#garfield Logs

Jul 14 2021

12:19 AM rue_mohr: na
12:27 AM rue_mohr: the programmer cant detect the device chain
12:27 AM rue_mohr: aandrew, ooo
12:28 AM rue_mohr: Is there much good stuff there? did you know a motor that a motor changing angle at 6 degrees/ms is doing 1000rpm?
12:29 AM aandrew: I'm going back over my early career training
12:29 AM aandrew: this is heavier on the math which I didn't have a good handle on before
12:51 AM rue_mohr: hmm
12:51 AM rue_mohr: the 2HP steam engine needs 1L/sec of steam
12:51 AM rue_mohr: (@200psi)
12:51 AM aandrew: I'll throw them all up on my plex server if you like, I have other stuff up on there too in the same idea (geeky stuff)
12:51 AM rue_mohr: I wonder what safe steam velocities are
12:52 AM rue_mohr: that might be something to play at bedtime
12:53 AM rue_mohr: For superheated steam, the velocities can be up to 40m/se
12:53 AM rue_mohr: so lets say 30m/s
12:55 AM aandrew: yeah I know *nothing* about steam except it's dangerous as fuck
12:58 AM rue_mohr: sounds like a 1cm line would be ok
12:58 AM rue_mohr: so, 1L/sec is 1000cc/sec
12:58 AM rue_mohr: at 30m/s
12:59 AM rue_mohr: 0.3333cm^2
12:59 AM rue_mohr: circle with area of 0.33333cm^2 is dia of 0.65cm
12:59 AM rue_mohr: so, maybe just go up to a 1/2" or 3/4" line
01:00 AM rue_mohr: but it says a lot for how not big the boiler needs to be
01:00 AM rue_mohr: the water supply rate is 38ml/min
01:01 AM rue_mohr: 1L lasts almost 1/2hr
01:01 AM rue_mohr: numbers feel out
01:13 AM rue_mohr: aandrew, I keep running into needing counteracting actuators
01:13 AM rue_mohr: this last time with motors
01:14 AM rue_mohr: you have two motor controllers, one keeps tension on the system while the other "releases" it
01:14 AM rue_mohr: for the opposite direction, they trade roles
01:14 AM aandrew: sure - and doing that with two motors can be tricky because of various systems properties
01:15 AM aandrew: this was a very typical type of issue in industrial control
01:15 AM aandrew: the cheap v/hz motor spinner type drives couldn't do it at all
01:15 AM rue_mohr: so
01:15 AM rue_mohr: with this big cnc, the best actuators I'v got have awefull play
01:15 AM aandrew: but with encoders and a decent drive you can get very, very precise position control
01:16 AM rue_mohr: but if I have two motors keeping the drive under tension, they hold-out the play
01:30 AM rue_mohr: I'm going thru pendent controllers on ali
01:30 AM rue_mohr: I should start making and selling mine
01:31 AM aandrew: yeah the pendant controllers on there are all crap
01:31 AM rue_mohr: the ones that seem ok are $$$
01:31 AM aandrew: might be a nice cottage thing like the spray can holders you've got
01:32 AM rue_mohr: dunno, but I didn't think it was this crazy
01:32 AM aandrew: but there's also this: https://starecat.com/content/wp-content/uploads/me-new-side-project-vs-all-my-other-unfinished-projects.jpg
02:16 AM rue_mohr: the kicad ui is crazy, I wonder who came up with this
02:16 AM rue_mohr: had they never used a cad program before?
02:27 AM rue_mohr: the auto-center-the-cursor-when-zooming is SUPER annoying!
02:28 AM rue_mohr: so, I added 3 leds and 2 buttons to the board for the io that there were no breakout pins for
02:29 AM rue_mohr: some kinda 3.3V regulator and I should be good to go
02:33 AM rue_mohr: oh wait, I got a bga stencil
02:33 AM rue_mohr: where is it...
02:47 AM rue_bed: ok I got a kit
02:47 AM rue_bed: template, jig and solder balls
02:47 AM rue_bed: $15
10:04 AM Tom_L: friday
11:05 AM polprog: i got the 100MHz oscillator working rue!
11:37 AM W1ngs: aww you didn't want to tell me too?
11:19 PM rue_mohr: nice
11:20 PM rue_mohr: what was the winning circuit?
11:50 PM rue_shop2: Cannot find device having IDCODE=494e093 Revision A
11:50 PM rue_shop2: JTAG loc.: 0 IDCODE: 0x0494e093 not found in 'built-in device list'.
11:50 PM rue_shop2: JTAG loc.: 1 IDCODE: 0x49616093 Desc: XC95288XL Rev: E IR length: 8
11:50 PM rue_shop2: JTAG loc.: 2 IDCODE: 0x49616093 Desc: XC95288XL Rev: E IR length: 8
11:51 PM rue_shop2: !!!! I got it!