#robotics Logs

Jan 06 2015

#robotics Calendar


00:06 rue_house ....
00:06 rue_house in this library
00:06 Jak_o_Shadows wait, arduino libraries are bad?
00:06 Jak_o_Shadows The shock
00:06 rue_house this isn't bad
00:06 rue_house this isn't awefull
00:06 rue_house its not terrible
00:07 rue_house its hardly even up to catastrophic
00:07 rue_house its worse
00:07 rue_house pandemic?
00:07 rue_house ... it could be...
00:08 rue_house were talking about a library where audio samples were clipped to make them 8 bits
00:08 rue_house where they were further clipped for volume control
00:09 rue_house where, it chooses one of 4 sample rates depending on the sample rate in the file, none of which are the files sample rates
00:09 rue_house were talking about throwing out the last not-quite-buffers-worth of data
00:09 rue_house were talking about playing 2 bufferes of garbage at the start of the file
00:10 rue_house were talking about TMRpcm arduino library
00:10 rue_house this dosn't play a file, this makes noise with random data taken from the file
00:33 Hyratel C99: how do I safely cast a int16 to a uint32, right aligned?
00:44 wolfmanjm no such thing as a safe cast in c ;) c++ is a different matter
00:53 Hyratel funny
00:53 Hyratel but how do i do it
00:54 Hyratel wolfmanjm,
00:55 wolfmanjm in c you simply cast... int16 a; uint32 b; b= (uint32)a;
00:55 wolfmanjm actually you don;t even need to cast AFAIK
00:55 wolfmanjm b= a; should work just as well
00:55 Hyratel I've got an 8 bit ADC value
00:56 wolfmanjm and by right aligned I presume you mean lsb0 goes to lsb0
00:56 Hyratel int16
00:56 Hyratel yes
00:56 Hyratel I need to take an 8 sigbit int16 and pass it to an 8 sigbit uint32
00:57 wolfmanjm ok so how about b= a&0xFF;
00:57 Hyratel peel that apart?
00:58 wolfmanjm if you get a warning then b= (uint32)a&0xFF; but I suspect there is no warning in C00
00:58 wolfmanjm C99
00:59 wolfmanjm basically you are doing an arithmetic and operation of the int16 with 0xFF, then assigning it to your uint32. the and will strip off the lower 8bits of the int16
00:59 Hyratel no, I need to pad the left side of the int16 with 16b
01:01 wolfmanjm ? you need this? 0b11111111xxxxxxxx
01:02 wolfmanjm where xxx is the 8 valid bits?
01:02 Hyratel I /have/ that
01:02 wolfmanjm or do you want them to be 0b00000000xxxxxxxx
01:03 Hyratel I need 16 bits of zero padding to the left
01:03 wolfmanjm b= ((uint32)a)&0xFF;
01:03 wolfmanjm where b is a uint32
01:03 wolfmanjm and a is your int16
01:04 wolfmanjm any lathe users/experts around/awake?
01:15 mrdata i'm not an expert, but am awake
01:15 mrdata what'st he trouble, wolfmanjm ?
01:16 wolfmanjm just wondering... i am playing with a new 4 jaw chuck, and was wondering what a decent tolerance is for centering? is 1 thou good enough?
