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[00:05:29] <rue_house> k
[00:05:39] <rue_house> you wanna shoot me an stl?
[01:54:47] <rue_bed> yay, I got a 72Mhz arm to flash an led!
[01:55:09] <Triffid_Hunter> yay!
[02:16:56] <rue_bed> I wonder if I could hook its DMA to the converstion complete flag of a 20msps adc?
[02:18:03] <rue_bed> anyhow
[02:18:03] <Triffid_Hunter> rue_bed: sure, that's what DMA is for
[02:18:23] <rue_bed> I have a digital scope to make sometime
[02:18:48] <rue_bed> the multifinction printers scanners, have a 20msps adc
[02:19:06] <rue_bed> which should do just fine
[02:54:29] <upq> hello
[02:54:45] <upq> I was thinking about building a robot chassis
[02:54:54] <upq> there is something unclear to me about the motors
[02:55:22] <upq> now in order for this whole setup to work what are the parts that I need besides the motors
[02:55:46] <upq> I read about motor drivers and controllers what is the difference and do I need both?
[02:56:26] <upq> my other question is about side movement ? what should I consider for side movement (I dont want to use a 360 ball) I was thinkinkg either tank or 4wd build
[03:00:20] <Triffid_Hunter> upq: for small robots, a skid works fine.. ping pong ball :P
[03:00:52] <Triffid_Hunter> upq: motor driver converts logic signals into high current power for the motor, your controller tells the drivers what you want the motor to do
[03:01:50] <upq> Triffid_Hunter: so I need a motors, motor drivers and a controller for a basic moving chasiss
[03:02:06] <Jak_o_Shadows> Has there ever been a controller that doesn' need the motor driver?
[03:02:10] <Jak_o_Shadows> excluding PLCs I suppose
[03:02:12] <Triffid_Hunter> upq: yep, plenty of kits on sites like sparkfun, adafruit, pololu, etc
[03:02:43] <Triffid_Hunter> upq: some people use continuous rotation servos, which have a motor driver built in
[03:02:44] <upq> Triffid_Hunter im thinking about building everything by my self (thats how I learnt everything I know in life)
[03:03:18] <Triffid_Hunter> upq: well motor driver is simple enough, ask google about h-bridges. note that most of the discrete ones are fairly terrible. use an arduino for your controller
[03:04:21] <upq> that was my other question btw is the controller and driver compatiable with the arduino and raspberry pi
[03:04:30] <Triffid_Hunter> upq:
http://imgur.com/a/IDQ5u is a motor driver I designed a while ago for my RC car
[03:05:01] <Triffid_Hunter> upq: arduino *is* the controller. RPi is an application processor with an OS and thus not particularly suitable for controlling motors, best to use an RPi and an arduino together
[03:06:00] <upq> Triffid_Hunter: thats what I was thinking but I didnt see a much builds using this setup ,
[03:06:19] <Triffid_Hunter> upq: curiously, the motor driver I linked above has an atmega328 on it, same chip as arduinos :P
[03:06:56] <Triffid_Hunter> upq: you should be fine using a motor driver from sparkfun, adafruit, pololu, ebay, aliexpress, etc.. just make sure it's rated for the stall current of your motor
[03:07:09] <upq> it looks compilcated to build
[03:07:53] <Triffid_Hunter> upq: that's just because you're not familiar with all the parts yet, electronics is like lego, except more hierarchical
[03:08:04] <upq> My biggest concern for now is getting all my materials and parts , im leaving the states in 10 days and I wont be able to buy so Im trying to get my bom for now
[03:08:34] <Triffid_Hunter> upq: why are you planning to make a robot just before leaving the country/
[03:09:46] <upq> Triffid_Hunter: no I just want the parts im not gonna build it in 10 days
[03:10:53] <upq> I need to get the parts in 10 days :), Im leaving for 6 months to dubai , and there is no much intrest in robotics there and no aviliable parts, shipping to their also sucks and 99% not avilible
[03:12:49] <upq> Triffid_Hunter: last couple of questions please :)
[03:12:58] <upq> 1. is communicating between arduino and raspberry trivial?
