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[00:34:03] <anniepoo> 8cD I'm powder coating
[00:47:30] <mrdata> just a light dusting of icing sugar?
[02:51:04] * anniepoo hands mrdata a donut
[02:52:28] <deshipu> jhylands: are you planning to add a gripper? :P
[02:57:02] <rue_shop3> the going sideways motion is taking up all the energy, there is almost no forwardness going on
[02:57:14] <rue_shop3> castle needs to be smaller
[06:23:05] <Solarlux> Where channel about CNC mahcines?
[06:23:39] <jhylands> deshipu, we are planning on adding a gripper. yes
[06:23:57] <deshipu> woo, underwater rescue
[06:24:06] <deshipu> and/or wreck pilfering
[06:24:41] <jhylands> yeah - bit of a story - my friend was at a provincial park last summer, jumped off a 3 meter cliff into the lake with his gopro on his head
[06:24:51] <jhylands> gopro came off, sank to the bottom, in 10m of water
[06:25:13] <deshipu> and he really wants that footage
[06:25:13] <jhylands> so this ROV (which we've wanted to build for a long time anyways) is SARBot
[06:25:26] <jhylands> no, he doesn't care about that
[06:25:59] <jhylands> the underwater videos of my old AUV were taken with an old ROV that he built, many years ago
[06:26:17] <jhylands> we've wanted to build a newer, more capable one for many years now
[06:26:29] <jhylands> this was just the push he needed to buy the parts
[06:26:35] <deshipu> roger
[06:32:09] <SpeedEvil> There are probably places you could prospect for gopros.
[22:13:28] <kcirick> I want to control two motors that is suggested at 3V... does that mean I need to get a power supply with 6V?
[22:17:55] <z64555> kcirick: Will you be powering the motors in parallel or in series?
[22:18:03] <z64555> *electrically
[22:18:46] <kcirick> z64555: I'm not sure... I'm using this driver:
https://www.sparkfun.com/products/9457
[22:18:55] <kcirick> TB6612FNG
[22:19:52] <z64555> :)
[22:20:13] <kcirick> looks like parallel from schematics, but not sure... do you know anything about it?
[22:20:38] <kcirick> I'm basically trying to figure out of 3.7V LIPO battery is good enough
[22:20:47] <z64555> they're controlled independantly, from the two input signals to it
[22:20:57] <Jak_o_Shadows> I would say your battery is fine. as a guess.
[22:21:13] <z64555> So, you'll need a 3V power supply that can handle the current draw from both
[22:21:30] <z64555> What's its discharge (S) rating
[22:21:37] <z64555> and what is its capacity
[22:22:00] <kcirick> so 3.7V, with high current output, yes? I've been trying several 1.5V alkalines because I have tons of them lying around, but not enough current, I think
[22:22:15] <kcirick> Of the LIPO? I haven't got one yet
[22:23:10] <Jak_o_Shadows> they don't seem like large motors anyway.
[22:23:29] <z64555> yeah, it's only rated for 1.2 amps continous output per motor
[22:24:19] <kcirick> I was looking at this battery:
http://www.canadarobotix.com/battery-chargers/battery-lithium-1000mah
[22:24:45] <Wetmelon> Probably ok, won't last too long
[22:25:10] <Wetmelon> oh, nope. Max discharge current is 1C
[22:25:11] <kcirick> Hm... less than an hour?
[22:25:15] <Wetmelon> It's a little too small
[22:26:38] <kcirick> so I need to look ofr discharge current of more than 1.2A, right?
[22:27:01] <kcirick> z64555: by the way, where did you see that value?
[22:28:32] <kcirick> z64555: 1.2A is the maximum that the motor driver can output per channel
[22:29:24] <kcirick> This is the kit I'm building:
https://www.sparkfun.com/products/12091
[22:29:46] <z64555> "The TB6612FNG motor driver can control up to two DC motors at a constant current of 1.2A (3.2A peak)."
[22:30:07] <kcirick> The datasheet for the gearbox says 170mA max current
[22:30:11] <z64555> 3.2A peak is when the motor is starting up or stalls
[22:30:42] <z64555> doh, they use C, not S for discharge rating
[22:30:52] <z64555> So yeah, that battery won't do it.
[22:31:08] <z64555> C rating, such as 1C, means how much the battery can oomf out current
[22:31:14] <kcirick> z64555: but that's the driver... doesnt it depend on what motor you put on it?
[22:31:52] <z64555> ah, true
[22:32:23] <kcirick> datasheet for the motor (the gearbox):
http://cdn.sparkfun.com/datasheets/Robotics/DG02S.pdf
[22:32:24] <z64555> so you'll be fine in that case, your motors are wimpy compared to the driver
[22:33:00] <kcirick> yes, I'm not building an industrial rover, just a whimpy indoor rover ;-)
[22:33:22] <kcirick> but am I reading that correctly? It draws max of 170mA per motor?