01:17 wolfmanjm my dial guage is good to 1 thou so getting any better means buying a new one :)
01:20 mrdata it's up to you
01:20 mrdata i have dreams of much sharper tolerances
01:21 mrdata but if your gauge is the limit, then go with that
01:22 wolfmanjm well the other question is can you get a better tolerance? seems at 1 thou just touching anyhting deflects the needle at least 0.5thou
01:22 wolfmanjm I may get a 0.5 though guage anyway
01:23 mrdata a russian machinist i spoke to last week, told me that for the work he did, (which was making parts for weapons, back in the day), his tolerance was .01 micrometre
01:24 mrdata whicdh comes out to 0.00039 thousanths of an inch
01:25 wolfmanjm yea that seems excessive :)
01:28 mrdata and dealing with the fact that just touching it moves it 0.5 thou is a matter of knowing a good set of tool tips for your equipment
01:29 mrdata you should know how much the tool rides up, or digs in, and account for that
01:31 mrdata etc
01:31 mrdata but i'm not the expert
01:31 mrdata yet, it doesnt seem like it is much of an improvement to go from 1 thou tolerance to 0.5; i would hope for a 10 to 20 fold improvement
01:32 mrdata but again, what do i know
01:32 wolfmanjm yea indicators that accurate are very very expensive :)
01:32 wolfmanjm well beyond my hobby income
01:32 mrdata i have an insane tolerance ahead of me for a project
01:33 mrdata 9 nm roughness and accuracy
01:34 mrdata i'm kinda thinking it isnt acheivable in a DIY shop
01:39 wolfmanjm yea I certainly couldn;t get that close, 1thou is about my limit
01:40 wolfmanjm had fun trying to make a solid coupler for 1/4" axle and 5mm stepper shaft
01:40 wolfmanjm getting the holes concentric was challenging. ended up the best I could do was about 5thou runout
01:41 wolfmanjm ended up buying some from ebay. and they turned out to not be much better :)
01:42 mrdata tool tips can help; but, yeah
01:43 rue_house open source is like having a project with 2 people who know what their doing and 20000 monkeys who also modify the source... or so I'm getting the feeling
01:45 wolfmanjm rue_house: yea you need a gatekeeper on the repo
01:45 wolfmanjm I'm the smoothie gatekeeper, lots of peopl ehate me, but I don;t let crap in ;)
01:46 rue_house and I see there are wide grey lines,
01:46 rue_house people want a specific feature, but all the patch submissions for it are ... junk
01:46 Jak_o_Shadows what project is this rue?
01:46 rue_house I'm .... rewriting the TMRpcm arduino library
01:47 rue_house it looks like a long time ago, someone knew what they were doing
01:47 rue_house somewhere under here
01:53 rue_house wolfmanjm, does the smoothie work with grbl?
01:53 rue_house I havn't checked it out, I'm assumeing grbl isn't junk
01:54 wolfmanjm smoothie is instead of grbl runs on an arm based MCU
01:54 rue_house oooh
01:54 wolfmanjm grbl is ok
01:54 rue_house I thought it was a "custom arduino"
01:54 wolfmanjm for CNC on an arduino it is pretty good
01:55 wolfmanjm smoothie does 3d printers and CNC,
01:55 rue_house isn't smoothie reprap control?
01:55 wolfmanjm yea
01:55 rue_house ah
01:55 wolfmanjm reprap controller
01:55 wolfmanjm but runs on arm instead of arduino
01:55 rue_house whats better about arm
01:55 wolfmanjm faster
01:55 wolfmanjm 16Mhz vs 120Mhz
01:55 rue_house arduino can already run a reprap faster than the plastic can cool
01:56 wolfmanjm more memory so bigger lookahed queue
01:56 wolfmanjm smoother movements
01:56 rue_house does arduino based stuff have ... velocity anaomolies between strokes?
01:56 wolfmanjm delta printers have a bit of a problem with arduino based controllers, they tend to run out of power
01:57 wolfmanjm yea all the controllers do
01:57 rue_house tahts a bunch of extra math, I could see that
01:57 wolfmanjm there are various techniques to handle movement through junctions linuxcnc probably has the best algorithms for that
01:57 rue_house I been wondering if the finish stroke velocity is the same as the start of the next stroke
01:58 rue_house I'm sure they dont stop after every command
01:58 wolfmanjm well it depends on accelration and jerk settings
01:58 wolfmanjm smoothie uses junction deviation, so it calculates the exit speed based on the angle of the junction
01:58 wolfmanjm the sharper the angle the slower it decelerates to
01:59 wolfmanjm 180° junctions it will decelerate to almost 0
01:59 wolfmanjm but it depends on the accleration setting and the junction deviation
01:59 rue_house I imagine you almost always limited by acceperation, not too many linear stretches I'v seen are long enough to hit max velocity
01:59 rue_house less extruder velocity, wich whould otherwise be the limit
02:00 wolfmanjm well most 3d printers run at 2000-4000 mm/sec²
02:00 wolfmanjm so they can hit max velocity in 2mm or so
02:00 rue_house if I run mine over about 650 it starts screwing up
02:01 rue_house but I can go to 8000mm/s velocity easy
03:27 Veverak well
03:27 Veverak wolfmanjm: that point about smoothies makes one want it
03:29 Veverak like many things
03:29 Veverak buuuuut, I have pretty well working ele. so :/
04:06 deshipu so, I have this idea for a simple positioning system
04:06 deshipu maybe you can point the obvious flaws in it
04:07 deshipu because I'm surprised nobody tried that yet
04:08 deshipu The idea is to have some simple beacons around the room. Each of them is an IR receiver and ultrasound emitter. They are very simpe, basically just send an ultrasound click every time they receive a particular IR signal for that particular beacon.