[03:13:28] <upq> 2. can I use a power bank 5v 2.4 a to power the raspberry pi and if so do you recommend it?
[03:17:22] <deshipu> upq: 2.4 what?
[03:17:30] <upq> 2.4a
[03:18:01] <deshipu> should be fine
[03:18:31] <deshipu> and yes, it's as trivial as arduino communicating with your pc
[03:19:35] <Triffid_Hunter> upq: 1) it just plugs in the usb port
[03:20:00] <Triffid_Hunter> upq: 2) should work fine
[03:20:01] <upq> and share the data gathered from arduino sensors to the raspberry pi to process
[03:20:14] <Triffid_Hunter> upq: well that's entirely up to the firmware and software you write
[03:20:15] <upq> software wise it is trivial but Im concered about the hardware ,
[03:20:25] <deshipu> for that you will need to invent and implement some protocol, but sure
[03:20:45] <deshipu> hardware-wise it's trivial, may be some work software-wise
[03:21:02] <Triffid_Hunter> upq: arduino shows up as a usb serial device, just set baudrate and talk to your firmware over serial.. don't send anything in the first couple of seconds after connect though or you'll false-trigger the bootloader
[03:21:04] <deshipu> you just have a stream of bytes
[03:21:45] <upq> great
[03:22:08] <upq> do you power the motors , arduino and raspberry pi each seperately or is there a way to power them all from the same source?
[03:22:36] <upq> I mean what do I need for powering the motors, the controller and the application processor
[03:22:41] <Triffid_Hunter> upq: motor drivers will want a battery
[03:23:01] <Triffid_Hunter> upq: RPi can be powered by anything that puts out 5v at >=2A
[03:23:08] <Triffid_Hunter> upq: eg LM2596
[03:23:52] <Triffid_Hunter> upq: I like 3S lipos from hobbyking for most of my projects, 2.2Ah should be ample, and you can hook your 5v converter to the balance plug.. some soldering required probably
[03:24:18] <upq> Triffid_Hunter: and for the ardunio?
[03:24:24] <Triffid_Hunter> upq: just be aware that their power density is terrifying, you *will* have a fire if you accidentally short anything with one of those connected
[03:24:32] <Triffid_Hunter> upq: it gets power over usb...
[03:24:41] <upq> ooh sorry thats right .. :D
[03:24:45] <Triffid_Hunter> upq: usb supplies both power and data :P
[03:25:04] <upq> I know I know :D I forgot that it would be connected over usb
[03:25:18] <upq> haha , good to feel stupid again
[03:25:52] <upq> if you dont get this feeling from time to time this means you are not learning anything new
[03:25:58] <upq> or you are too smart for that
[03:26:01] <Triffid_Hunter> upq: google knows a zillion tutorials on basic mobile robot platforms btw, spend a couple days doing some reading
[03:26:11] <Triffid_Hunter> upq: agreed! :)
[03:26:31] <upq> Triffid_Hunter: I have been doing that but trust me sometimes asking a human si 102910291 times better
[03:26:33] <Triffid_Hunter> upq: can probably get complete kits including arduino from amazon or wherever you like to shop
[03:27:18] <upq> Triffid_Hunter: I know but I want to get emotionally attached to it to to be able to spend energy and time on it or other wise It wont work for me (personal disorder I guess)
[03:27:34] <upq> thats why im building it my self
[03:27:37] <Triffid_Hunter> upq: ah, you want to put your own egg in the cake, I see
[03:28:22] <upq> Thank you so much Triffid_Hunter You have been a great help, and thanks for deshipu
[03:53:47] <upq> Im just wondering how do tank or 4wd robots turn right and left or rotate
[03:53:53] <upq> do you need a servo for that?
[03:54:20] <owl-v-> servo or dc motor will do
[03:54:28] <Triffid_Hunter> upq: they drive the wheels on each side at different speeds, opposite directions if you want the turning centre within the wheelbase
[03:57:02] <upq> ooh so you can have that with only 4 or 2 motor set up
[03:57:17] <upq> Triffid_Hunter: sofware trick.