[22:34:53] * z64555 waits on slow internet
[22:35:34] * kcirick waits on z64555's slow internet
[22:35:38] <kcirick> ;-)
[22:35:48] <z64555> yeah, this isn't working out for me today
[22:35:56] * z64555 pokes Jak_o_Shadows
[22:36:24] <z64555> Would you or Wetmelon take a look? thanks
[22:37:27] <Wetmelon> Nope, the no load current is 125 typical, or 170mA max
[22:37:34] <Wetmelon> It doesn't say what the stall current is
[22:38:36] <kcirick> would it be something that the LIPO battery I posted wouldn't work?
[22:39:02] <Wetmelon> That LiPo can output a max of 1 amp
[22:39:30] <Wetmelon> https://www.sparkfun.com/products/13258 assuming this is your motor, if you grab the wheel (stop it from moving), each motor will draw 1.5A
[22:39:58] <Wetmelon> So your battery is only capable of putting out 1/3 of the current needed without catching fire or something
[22:40:46] <kcirick> oh huh...
[22:41:02] <Jak_o_Shadows> hang on.
[22:42:12] <Jak_o_Shadows> That's true.
[22:42:19] <Jak_o_Shadows> But the battery has over-current protection
[22:42:31] <Jak_o_Shadows> so really, you won't make it there in the first place
[22:43:21] <kcirick> but I still need a battery that has max discharge current of 3A
[22:43:51] <Jak_o_Shadows> Well, it would be better. You'd also want to up your motor driver
[22:45:09] <Jak_o_Shadows> if you're not looking at doing it soon, ebay would be cheaper
[22:47:22] <kcirick> Jak_o_Shadows: do you have any suggestions for the driver? I think I did some review and all of them had the same performance
[22:47:59] <Jak_o_Shadows> actually, that driver might be ok
[22:48:05] <Jak_o_Shadows> as long as you don't consistently stall the motors
[22:48:22] <kcirick> Jak_o_Shadows: I plan not to
[22:48:56] <zhanx> Plan to and do are two separate things
[22:49:19] <Jak_o_Shadows> which is pretty much the advice I got here a few years ago :P
[22:49:35] <zhanx> Kcirick, look at r/c car race batteries
[22:49:37] <kcirick> well I'm not sure what I'm going to do until I do it
[22:49:40] <Jak_o_Shadows> Hmm. I'd suggest a L298N thingy (
http://www.ebay.com.au/itm/L298N-Dual-H-Bridge-Stepper-Motor-Driver-Controller-Board-Module-for-Arduino-FB-/172185706853?hash=item2817116165:g:C~MAAOSwYmZXIzLU), but the voltage is higher
[22:50:15] <Jak_o_Shadows> http://www.ebay.com.au/itm/2X-1-5A-2-way-DC-Motor-Driver-Module-PWM-Speed-Dual-H-Bridge-Stepper-L298N-DA-/152098096889?hash=item2369c0c6f9:g:hkoAAOSwwpdW67Pk may also work?
[22:50:24] <Jak_o_Shadows> (I have one of each, but I've never used either)
[22:50:47] <zhanx> http://m.imgur.com/ppRt4l2,FguQjHS,0xhFotK,fta5LiJ,y8ynV9f father day gift from the wife
[22:51:13] <Jak_o_Shadows> A nice monitor stand?
[22:51:14] <Jak_o_Shadows> Sweet
[22:51:18] <zhanx> to make a robotic arm
[22:51:24] <zhanx> 8 dof
[22:51:29] <Jak_o_Shadows> Nice.
[22:51:41] <Jak_o_Shadows> I'm sorta doing the opposite: making a lamp into a monitor stand
[22:52:10] <zhanx> Off an ultrasound machine they tossed out at her work (to bad I didn't get the good parts)
[22:53:12] <kcirick> "The TB6612FNG motor driver can control up to two DC motors at a constant current of 1.2A (3.2A peak)"
[22:53:29] <Jak_o_Shadows> Yeah. But if you stall, you'll be at 1.5A constant
[22:53:36] <kcirick> gotcha
[22:54:36] <kcirick> So I initially tried with several 1.5V AA batteries, and going forward/backward was fine, but couldn't turn/pivot
[22:54:50] <Jak_o_Shadows> Like, in parallel?
[22:54:56] <Jak_o_Shadows> 2x in series, rest in parallel?
