#robotics Logs

Dec 03 2011

02:14 r0b-_ any tips on building a line following obot?
02:40 the_jester greets
02:54 thylyn hexbugs seems kind of cheap
02:55 thylyn i wonder what I could get for $299
03:18 the_jester alot more than that
10:25 r0b-_ line follower sound fun>?yea i think a simple line follower would work fine
10:26 rue_bed yes
10:26 rue_bed its a good starter project, there is a lot of things you can do with it
10:26 rue_bed you dont even need a microcontroller
10:27 r0b-_ what do you mean?
10:27 rue_bed r0b-_, do you have any parts to start
10:27 r0b-_ not really
10:27 rue_bed ok
10:27 rue_bed have you ever programmed microcontrollers?
10:27 r0b-_ yea
10:27 rue_bed ok
10:27 r0b-_ im pretty familiar with arduino :)
10:28 rue_bed how much of a budget do you have for building something?
10:28 rue_bed $1? $100?
10:28 r0b-_ 50$
10:28 rue_bed ok
10:28 rue_bed do you want to build or buy most of the mechanics?
10:28 r0b-_ id prefer to buy
10:28 rue_bed hmm, ok
10:29 r0b-_ id build the chassis though
10:29 rue_bed ok, may I suggest a 3 wheeled design?
10:29 rue_bed o
10:29 rue_bed o
10:29 rue_bed o
10:29 rue_bed with the left two wheels being independently driven
10:30 rue_bed you can choose where the front is
10:30 rue_bed its easy to control
10:30 r0b-_ you mean like 2 drives and a ball caster?
10:30 rue_bed yes
10:31 rue_bed you would start by finding 2 hobby servo motors, possibly premodified for continious rotation
10:32 rue_bed there are wheels sold that fit servos, but if you like I can show you how to make some of your own with sheet metal and automotive O rings
10:32 r0b-_ hmmm
10:32 Steffanx Why servo's?
10:32 r0b-_ i have access to a dremel :)
10:33 rue_bed because they have built in motor drivers, you can remove them later if you want to drive them youself,
10:33 rue_bed and their geared
10:33 r0b-_ and they are simpler
10:33 rue_bed r0b-_, to make the wheels you just need a drill and tin sheers
10:33 rue_bed or you can buy them
10:33 rue_bed or
10:33 r0b-_ how about wooden wheels lol
10:34 rue_bed if you have an old HP printer, they have rollers in them that make great wheels
10:34 r0b-_ k
10:34 r0b-_ well brb
10:34 rue_bed absolutly, tho I suggest keeping wood and cardboard out of you robot builds
10:34 rue_bed ok, I'm gonna go take my shower
10:35 r0b-_ i have a 3.5x10 inch acrylic sheet
10:35 r0b-_ that i could maybe use as a base
10:46 r0b-_ Steffanx why not use servos?
10:47 Steffanx No, I just wondered why servo's :)
10:47 Steffanx And not standard motors with gears
10:48 r0b-_ hmmm
10:48 r0b-_ price also
10:50 r0b-_ pservos are cheaper
10:55 r0b-_ ok 13$ per servo
10:55 r0b-_ for parallax cont rotartion servos
10:56 r0b-_ vs 15$ each for motors
10:58 rue_house yea, take advantage of either mass marketing or mass consumption (via waste from consumers)
10:58 rue_house how thick is the acrylic sheet?
10:59 r0b-_ bout 1/16th of an inch
10:59 rue_house thats ok for a small robot, or if you make spaced layers
10:59 r0b-_ well i think i have some stepper motors some where
11:00 rue_house drilling it is trickey, its brittle
11:00 r0b-_ but they are about fist size :)
11:00 rue_house you dont want steppers on a battery operated robot
11:00 rue_house about how big would you like the robot to be?
11:00 r0b-_ http://www.robotshop.com/solarbotics-gm3-gear-motor-3.html
11:00 Tom_itx HUGE!
11:00 r0b-_ maybe 5x5
11:00 r0b-_ 4x6 :)
11:00 rue_house but then you need to buy motor drivers too
11:01 r0b-_ 25/60 lol
11:01 Tom_itx 13' mech
11:01 rue_house if you use those gearboxes
11:01 rue_house heh
11:01 r0b-_ yea lol
11:02 rue_house 4x6 is fine
11:02 r0b-_ i dont want a big bot
11:03 rue_house yup, thats all fine
11:03 Tom_itx thunder storm early this morning
11:04 Tom_itx odd for December
11:04 rue_house r0b-_, are you able to make a list from what I'm saying?
