#robotics Logs

Feb 12 2019

06:30 AM SleepyTurtle: How do you calculate the values for the odometry's alphas and sensor model parameters for AMCL?
08:30 AM rue_bed: dunno
10:20 AM gaze__: hey folks, what's a nice way to make a dirt cheap oven that holds at around 80 celsius for curing 3d printing resins? I was thinking a toaster with a PID loop, but commercial ovens have some degree of insulation and fans and stuff
10:21 AM gaze__: I was thinking of a box made of metalized foam board insulation and then blowing hot air in
10:29 AM deshipu: 80°C is a bit much for hot air, no?
10:30 AM deshipu: I think people use toasters or electric grills for reflow ovens
10:32 AM durrfnotbot: with a PID controller dealie
10:33 AM gaze__: well there's no problem melting solder with a hot air gun
10:34 AM deshipu: that's a much smaller volume
10:34 AM gaze__: it's true
10:34 AM deshipu: and you still don't get very consistent distribution of heat
10:34 AM deshipu: nto sure what the requirements are for resin curing
10:34 AM gaze__: say +/- 10 degrees over the whole folume
10:35 AM gaze__: maybe 5 ideally
10:35 AM gaze__: it's not so strict
10:52 AM rue_mohr: that should be easy
10:53 AM rue_mohr: even my horrid controller does within 10c
11:17 AM Tom_L: i insulated my toaster oven
11:18 AM Tom_L: probably didn't need to but i bet it's a more uniform heat
11:28 AM rue_mohr: I think I stuck some in mine when I redid it
11:30 AM Tom_L: late for work?
11:31 AM rue_mohr: snow
11:31 AM Tom_L: yay!
11:31 AM rue_mohr: and I'm running out of milk for tea
11:33 AM Tom_L: my kid is training on 3d scanners at his work / college
11:33 AM Tom_L: gonna do some reverse engineering
11:33 AM rue_mohr: I wonder what the resolutions are
11:33 AM Tom_L: really good
11:33 AM Tom_L: the cheap ones are ~$250k
11:34 AM Tom_L: they've got several different kinds. some have less res than others but for different purposes
11:35 AM Tom_L: a building doesn't need .0005" res
11:36 AM Tom_L: they get to take apart an airplane and scan it
11:38 AM Tom_L: some are portable for composite wing etc repair
11:38 AM Tom_L: they scan a cutout of the damaged cavity and then they can make a composite plug that exactly fits it
03:38 PM gaze__: 3d scanning still just sucks completely
03:38 PM gaze__: I've played with the artec scanners... I thought it'd be way way easier and better than doing photogrammetry with my old DSLR
03:38 PM gaze__: no
03:39 PM gaze__: you still have to be careful with surface prep
04:20 PM rue_mohr: nothing like scanning a mirror and not getting a scan of a mirror