#avr Logs

May 18 2021

09:18 AM Arch-TK is now known as atk
09:28 AM rue_mohr: anyone ever done a loopback test on a jtag interface?
04:44 PM SamantazFox_ is now known as SamantazFox
05:33 PM vmt: has anyone done stuff with strain gauges here?
05:47 PM cehteh: i got some accidentally delivered from china, where excess in some package .. and put them into my shelf. does that count? :)
05:49 PM vmt: heh
05:49 PM vmt: well, unfortunately not i believe
05:50 PM vmt: i'm just thinking about those printed ones you can glue on. i'm trying to figure out how sensitive they are to perpendicular force
05:51 PM vmt: as they're really for measuring strain on the plane
05:52 PM cehteh: i guess datasheets should exist
05:53 PM cehteh: and mechanically possibly any prependicular force translates into a counterforce at 90°
05:54 PM vmt: well, depends on the glue, and the actual traces, substrate
05:54 PM cehteh: means dunno if that cancels out or one or the other component is more, possiby you should avoid that or you run into calibration problems
05:54 PM vmt: i guess to answer my question i should just order some and test, there's no other way around this as this is how these things aren't meant to be used
05:55 PM cehteh: do you have testing equipment for that .. i mean the real laboratory stuff?
05:55 PM cehteh: guess not
05:55 PM cehteh: would it matter much?
05:56 PM vmt: i do have proper test gear, but no strain gauges :D
05:56 PM cehteh: can you add 2 string gauges at some angle?
05:56 PM vmt: i've been thinking about different configurations for this, and i may end up doing something like that
05:56 PM cehteh: and then do some math to get the directional vector you want
05:57 PM cehteh: dunno how precise/important your measuments are, but i think i had a better feeling with that if side forces cant prevented
05:58 PM cehteh: all i knon is that strain gauges are bitches .. about glue, calibration, materials and all
05:58 PM vmt: cehteh: yeah, of course. it's just that it complicates construction, though 3d printers exist...
06:00 PM cehteh: about glue: for constructive stuff i have much better results with PMMA glue than epoxy ... if the strain gauges you want to use allow that i recommend that. google for weicon rk-1500 ot competing products
06:01 PM cehteh: pretty expensive shit but insanely stong adhersion
06:02 PM vmt: i'll keep that in mind, thanks. i might actually screw strain gauges altogether, but i'll order some and do some testing
06:03 PM cehteh: yes depends what kinds you have .. some come as film strips to be glued on as user, some come monted on some aluminium or something else profiles for screwing
06:05 PM cehteh: https://commons.wikimedia.org/wiki/Category:Strain_gauges?uselang=de looking at the 'rosette' types .. i guess there is some need for multiaxial stuff/calibration/correction
06:09 PM vmt: mmmm
06:10 PM cehteh: when you goofle you find free books
06:10 PM cehteh: google
07:23 PM specing_ is now known as specing