supposed to handle 8.2 ATMA (~100psig). The second it as a pressure test shortly after reaching the 16 ATMA I had a joint start leaking air.

Test 1 may have some extra and accuracy from my air tank rotating.

Test 2 corrected errors than the of occurred and test one.

Test 1 and 2 were only brought slightly above the maximum suggested pressure.

Test 3 was pushed further than the maximum suggested pressure mainly the first third visualize the linear reality of the pressure regulator.

Conclusion I will need a minimum resolution of 87 nooks. Note: 0.1 ATM is this lowest acceptable resolution as used in this calculation.

Case Test 1: 480°/10.8atm = 4.44°/0.1atm =>360°/4.44° = 81 nooks.

Case Test 2: 480°/10.6atm = 4.53°/0.1atm =>360°/4.53° = 80. nooks.

Case Test 3: 900°/21.6atm = 4.17°/0.1atm =>360°/4.17° = 87. nooks.


I will go with Case Test 3 results, because they are the least favorable. To further simplify future arithmetic and to have a little above the minimum I will go with 100 nooks.

Here's a link to a site which generates optical encoders:http://www.bushytails.net/~randyg/encoder/encoderwheel.html

The could be some small improvements to the site but I'm not about to write one myself so I'll deal with it and imagine you'll do the same. After plugging chunking and redoing I came up with my optical encoder see Figure 2



Figure 2: optical encoder image with 100 steps.

How does an optical encoder work click (here)