04:09 deshipu The robot has an IR emitter and ultrasound sensor. It sends IR signals to all the beacons in order, and measures distance by checking the delay.
04:10 deshipu Then it simply trilaterates its position from the known positions of the beacons and the distances.
04:10 deshipu What do you think?
04:19 LiohAu anybody knows if anybody can make its own mecanum wheels or if patents are still active?
04:35 wolfmanjm deshipu: sounds like something I did sometime ago, just used the sonar though. also the IR positioning was used by the Rovio and worked quite well
04:36 wolfmanjm when I say some time ago it was probably 40 years ago when I was doing robotics at Uni
04:37 wolfmanjm placed a few sonar pingers in the corners of the room and got a posiiotn by timing them.
04:37 wolfmanjm I like the IR addition though it saves synchronizong the pulses
04:44 deshipu wolfmanjm: the problem I had with just IR is that it requires directional sensors
04:45 deshipu and I want something small on the robot
04:45 deshipu one thing I'm concerned about is that the ultrasound emitters/receivers are usually directional
04:48 Triffid_Hunter deshipu: use a mirrored cone to turn a directional sensor into a disc-shaped receive pattern.. can even point a camera at it to get a 360° panorama in each frame
04:48 Triffid_Hunter LiohAu: I'm sure they wouldn't bother trying to stop you printing some ;)
04:50 LiohAu but can we sell a robot with mecanum wheels without paying royalties ?
04:51 Triffid_Hunter no idea
04:52 Tom_itx LiohAu, just change up a couple things and make your own
05:28 anonnumberanon T-12 minutes SpaceX launch https://www.youtube.com/watch?v=Ohnnl4nOcGU
05:32 deshipu Triffid_Hunter: not sure how well a mirror will work with ultrasound...
05:33 deshipu anonnumberanon: oh no, it's smoking, that can't be good!
05:33 anonnumberanon haha
05:33 anonnumberanon that is not smoke that is vapor
05:36 Triffid_Hunter deshipu: for IR not ultrasound
05:39 deshipu Triffid_Hunter: I'm not worried about IR so much, it reflects off the ceiling anyways
05:40 deshipu anonnumberanon: toldya something's wrong
05:40 deshipu anonnumberanon: hold hold hold
05:49 orlock Triffid_Hunter: heya
05:49 orlock Triffid_Hunter: ordered an v6 alu hotend (and some threaded rod to replace the bent bits from crappy couplers)
05:50 anonnumberanon so mad
05:50 orlock Triffid_Hunter: and http://dark.crypt.net.au/Prusai3/20150104_200924.jpg
05:50 orlock check out the optical Z endstop holder :)
05:51 Triffid_Hunter orlock: looks like you made it with PCL by hand
05:51 orlock yup!
05:52 orlock it was that, or spend a long time dicking with a cad tool
05:52 orlock works infinitly better than the previousattempts
05:53 orlock lucky the motor mount had an unused through hole in the right spot
05:53 orlock Then, after testing it a bit, i went to start a print
05:54 orlock forgot i had removed the homing routine from the start of the gcode
05:54 orlock it tried to print over the clips holding the glass sheet in place, snapped hot end off at the spot it had been broken before
05:54 orlock it survuved being dragged along and rammed into the glass sheet fine, bit hitting the clip was too much
06:21 DagoRed http://i.imgur.com/KMM8q.jpg
06:21 DagoRed orlock: ^
06:22 orlock hahah saw that :)
06:33 DagoRed Awesome
06:34 DagoRed .HaD 3
06:34 makepi DagoRed: 0.) 3D Printing Circuits Gets Rid of the Box Altogether - http://goo.gl/k40RWk
06:34 makepi DagoRed: 1.) Dedicated Automobile Traffic Monitor with Raspberry Pi - http://goo.gl/yowy25
06:34 makepi DagoRed: 2.) RGB LED Matrices With The STM32 and DMA - http://goo.gl/VRhy9b
06:34 DagoRed 0 and 2 are pretty sweet!
06:36 orlock simplyshipley: HI there
06:40 deshipu hmm... seems like I have some nasty noise on the serial line here: https://www.youtube.com/watch?v=XHKIPd-WXu0
07:20 dmiles_afk has anyone an optimion about Knowrob or tried it?