[22:54:59] <zhanx> Too much draw
[22:55:40] <kcirick> hmm?? 5 AA connected in series
[22:56:20] <Jak_o_Shadows> series is not what you want for this
[22:56:29] <Jak_o_Shadows> Series adds voltage: parallel adds current capabilitiy
[22:56:55] <zhanx> Needs a parallel series is all
[22:57:30] <kcirick> Jak_o_Shadows: Aha Oho... so if I got two 3.7V LIPO, then I can just connect them in parallel?
[22:57:33] <zhanx> Use 6, 3 in series each side and each set of 3 parallel
[22:58:01] <kcirick> zhanx: interesting
[22:58:36] <Jak_o_Shadows> lii've never used Li-Pos
[22:58:53] <zhanx> That will give you the v and the Amps you need
[22:58:53] <Jak_o_Shadows> they are trickier than AA's in general
[22:59:18] <kcirick> I heard AA's have inconsistent current output... but it doesnt matter for this case?
[22:59:24] <zhanx> I would recommend not running lipo in particular like that
[22:59:31] <kcirick> Alkaline anyway
[22:59:36] <kcirick> zhanx: I've also read that somewhere
[23:00:29] <zhanx> I mean you can but charges and stuff like thst get tricky
[23:00:56] <zhanx> Also discharge rates etc (due to wire length )
[23:01:04] <kcirick> what's the best way to connect AA batteries together? my batter holder connects 5 AA's in series only
[23:01:07] <zhanx> I am not an expert
[23:01:45] <zhanx> Kcirick to test ? Just tape them
[23:01:48] <z64555> kcirck: Use cradels, and do the series/parallel connections from there
[23:02:09] <z64555> most cradels will connect them in series
[23:02:23] <Jak_o_Shadows> ebay. Buy new battery holders
[23:02:42] <z64555> but, if you're lucky and skilled with a soldering iron, you can rewire them to whatever configuration you need
[23:04:03] <kcirick> Probably stick to spending more money :-)
[23:04:35] <z64555> no fun. :P
[23:04:46] <Jak_o_Shadows> If you don't need it urgently, definitely look at ebay and aliexpress
[23:05:07] <kcirick> I should probably know this, but what happens if you connect 2 batteries and 3 batteries in parallel? Would the output voltage be only of the 2 batteries?
[23:05:31] <Jak_o_Shadows> Not quite sure what you mean.
[23:05:49] <Jak_o_Shadows> Generally, when connecting in parallel, connect banks of the same number of batteries
[23:06:00] <Jak_o_Shadows> otherwise it'll try to charge the lesser ones
[23:06:53] <kcirick> Jak_o_Shadows: yeah, but if it's a non-rechargable battery, then it doesn't do that right?
[23:07:06] <Jak_o_Shadows> erm. It won't succeed at doing it
[23:07:18] <Jak_o_Shadows> but it's not a good idea
[23:07:36] <kcirick> Jak_o_Shadows: just trying to think back to my first year physics
[23:07:42] <z64555> kcirick: What will happen is that the voltage will be that of the highest, initially
[23:08:03] <Jak_o_Shadows> What degree are you doing kcirick?
[23:08:07] <z64555> you'll get some current paths in weird ways
[23:08:45] <Jak_o_Shadows> If you don't mind me asking
[23:09:03] <kcirick> Jak_o_Shadows: has doctorate in physics, but has nothing to do with electronics, and has little hardware experience
[23:09:31] <kcirick> trying to learn hardware/robotic for work
[23:09:43] <Jak_o_Shadows> Bloody physicisits :P (I have a relative who is a physicist)
[23:10:14] <Jak_o_Shadows> Theoretical or experimental? Said relative is doing lattice stuff
[23:10:53] <kcirick> I only know my expertise area (+ statistics which I heavily used)... Experimental particle physics
[23:11:58] <z64555> At best, the source with the higher voltage will be drained faster until it stabelizes with the lower voltage sources
[23:12:00] <Jak_o_Shadows> cool
[23:12:25] <z64555> at worst, you'll have a current going through the lower voltage sources... which will heat up the source or worse
[23:13:03] <kcirick> z64555: makes sense... yeah, I won't attempt
[23:13:45] <z64555> this is why some devices warn you to never to mix power cells of different states (empty, sorta empty, etc.)
[23:14:16] <Jak_o_Shadows> Relative says: "Boooo, SUSY"
[23:14:20] <kcirick> which mostly everyone ignores
[23:14:37] <kcirick> Jak_o_Shadows: SUSY was the topic of my PhD thesis
[23:14:51] <z64555> and then they wonder why their radio suddenly burst into flames
[23:15:06] <Jak_o_Shadows> Relative is not a fan. Thinks it's bullshit to add so much stuff :P
[23:16:17] <kcirick> What's his/her take on what's beyond Higgs?
