#robotics Logs

May 24 2017

12:00 AM anniepoo: were you imagining it'd be something else?
12:10 AM rue_house: anniepoo, wait, you do stm32?
12:13 AM anniepoo: a little
12:13 AM anniepoo: not much
12:13 AM anniepoo: I'm a noob at stm32
12:13 AM rue_house: so ou cant tell me why my light dosnt' flash?
12:16 AM anniepoo: probably not
12:16 AM rue_house: I'm stupposed to flash the elf, right?
12:16 AM rue_house: ^ ^
12:16 AM rue_house: o o
12:16 AM anniepoo: I am about at that point
12:16 AM anniepoo: I discovered the LED I was using took more current than the stm32 could supply
12:16 AM anniepoo: adding a transistor fixed it
12:16 AM anniepoo: disconnect LED and stick a scope on it
12:16 AM anniepoo: maybe you have same problem
12:16 AM rue_house: I know it can drive this one
12:16 AM rue_house: its an onboard thats flashed before
12:16 AM anniepoo: ok, timer issue?
12:16 AM anniepoo: are you using an ST-Link?
12:17 AM rue_house: yes
12:22 AM anniepoo: do you have GDB working?
12:22 AM anniepoo: can you trace code?
01:00 AM rue_house: well there was a power blink, so untill I get the main stuff back online, there isn't much of anything
01:00 AM rue_house: :/
01:00 AM anniepoo: 8c/
01:01 AM rue_house: this is where I remember that switching the house lighting over to 12V would be a good idea
01:07 AM rue_house: hmm
01:08 AM rue_house: from china: 2.40cad ea from digikey, same p/n 21.09cad ea
01:09 AM rue_house: so should I buy another 10?
01:10 AM rue_house: they say its a chineese copy tho
01:10 AM anniepoo: of what?
01:10 AM rue_house: https://www.aliexpress.com/item/3590S-2-103L-3590S-2-10K-OHM-2W-10-Turn-Wirewound-Potentiometer-x-10PCS/1970430793.html
01:10 AM rue_house: the box says made in mexico
01:11 AM anniepoo: pots are probably pots
01:11 AM anniepoo: 8cD I'd do China
01:11 AM rue_house: yea
01:13 AM rue_house: I'll check them out a bit tommorow
01:13 AM rue_house: http://www.bourns.com/docs/Product-Datasheets/3590.pdf
01:20 AM anniepoo: off to check the shell
01:21 AM rue_house: hope you have more luck than me, my fiberglass was stickey for about 6 months
01:23 AM mrdata_: not well mixed? not perfect proportion of resin to hardener?
01:23 AM rue_house: chemicals sitting on a shelf for years before being used?
01:23 AM rue_house: pff me? no
01:26 AM mrdata_: happens all the time
01:30 AM anniepoo: I had one batch that was sticky
01:31 AM anniepoo: I cured the spots by painting them with straight hardener and small brush
01:56 AM juanonymous: can someone here point me to a site to start my own basic robot?
01:56 AM juanonymous: not the complex one
01:56 AM juanonymous: thanks
01:59 AM rue_house: what do you conider basic
01:59 AM rue_house: ?
02:02 AM juanonymous: a basic robot, that can run. or anything for starters like me
02:03 AM orlock: juanonymous: i think one of the top robotics reserch companies made a running robot
02:03 AM orlock: juanonymous: you maybe start with something that has wheels that turn, then get it to not hit a wall
02:03 AM orlock: or at least back up when it hits a wall
02:05 AM juanonymous: sure
02:05 AM juanonymous: can you point me on a site or a community that will guide me on building one?
02:05 AM juanonymous: thanks
02:06 AM orlock: http://letsmakerobots.com/ used to be good
02:06 AM orlock: Unsure now, i dont have the time for them i used to
02:06 AM orlock: Kids, and my employer makes robots
02:07 AM juanonymous: yeah, that is why i am interested to build one. because kids this days, make one.
02:08 AM orlock: Oh, yeah heh i meant
02:08 AM orlock: kids take all my time
02:08 AM juanonymous: oh
02:08 AM juanonymous: ok
02:08 AM juanonymous: lol
02:09 AM orlock: and its a little less interesting/fun when you see everything that goes into making "professional" robots
02:09 AM rue_bed: juanonymous, can you work with a $40 budget and 8 months?
02:09 AM rue_bed: or do you need cheaper and faster
02:12 AM juanonymous: rue_bed, what do you suggest?
02:13 AM juanonymous: i'd like to try the cheaper and faster, first i think
02:19 AM rue_bed: do you make anything now?
02:21 AM juanonymous: rue_bed, not yet
02:21 AM juanonymous: but i wanted to make one
02:24 AM orlock: got a soldering iron and multimeter?