[03:57:40] <Triffid_Hunter> upq: trick? no, that's how differential drive works
[03:57:57] <upq> Triffid_Hunter: i didnt even know that
[03:58:12] <Triffid_Hunter> upq: "car" steering is called 'ackerman' for your googling pleasure
[03:58:45] <upq> Im a programmer / artist athelete ,
[03:58:59] <upq> Triffid_Hunter: I have never gotten my hands dirty
[03:59:03] <upq> never ..
[03:59:14] <upq> First timer here ,
[04:03:21] <owl-v-> what do you think of the new microcontroller attiny102/104 ?
[04:03:59] <Triffid_Hunter> owl-v-: arm cortex M-series are so cheap, why bother investing in 8-bit?
[04:07:06] <owl-v-> Triffid_Hunter: which vender's cortex-m do you recommend?
[04:07:30] <owl-v-> I was thinking using avr or pic micro
[04:07:36] <Triffid_Hunter> owl-v-: well I'm familiar with LPC1768 but haven't really checked out the (numerous) other options
[04:08:10] <Triffid_Hunter> owl-v-: pic? nooo, their toolchains are bloody awful due to the core only having one register
[04:12:33] <owl-v-> Triffid_Hunter: 1 register?
[04:14:06] <Triffid_Hunter> owl-v-: yeah, well pic16f and I think pic18f too, not sure about more recent ones.. everyone I talk to avoids them like the plague because the least bad compiler is sdcc and it's still abhorrent compared to gcc. everyone who's tried to port gcc for pic has afaik failed or given up
[04:14:18] <Triffid_Hunter> owl-v-: gcc works fine on avr and ARM however
[04:18:43] <owl-v-> I have used Arduino and pic32MX in the past. I thought attiny102/104 would be a nice addition for future projects.
[04:18:55] <owl-v-> Triffid_Hunter:^
[04:20:58] <owl-v-> but then, pic12 has more peripherals to play with
[04:29:16] <owl-v-> Triffid_Hunter: which micros do you use?
[04:32:49] <Triffid_Hunter> owl-v-: atmega328, atmega2560 and lpc1768
[08:16:07] <upq> do you recommend using the raspberry pi official camera or any web camera will do?
[08:16:18] <upq> as they are a bit expinsive
[08:17:24] <SpeedEvil> The official camera is not connected over USB
[08:17:44] <SpeedEvil> The USB port is already contended, and already shared between network, and all other USB peripherals
[08:30:28] <veverak> also
[08:30:37] <veverak> rpi camera is more space effecient usually :)
[08:46:22] <upq> veverak: no other advantages than space because its not a problem in my case and about usb I can use a usb hub
[08:51:03] <anonnumberanon> oh god the rpi camera was a horror story for me
[08:51:31] <anonnumberanon> it worked well when the ribbon cable didn't damage itself from even barely rough use
[08:52:09] <anonnumberanon> although it may have been one of the teammates sabotaging it because he was evil like that
[08:52:57] <anonnumberanon> he once stabbed a raspi the team was working on when he brought it home and claimed that his dog played with it and they were tooth marks
[08:58:23] <Snert> raspicide?
[09:28:00] <anonnumberanon> armicide :)
[09:29:02] <Snert> No pizza for HIM.
[09:29:26] <veverak> upq: believe me
[09:29:34] <veverak> upq: USB can become quite unfriendly
[09:29:36] <veverak> :)
[09:31:14] <anonnumberanon> are you kidding pizza was the only thing I could offer him to keep working on that damn video live feed!
[09:38:14] <Snert> I am a firm believer in bribery so good goin'.
[09:38:27] <Snert> why, just look at Hillary :)
[11:01:42] <anonnumberanon> holy fuck!
[11:01:43] <anonnumberanon> http://spectrum.ieee.org/tech-talk/semiconductors/optoelectronics/mit-lidar-on-a-chip?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+IeeeSpectrum+%28IEEE+Spectrum%29&utm_content=FaceBook
[11:16:28] <owl-v-> holy moly!
[11:47:07] <z64555> neat
[12:25:44] <Snert_> very kool. "We're only using it in bombs but I'm sure the technology will trickle down in a dacade".