07:30 deshipu never tried anything with ROS
07:43 DagoRed .weather
07:43 makepi DagoRed: Bethlehem, PA: Light Snow, 15.6 F (-9.1 C), 30.34(-), Feels Like: 16 F (-9 C), Humidity 85%, Wind From the SW at 1.6 MPH Gusting to 3.1 MPH - Last Updated on January 6, 8:23 AM EST http://goo.gl/bAOEM
07:47 deshipu if it knows where you are, it should give you time in your timezone :/
07:58 DagoRed deshipu: try it for your region.
07:58 DagoRed also, feel free to use the .t function
07:58 DagoRed .t PST
07:58 makepi Tue, 06 Jan 2015 05:39:17 PST
07:58 DagoRed So rue is still in bed.
08:01 deshipu .weather
08:01 makepi deshipu: Bethlehem, PA: Light Snow, 15.8 F (-9.0 C), 30.34(-), Feels Like: 16 F (-9 C), Humidity 85%, Wind From the SW at 1.6 MPH Gusting to 2.2 MPH, Precip Today 0.00(in) - Last Updated on January 6, 8:37 AM EST http://goo.gl/bAOEM
08:01 deshipu ah, it doesn't know where you are
08:01 DagoRed no
08:01 deshipu I thought it would use ip location
08:01 DagoRed Why would it do that? Most people use a mask...
08:02 deshipu I didn't thought it out throughoughtly :)
08:08 DagoRed think = thought
08:20 deshipu I haven't thought it out throughoughtly
08:21 DagoRed :)
08:47 ShH stabs deshipu's keyb
08:47 theBear rue_shop4, i'll tell you what tiiime it is !
08:47 theBear i knowrob... i used towork withhim
08:48 theBear and ROS is from frasier... i would try something, but i never met her
09:04 DagoRed hey theBear
09:04 theBear ho dago
09:04 DagoRed How's it goin?
09:06 DagoRed .weather 18018
09:06 makepi DagoRed: Bethlehem, PA: Light Snow, 17.6 F (-8.0 C), 30.30(-), Feels Like: 18 F (-8 C), Humidity 83%, Wind From the SE at 2.2 MPH Gusting to 3.1 MPH, Precip Today 0.00(in) - Last Updated on January 6, 9:45 AM EST http://goo.gl/bAOEM
10:24 codepython777 Hyratel: https://www.sparkfun.com/products/13141 - how resilient are these motors with water on the ground? Or if it starts raining?
10:25 Hyratel uh
10:25 DagoRed .info
10:25 makepi DagoRed: Actobotics Kit - Nomad 4WD Off-Road Chassis - ROB-13141 - SparkFun Electronics- http://goo.gl/LL1oUN
10:25 Hyratel I couldn't tell you. never used em
10:27 codepython777 Hyratel: the motors there are servos, right?
10:27 Hyratel no
10:27 Hyratel those are straight gearmotors
10:28 codepython777 Hyratel: they are 0.5A motors, right? https://www.pololu.com/category/10/brushed-dc-motor-controllers - these look like they are made for much higher rated motors?
10:30 Hyratel https://www.servocity.com/html/195_rpm_precision_planetary_ge.html
10:30 Hyratel this type
10:30 Hyratel though slightly different ratio
10:31 Hyratel if you poke a hole in the rubber boot that's on the backs of the motors and run your wires through that, you should be ok against splashes and rain
10:32 codepython777 Hyratel: Which usb motor controller do you recommend for this particular 4wd?
10:33 Hyratel codepython777, see if you can find a servo library for your raspi GPIO
10:34 Hyratel http://razzpisampler.oreilly.com/ch05.html
11:58 Hyratel so C99 doens't like it when you try to cat strings with (str)foo + (char)bar ... what's a concise alternative?
12:04 armyofevilrobots strncat to prevent overflows
12:05 armyofevilrobots http://en.cppreference.com/w/c/string/byte/strncat
12:36 blib does anyone know of a cheap timer that keeps nanosecond accuate time?
12:43 Mister anyone know where one could get a potentiometer like the one in this video? if you look at 6:19 time
12:44 Mister http://www.youtube.com/watch?v=HN1xSIgnwDA
12:44 Mister is that a potentiometer by the way?
13:33 deshipu Mister: it is, but they are expensive
13:33 deshipu Mister: you can get them in an electronics store
13:33 deshipu Mister: but I suppose you could use an ecoder instead
13:35 Tom_itx that looks like an encoder
13:36 blib is there a good code somewhere for robot navigation (when the map is available)?