11:05 r0b-_ yea
11:06 r0b-_ well i was thinking use the thinner stuff ang just sandwich the motors between it
11:06 r0b-_ like have one sheet on top and another on the bottom
11:06 r0b-_ and make like a box
11:07 r0b-_ you know what i mean
11:08 r0b-_ or buy http://www.robotshop.com/pololu-round-chassis-1.html
11:10 r0b-_ though at 2$ a sheet for this thin acrylic
11:10 r0b-_ i can get 2 bases
11:10 r0b-_ its a 7x 10 sheet
11:11 r0b-_ errr 8x10
11:12 r0b-_ so
11:12 r0b-_ atleast its cheap
11:24 rue_house boxbeam, good plan
11:24 rue_house you can get lexan from a glass shop, its easier to drill and cut, its not brittle
11:25 rue_house you can get scraps as small as 12"x12"
11:25 rue_house almost free
11:25 Tom_itx big enough to make an etch tank
11:25 rue_house <rue_house> yea, take advantage of either mass marketing or mass consumption (via waste from consumers)
11:25 rue_house Tom_itx, sssh
11:26 r0b-_ lol
11:27 r0b-_ well
11:28 rue_house its worth phoning to ask
11:28 r0b-_ for a motor driver do i need a prefabbed board or just an IC?
11:28 rue_house there are both
11:28 rue_house generally its a bunch of extra effort
11:28 rue_house if its your first robot I suggest using servos
11:29 r0b-_ ok
11:30 rue_house ok to the shop, robotics in 30 mins
11:31 r0b-_ ok
11:31 r0b-_ lol
11:36 r0b-_ mmm hes not back so i will vanish!
11:41 Tom_itx rue_shop
11:41 Tom_itx what are we gonna do today?
11:48 r0b-_ i told you hes gone :)
11:49 thylyn Anyone know of any robots that act autonomously and are around $300
11:50 rizlah thylyn, Why not make one=
11:50 Tom_itx many are less
11:52 r0b-_ i plan on making one
11:52 r0b-_ :)
11:54 r0b-_ that follows a line
11:54 r0b-_ simple but complez
11:56 r0b-_ im gonna assume 60rpm is fast?
12:53 r0b-_ try #android ?
12:58 thylyn [12:41] <rizlah> thylyn, Why not make one=
12:58 thylyn I don't have a garage and tools and soddering and all that
13:06 ace4016 solder*
13:13 Tom_itx get some
13:14 r0b-_ i have tools solder and such
13:14 r0b-_ so i could build
13:14 r0b-_ i just bought a new set of hand tools
13:14 r0b-_ a ratchet and sockets and some screw drivers hex keys and i have a dremel
13:23 r0b-_ the ratchet isnt worth a damn lol
13:43 Tom_itx rue_house can relate to this http://www.youtube.com/watch?feature=player_embedded&v=nn2h3_aH3vo
13:47 thylyn the NAO costs 13 thousand dollars.
13:47 thylyn and hexbug costs $11.99
13:47 thylyn seems to me there should be a mid-tier robot out there
13:52 r0b-_ hmmm
13:52 r0b-_ DIY!
13:52 thylyn ?
13:52 r0b-_ build it yourself
16:50 r0b-_ hi rue_house
18:09 Skwint thylyn, you could pay someone to paint a hexbug in a custom colour and charge you $288.01 for it?
18:10 Skwint that meets every requirement you have mentioned so far :p
18:10 Skwint and I'm 5 hours late to the conversation - joly good!
18:36 diegoviola hi
18:36 diegoviola have you guys seen this: http://www.youtube.com/watch?v=cFVlzUAZkHY
18:36 diegoviola what do you think?
18:41 diegoviola http://www.youtube.com/watch?v=sGqDLUAy2Tc
19:43 Birdee woah
19:43 Birdee that's creepy
20:09 diegoviola i like her smile: http://ompldr.org/vYmtwcQ
20:37 zhanx wine party is over
20:37 zhanx it rocked
20:37 zhanx 37 different wines
20:39 rue_house r0b-_,
20:39 r0b-_ ?
20:40 zhanx rue_house: no mail
20:42 rue_house hmm
20:42 rue_house I sent it air
20:42 rue_house did you check the air?