02:28 AM juanonymous: yup
02:28 AM juanonymous: but doesn't know how to use them yet :D
02:29 AM orlock: oh, and some solder
08:36 AM z64555: get you a big breadboard, don't bother the small ones unless you like throwing money at the manufactorer
08:36 AM z64555: juanonymous:
08:37 AM juanonymous: z64555, here
08:37 AM juanonymous: checking stuff online
08:37 AM juanonymous: stuff/s
08:38 AM z64555: The initial cost will probably seem high, but with a large breadboard you can prototype several circuits and even get them to connect to each other
08:40 AM z64555: I picked one up from somebody's kid when they graduated college or switched majors. It's got 3 units of 63 rows, 10 columns, and has 5 voltage rails
08:40 AM z64555: and 4 lugs at the top for 3 voltage sources and a ground
08:41 AM z64555: oh, that's something else you'll need, a power supply that'll plug into the board
08:41 AM z64555: You'll need one that can supply 5V and 3.3V
08:42 AM z64555: You can try building one yourself, too
08:42 AM juanonymous: if building one is cheaper, then ill do that
08:53 AM z64555: well, you can always just use batteries
08:54 AM z64555: A popular source for hacked power supplies is to use one from a PC that got discarded
08:54 AM z64555: it supplies 3.3v, 5v, and 12v
08:54 AM z64555: there's several articles/blogs online that show you how
08:54 AM juanonymous: noted z64555
08:54 AM juanonymous: thanks
08:56 AM z64555: you're welcome. Anything to help a future roboticist. :D
09:03 AM juanonymous: thanks z64555, i love that word "future roboticist" :D
10:04 AM rue_house: like anyone ever put more than one independant circuit on a breadboard at a time
11:23 AM mrdata__: yes
11:42 AM Tom_itx is now known as Tom_L
12:14 PM synja: z64555, i prefer those dc modulators based on pots
12:15 PM synja: wastes more electricity, but good for prototyping
02:59 PM anniepoo: powder coating.
02:59 PM anniepoo: 8cP
03:01 PM Tom_L: kitchen oven?
03:02 PM Tom_L: don't you have to charge that to get it to stick?
03:16 PM mrdata__ is now known as mrdata
03:31 PM slidercrank is now known as Guest70698
04:19 PM anniepoo: Yes, we have a powder coating gun and an oven
04:19 PM anniepoo: 8cD we're well equipped
06:29 PM Elleo_ is now known as Elleo
08:51 PM z64555: synja: voltage dividers, I think they're called. Yeah, I like them for super-simple stuff that won't be powered on for very long, but if I need it for something that
08:52 PM z64555: has a decent on-time I'd want a proper power supply
08:53 PM mrdata: it all depends
08:53 PM mrdata: a voltage divider running at pico-amp currents is a voltage sense
08:54 PM mrdata: and will not drain much power
08:56 PM z64555: Next question would be how much voltage is getting that pico-amp current
08:56 PM z64555: :)
08:56 PM robopal: get an adjustable voltage regulator and you are set
08:57 PM robopal: whatever was the question* :p
08:57 PM z64555: that's not that much better than a voltage divider for a power supply :P
08:58 PM synja: actually i meant a buckup and stepdown circuit
08:58 PM robopal: what happens to a voltage dividers voltage when Vss drops as battery voltage goes down
08:59 PM synja: it will go down as well
08:59 PM synja: the output voltage, that is
08:59 PM robopal: thats why a regulator is better ;-)
08:59 PM z64555: I didn't say it was worse :P
08:59 PM synja: well, it wouldn't be much of a difference robopal
08:59 PM robopal: well it all depends on what you are powering anyway
09:00 PM synja: mm
10:21 PM rue_shop3: nothing like a power outage to clean up programs on the computer
10:21 PM zhanx: https://www.amazon.com/gp/product/B014ECTCB2/ rue_shop3 thoughts on that
10:22 PM rue_shop3: it beats making one from microwave transformers!
10:23 PM anonnumberanon: zhanx, what will you be welding?
10:23 PM anonnumberanon: thickness i mean
10:24 PM zhanx: nothing more than 1/4"
10:24 PM rue_shop3: yea, I had 1/4 - 1/2 as my anticipated max
10:25 PM zhanx: i don't see me doing 1/2" and if i need to my work has the welders for that
10:25 PM zhanx: i can pay the 20 bucks to use it there
10:26 PM anonnumberanon: i had not realized it also had plasma cutter, tig and stick
10:26 PM zhanx: i want it for the stick and plasma, never tig'd
10:52 PM Tom_L: i'd like to try tig but likely never will