13:37 Tom_itx nearly like the encoder i put on my spindle: http://tom-itx.no-ip.biz:81/~webpage/cnc/new_pulleys/spindle_enc2.jpg
13:38 Tom_itx blib, if you had good navigation code you wouldn't need the map
13:41 Mister aha cool
13:41 Mister does encoders need to be syncronized when it starts up?
13:42 Tom_itx not really
13:42 Mister max and minimum
13:42 Tom_itx not for what i'm doing
13:42 Tom_itx it's 3 channel
13:42 Tom_itx A B & X where X is an index
13:43 Mister k, you only synchronize it once?
13:43 Tom_itx never
13:43 Tom_itx at least not yet
13:43 deshipu Tom_itx: there are those high-precision potentiometers with a spiral inside
13:43 deshipu Tom_itx: I have one
13:44 Tom_itx not until the spindle has reverse and i'm able to rigid tap with it will it be a concern
13:44 Tom_itx deshipu, like 20 turn?
13:44 Tom_itx i've got some of those too
13:44 Tom_itx i don't think that's what's in the video
13:44 Mister hmm
13:45 Mister so the encoder is used as a speedometer and buttons for max and minimum?
13:46 Tom_itx you can measure time and distance with it
13:46 Tom_itx and determine forward and reverse
13:47 deshipu Tom_itx: the guy says "ten turn potentiometer"
13:47 Mister k, was thinking of how to stop it
13:47 Mister so it won't break x-D
13:47 Mister when it hits the end
13:47 Tom_itx i wouldn't do it that way personally
13:49 Mister hmm i'm wondering what kind of method to use, ic an think of 2 atm.. one were you have max and minumum Ohm, and one that count rotations
13:49 Mister i can*
13:50 Mister max and minimum ohm can only meassure 1 rotation so i was wondering is it would be ahrd to make a potentiometer yourself?
13:51 Mister using a wire instead of a circular resistance
14:51 Mister detalis on this motor says 400-122rpm, does that meen it cannot go slower then 400rpm?
14:51 Mister http://www.ebay.com/itm/9-300W-brushless-gearless-hub-motor-for-electric-scooter/161543341214?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20131003132420%26meid%3D2a88fff931fe4075958a2ee674527cde%26pid%3D100005%26prg%3D20131003132420%26rk%3D5%26rkt%3D6%26sd%3D161541051748&rt=nc
14:51 Mister 400-1200rpm*
14:59 RifRaf .weather 2452
14:59 makepi RifRaf: North Waltham, MA: Overcast, 16.1 F (-8.8 C), 30.14(0), Feels Like: 16 F (-9 C), Humidity 76%, WindFrom the WNW at 2.1 MPH Gusting to 5.0 MPH - Last Updated on January 6, 3:39 PM EST http://goo.gl/On0mvX
14:59 RifRaf wrong
15:12 codepython777 Hyratel: doesnt it make more sense to control the servos on the acrobatics 4wd using a usb motor controller?
15:23 deshipu Mister: that would be pretty bad for a scooter
15:26 Mister deshipu: hmm, so you know a regulator that would work with two of these?
15:26 Mister what is that called btw..
15:28 Mister the part hat controls power to the motors
15:44 deshipu no idea
16:01 Veverak fuuu
16:01 Veverak deshipu: thought about getting involved in that competition for devconf
16:03 codepython777 does anyone know of good motors like these with encoders: https://www.servocity.com/html/313_rpm_hd_precision_planetary.html#.VKxWTitDGSo ?
16:04 Veverak but not really sure about that
16:07 deshipu Veverak: competition?
16:07 deshipu ah, openshift
16:07 deshipu I need to get my ass in gear and actually setup something on my openshift account
16:07 deshipu one day
16:07 Veverak :D
16:08 Veverak well I thought about making it calc my CAD calculations somehow in usable way
16:11 armyofevilrobots http://www.aliexpress.com/item/Second-hand-Namiki-DC-hollow-cup-planetary-gear-motor-12v-120-with-encoder-made-in-Japan/1687111705.html
16:16 codepython777 Hyratel: I want encoders on my motors :)
16:20 codepython777 armyofevilrobots: nice motor :)
16:22 armyofevilrobots CHEAP.
16:29 codepython777 armyofevilrobots: I'm looking to add quadrature encoders on this one: https://www.servocity.com/html/313_rpm_hd_precision_planetary.html#.VKxc6CtDGSq
16:29 codepython777 any ideas?