[23:16:31] <kcirick> I think SUSY is dead too
[23:17:23] <Jak_o_Shadows> Hasn't looked into it much, but is a fan of composite higgs. Relative agrees about SUSY :P
[23:18:29] <kcirick> Jak_o_Shadows: You know, there is a dark photon lurking about at CERN, could be interesting
[23:19:34] <Jak_o_Shadows> diphoton excess?
[23:21:07] <kcirick> diphoton excess is for Higgs (still within the standard model)... dark photon is something beyond the standard model
[23:21:51] <Jak_o_Shadows> I believe this may be getting beyond their expertise. They work within the standard model
[23:22:42] <kcirick> Jak_o_Shadows: hence they don't give rats behind about SUSY :-) also has nothing to do with robotics, I'm sure
[23:22:42] <zhanx> Beyond expertise, heck I am diesel mechanic
[23:22:53] <Jak_o_Shadows> haha
[23:22:55] <zhanx> I said ok
[23:23:10] <kcirick> I would love to be able to work on my car
[23:23:21] <zhanx> I could make your car
[23:23:33] <zhanx> But your job nope
[23:25:58] <zhanx> But, this fall should be the start of my third year of college (only taken 7 years )
[23:26:01] <kcirick> well, I really appreciated your help with my battery question.. I think I know what to do next
[23:26:19] <zhanx> Test, break, repeat
[23:26:51] <Jak_o_Shadows> mech eng zhanx?
[23:27:08] <kcirick> I just don't want the process to be Test, Burn/Explode, End
[23:27:10] <zhanx> Robotics engineering, was mech
[23:27:27] <Jak_o_Shadows> coolo
[23:27:51] <zhanx> Kcirick use caution is all, triple check
[23:28:15] <Jak_o_Shadows> Don't hesitate to ask.
[23:28:18] <zhanx> After that before you power it on take a break, review your notes and check again
[23:28:22] <Jak_o_Shadows> Rue is your time zone as well, which is nice
[23:28:36] <zhanx> Rue is Mia tonight
[23:29:12] <zhanx> I sent him the link of the arm I got to make as a helper and zero
[23:29:52] <kcirick> I like how responsive you guys are (and helpful). other channels I visit are too quiet and no response when I ask questions
[23:30:28] <zhanx> Kcirick, like jak try when we can
[23:31:00] <zhanx> Even though I am diesel mechanic, doesn't mean I have built a few robots
[23:31:09] <zhanx> Err haven't
[23:31:44] <Jak_o_Shadows> just because I haven't doesn't mean you can shut me up :P
[23:32:06] <zhanx> :p I am just better at the fab part is all jak
[23:32:35] <kcirick> Ok. I'm off to bed... I'm sure I'll be back soon for more questions
[23:32:41] <Jak_o_Shadows> haha. definitely
[23:32:54] <kcirick> cheerio
[23:33:08] <z64555> hm.
[23:33:25] <z64555> zhanx: have you ever made a gimbal?
[23:33:32] <z64555> or set of gimbals
[23:33:36] <zhanx> One
[23:33:50] <z64555> how many axes?
[23:33:53] <zhanx> It was a 2 axis
[23:34:18] <z64555> ah, so a wishbone with a z-axis bearing?
[23:34:31] <zhanx> Yep
[23:34:33] * z64555 gets all the lingo wrong
[23:34:47] <zhanx> I get what you mean
[23:35:16] <z64555> ok. Yeah, that's what I was thinking for a 2-axis gimbal, eventually I'll need to make a 3 or possibly a 4 axis
[23:35:41] <zhanx> Each axis gets harder to add (but plan for the end goal)
[23:36:53] <z64555> I'm unsure of what material I'll need to use, My quad is about 1Kg but I'd like to be prepared for 2Kg or more
[23:37:21] <zhanx> Well to start balsa wood is cheap
[23:37:34] <zhanx> Makes prototypes easy
[23:37:40] <zhanx> Or straws
[23:38:17] <zhanx> Pvc pipe is good also
[23:38:50] <zhanx> A 3" coupling fit my camera awesome
[23:40:02] <zhanx> http://makezine.com/2009/07/16/how-to-pvc-gimbal-stabilizer/
[23:40:20] <zhanx> Basically what I did
[23:51:45] <z64555> eh, my quad is much bigger than any PVC pipe :D
[23:52:06] <z64555> its about 2 feet in diameter
[23:53:26] <zhanx> Fyi sewer pip is pvc and goes a bit bigger
[23:54:25] <z64555> the largest I've seen at the hardware store is 4 inches
[23:55:26] <zhanx> Your better off bending acrylic for the weight