16:33 armyofevilrobots http://www.aliexpress.com/item/Encoder-600P-R-Incremental-Rotary-Encoder-AB-phase-encoder-6mm-Shaft-free-shipping/2038810675.html
16:44 codepython777 armyofevilrobots: I'd like to buy something - but not from aliexpress :)
16:46 armyofevilrobots why not?
16:47 codepython777 armyofevilrobots: Return policy? time?
16:47 armyofevilrobots Ah well :\ Can’t fix either of those.
16:47 armyofevilrobots I have had pretty good luck myself, but you do have to be careful what you order, and it takes forever.
16:53 DagoRed codepython777: Look at the c1 from hardkernel
16:53 DagoRed .g hardkernel c1
16:53 makepi DagoRed: http://www.hardkernel.com/main/products/prdt_info.php
16:53 DagoRed .shrink
16:53 makepi DagoRed: http://goo.gl/LJysmo
16:59 codepython777 DagoRed: how does a c1 help?
17:49 Hyratel codepython777, the actobotics 4 wheeler does NOT HAVE SERVOS. they're gearmotors
17:50 Hyratel Mister, that means it loses torque below that
17:52 armyofevilrobots No, the no-load RPM is rated at 400-1200 rpm (depending on how the motor is set up). You get _MORE_ (or technically, any at all) torque below that speed. It’s the MAX speed that is between 400-1200 depending on setup.
19:10 codepython777 Hyratel: I thought quadrature encoders are independent of the motor type? I was looking for a 4WD with motors + quadrature encoders.
19:18 Hyratel they are
19:19 Hyratel encoders are a module you stick on the gearbox or motor spindle and act as a tachometer type sensor
20:12 codepython777 Hyratel: Why did you say this -> "(6:29:10 PM) Hyratel: codepython777, the actobotics 4 wheeler does NOT HAVE SERVOS. they're gearmotors"
20:12 Hyratel you keep calling motors servos.
20:13 Hyratel see your hilighting me earlier
20:13 codepython777 ah ok
20:13 Hyratel very important difference
20:13 codepython777 Hyratel: I still cant find a 4WD kit with quadrature encoders
20:14 Hyratel you need to find a 4 wheel kit without motors
20:14 Hyratel or roll your own kit
20:14 Hyratel /frame
20:14 Hyratel and build it with motors that have encoders
20:14 Hyratel you don't actually need quad coders
20:15 Hyratel you can get by with a single coder because you know the rotation direction
20:15 codepython777 i would prefer 2 encoders
20:15 Hyratel coders tell RPM
20:15 codepython777 and a usb controller with 2 motor controls
20:15 Hyratel quad encoders tell direction and RPM
20:15 Hyratel stopsign
20:15 Hyratel https://dl.dropboxusercontent.com/u/33593534/images/Robot/DSCN2012-1k2.jpg
20:16 Hyratel you don't understand your own design requirements
20:16 Hyratel ok, lets get back to basics
20:17 Hyratel you need a 4 wheeled skidsteer chassis with a 3kg payload capacity
20:17 codepython777 yes
20:17 Hyratel you need a wireless control of this chassis
20:17 codepython777 no, that i have already.
20:17 Hyratel no, you don't
20:17 codepython777 I need to run this using a raspberry pi type soc.
20:17 Hyratel why a raspi?
20:17 Hyratel what does a raspi do that something else can't?
20:18 codepython777 Hyratel: It can do vision, sound, light, ...
20:18 Hyratel you need to step back from your hardware
20:18 Hyratel you need a 4 wheeled skidsteer chassis with a 3kg payload capacity
20:18 Hyratel you need a wireless control of this chassis
20:18 codepython777 no
20:18 Hyratel yes
20:19 Hyratel you're getting caught down in the weeds.
20:19 codepython777 k, I need a 4 wheeled skidsteer chassis with a 3kg payload capacity
20:19 Hyratel you need to back the truck up
20:19 Hyratel look at your design requirements
20:19 Hyratel are you going to DO vision processing?
20:19 codepython777 I have a ARM based Soc on top of this chasis , which needs to precisely be able to drive this chasis
20:19 codepython777 yes, that is why i need the chasis.
20:19 Hyratel do you already know how do vision processing with a raspi?
20:20 Hyratel can you do vision processing without the robot yet?
20:20 Hyratel why does it need vision processing?
20:20 codepython777 Hyratel: yes, that is what i need to start testing, when things are in motion
20:20 Hyratel is this for a challenge?
20:20 codepython777 no
20:20 codepython777 its for a school project :)
20:20 Hyratel a simple design that works is more impressive than a complex one that doesn't
20:21 codepython777 Hyratel: whats simpler than a ARM based soc to do Vision?
20:22 Hyratel if you're doing vision processing, why do you need wireless control? safety overrides?
20:22 Hyratel also, for your radio, get a wireless xbox 360 controller
20:22 Hyratel and a PC USB dongle
20:24 Hyratel codepython777, then your constraint isn't "I need to use a raspi for vision"
20:24 Hyratel it's "I need to do local vision processing"
20:25 Hyratel see the difference?
20:25 Hyratel your constraints aren't "what's my solution", they're "what needs to happen?"
20:26 Hyratel also "completed vehicle needs to be wet-weather safe"
20:27 codepython777 Hyratel: k
20:27 codepython777 Hyratel: xbox controller?
20:28 Hyratel and the "can I do local vision" is "yes: raspi"
20:28 Hyratel it's how I did it with the Hormes robot
20:28 codepython777 I'm driving this chasis with my arm soc, done. The only thing i need is how the arm soc controls the motors, precisely
20:28 Hyratel that's the one I've been linking pictures of
20:28 Hyratel no, you're doing vision proc with the ARM SOC
20:29 Hyratel the motor control is a big [ ? ] right now
20:29 Hyratel but you don't get a coin for punchhing it
20:29 codepython777 k
20:30 Hyratel also
20:30 Hyratel "I have a raspi onboard. how do I control the motors?"
20:30 codepython777 Since i have an arm soc onboard, i was thinking of using a motor controller + usb to control the motors using the arm soc.
20:30 Hyratel not "how do I control the motors with a raspi"
20:30 Hyratel reasonable
20:31 Hyratel you see how the thinking approach differs though?
20:31 codepython777 Hyratel: I think i was just not explaining things well. Thanks for pointing this out.
20:32 codepython777 Btw, your bot looks impressive. What is it for?
20:32 Hyratel so your present constraints are as follows
20:32 Hyratel for fun
20:32 Hyratel "4 wheeled skid steer chassis with payload of 3kg"
20:32 Hyratel "local vision proc"
20:33 Hyratel "wireless control/override"
20:33 Hyratel "wet weather safe as completed"
20:33 Hyratel doe sthat about cover it?
20:34 codepython777 I think so, not sure about the "override" part?
20:34 Hyratel if it goes rogue you can hit a panic-stop
20:35 Hyratel are there any other constraints I should know about?
20:35 Hyratel budget?
20:37 codepython777 < $500 preferably
20:38 Hyratel Hormes is $600 all-in
20:38 codepython777 Hyratel: wow
20:38 codepython777 Hyratel: For the acrobatics kit, i could not even find a motor controller that was usb and was cheap.
20:38 codepython777 Hyratel: do you have a pi or arm soc in there?
20:39 Hyratel you're misunderstanding motor controllers
20:39 Hyratel nope! arduino uno
20:39 codepython777 What am i missing?
20:39 Hyratel USB host shield
20:39 Hyratel that's it
20:40 Hyratel thats the secret sauce
20:40 Hyratel https://dl.dropboxusercontent.com/u/33593534/images/Robot/DSCN2015-1k2.jpg
20:40 Hyratel cheap, rough and tumble
20:40 codepython777 brb
20:46 codepython777 back
20:46 codepython777 Hyratel: https://www.sparkfun.com/products/9947?gclid=COK_o67qgMMCFafyMgodrHAAKw
20:55 Hyratel yes, that'll do
20:55 Hyratel why do you need local vision proc though?
20:57 Hyratel the point of the USB host is to avoid the need for an oboard computer
21:08 codepython777 Hyratel: I'm doing some experiments with vision. I need to make sure it will work on a chasis. So in my case, its vision because of which i need to build the chasis (testing).
21:08 codepython777 since i have the onboard - i want to minimize/simplify my requirements around it
21:09 Hyratel ok, thsoe are good reasons
21:09 codepython777 Ideally, I would like to have precision in movements. Move the wheels 60 degree angle
21:10 codepython777 with your arduino design, what motors did you use? how do you control them?
21:10 codepython777 what battery?
21:21 Hyratel uh, how aboutlooking at the pictures I posted
21:21 Hyratel the motors are CIMs, into CIMple gearboxes (4.6:1
21:27 codepython777 are you using a car battery? :)
21:28 codepython777 surge current ? continuous current on your CIMs?
21:30 Hyratel 1/2 HP each, 30 A sustained surge
21:30 Hyratel er
21:30 Hyratel 30A peak susstained heavy laod
21:31 Hyratel 18AH motorcycle battery
21:33 codepython777 continuous current = 30A?
21:33 codepython777 or maybe 3A?
21:37 Hyratel those motors will do 30A continuous
21:38 Hyratel 12v *30A = 1/2 HP
21:38 codepython777 wit 30A continuous at 12v- wont the battery drain out pretty soon?
21:38 Hyratel I said the motors will do it
21:38 Hyratel it's an 18 AH battery
21:39 Hyratel and thaty's not the actual peak
21:39 Hyratel that's just what the motors will do
21:39 codepython777 you have 4 or 2 motors?
21:40 Hyratel 2
21:40 Hyratel 1 per side
21:42 codepython777 Hyratel: http://www.superdroidrobots.com/shop/item.aspx/4wd-all-terrain-compact-robot-platform-ig32-dm/1496/
21:42 codepython777 seems like i can configure the motors and controller here.
21:54 codepython777 Hyratel: any thoughts on this platform?
21:54 codepython777 of course they dont fit my budget.
21:55 Hyratel not really
21:55 Hyratel how much fabrication skill do you have?
21:55 Hyratel because a plywood platform is more than enough
21:56 codepython777 Hyratel: i have used a 3d printer, other than that none.
21:56 codepython777 Hyratel: if i want precise movements, dont my controller and motors anyway get expensive?
21:56 Hyratel can you put two screws into a board and have them line up?
21:57 codepython777 yes :)
22:02 codepython777 Hyratel: ?
22:03 Hyratel https://www.sparkfun.com/products/12175
22:04 Hyratel use as motor mount on plywood for actobotics motors
22:06 codepython777 https://www.sparkfun.com/products/13141 + something?
22:06 codepython777 with actobotics, the only problem i have is that the motors are not the ones i want
22:06 Hyratel you're not listening
22:07 codepython777 Hyratel: you are asking me to mount the motors on the plyboard myself :)
22:07 Hyratel yes.
22:07 Hyratel or, get some motor mounts, and a few actobotics rails
22:07 codepython777 why not then just use acrobotics piece that can take the motors?
22:07 Hyratel use plywood as the main structure
22:08 Hyratel or are you afraid to try and /design/ something
22:08 Hyratel you want a turnkey chassis and you want cheap.
22:08 codepython777 your suggestion sounds good actually :)
22:08 Hyratel good, cheap, turnkey. you may choose any two
22:09 codepython777 good + cheap - but i dont want to use ply. Metal would be nice.
22:09 Hyratel use ply
22:09 Hyratel you said you didn't have any fabrication experience
22:09 codepython777 I could just use the same actobotic rails that is in that kit?
22:09 codepython777 3 pieces
22:09 Hyratel stopsign
22:09 codepython777 it wont be flexible, but work?
22:09 codepython777 k - stop :)
22:10 Hyratel take a flat peice fo plywood
22:10 codepython777 https://www.sparkfun.com/products/13141 - why not these rails?
22:10 Hyratel mount two rails longwise along the sides.
22:10 codepython777 all i have to do is add nuts
22:10 Hyratel https://www.sparkfun.com/products/12250
22:10 codepython777 k - yes
22:11 Hyratel now build your electronics on top of the plywood
22:13 codepython777 sparkfun doesnt sell robot wheels!
22:14 Hyratel bullshit
22:14 Hyratel https://www.sparkfun.com/categories/180
22:15 codepython777 https://www.sparkfun.com/products/10555
22:16 Hyratel what kind of terrain are you hitting?
22:16 codepython777 grass + roads + curbs
22:16 Hyratel you're not doing curbs in that size robot
22:19 codepython777 those wheels are 12cm diameter = 5". I need a 12" channel. I guess it won't climb a curb = 16" with speed?
22:19 Hyratel not even with 4 3/4" tires
22:19 codepython777 Hyratel: k- give up on curb
22:19 Hyratel do you mean a hard curb or a ramp curb?
22:20 codepython777 Hyratel: I can live with grass + road
22:20 codepython777 Let me build my parts list :)
22:20 Hyratel Hormes, even with 10" wheels, can barely do curbs
22:22 codepython777 Hyratel: http://notes.io/LmR - can you edit this?
22:22 Hyratel nope
23:37 Hyratel http://www.andymark.com/product-p/am-2239.htm