20:42 anx looks outside and see s
20:45 rue_house look for a small package folded up to a shape like an airplane
20:45 rue_house might be on the ground somewhere
20:45 zhanx lol there is snow out
20:46 rue_house bingo, problem found
20:46 zhanx yep
20:54 rue_house zhanx, you might be interested
20:54 rue_house I just wrote a handy program
20:54 rue_house <rue_house> it makes a file called version.h
20:54 rue_house <rue_house> #define version "1.6.6"
20:54 rue_house <rue_house> which has content that looks like that
20:54 rue_house <rue_house> every time you run the program, it increments the version
20:54 rue_house <rue_house> A.B.C C has the range 0-9 B has the rance 0-99 A has the range 0-999
20:54 rue_house <rue_house> would you like a copy?
20:54 rue_house <rue_house> it can be called in a makefile! ;)
20:54 zhanx yes
20:54 rue_house ok
20:54 rue_house 1 min
20:54 zhanx k
20:56 rue_house http://ideone.com/OymsU
20:57 anx files as a func
20:59 rue_house I think with that version you need to create the initial file, I'm working on that
21:09 rue_house zhanx, interested in a program that can create a new version.h file if it dosn't exist?
21:14 rue_house http://ideone.com/yaUlx
21:14 rue_house zhanx, ^^^ that version is friendlier
21:15 r0b-_ well rue_house
21:15 r0b-_ as soon as i figure out how to do a ramp up PWM :)
21:15 r0b-_ i will have my controller done
21:19 rue_house ok
21:20 r0b-_ which i think i have the code figured out
21:28 r0b-_ im simulating using a Basic Stamp though
21:28 rue_house heh
21:28 r0b-_ yea
21:28 rue_house did you decide on hardware?
21:28 r0b-_ what do you mean?
21:29 rue_house motors, wheels etc
21:29 r0b-_ yea
21:29 r0b-_ i did
21:29 rue_house what did you find?
21:30 r0b-_ well i have nothing hear to use
21:30 rue_house well whats the plan?
21:30 r0b-_ but i can get some servos locally
21:30 r0b-_ simple 2WD wheeled platform using dual gear motors
21:31 rue_house yup, using servos it sounds, what for wheels?
21:31 rue_house you need some sensors for the line too
21:31 rue_house reflective IR maybe
21:32 r0b-_ yea
21:34 rue_house did you find wheels
21:34 rue_house ?
21:35 r0b-_ not yet
21:35 r0b-_ someone told me to make a closed look system but i think that will just add complexity to a simple robot
21:36 r0b-_ id really like to know how to do variable PWM on a basic stamp in sim
21:37 rue_house its a clossed loop, but its simple
21:37 rue_house you go straight unless you see the line on one side, then you turn till you dont see if anymore
21:38 r0b-_ well is what i was meaning is they want me to make the motors act like servos
21:38 r0b-_ using encoders and such
21:39 r0b-_ so like if it stops on a hill it wont move
21:40 r0b-_ http://www.pololu.com/catalog/product/1217
21:41 r0b-_ i have a simple forward/reverse program running in sim
21:41 r0b-_ using a BS2 and L293D
21:41 r0b-_ along with LEDs to indicate direction
21:45 rue_house nono
21:45 rue_house thy meant that you could linearly varry the motor speed based on the position error
21:45 r0b-_ ??
21:45 rue_house with the servos, what would normally be a position input, changes the servos speed
21:45 rue_house with continious rotation modified servos you can controll direction and speed (not position)
21:48 r0b-_ im talking about using position encoders on a gear motor
21:48 rue_house no
21:48 rue_house dont do that, not for your first robot line follower
21:50 r0b-_ i guess im gonna have to get my arduino
21:50 r0b-_ and use the serial to test the code
21:51 r0b-_ :)
21:58 r0b-_ http://pastebin.com/WD0LNxrG
21:58 r0b-_ tgheres some of the code
22:01 rue_house you know you dont need a computer to make a line follower?
22:02 rue_house then again, with one its easier to use the servos
22:05 r0b-_ what you mean
22:05 r0b-_ i dont need a PC
22:06 rue_house an ardiono. a basic stamp, a PIC, an avr
22:06 rue_house you can do it with a basic logic chip
22:06 Tom_itx a 555
22:06 rue_house no
22:06 rue_house !assist circuits
22:06 tobbor Possibly http://eds.dyndns.org/~ircjunk/circuits
22:06 rue_house http://eds.dyndns.org/~ircjunk/circuits/linebot.jpg
22:07 rue_house that dosn't include the motor drivers
22:38 r0b-_ well i got the code worked out almost
22:55 r0b-_ ok perfect
22:55 r0b-_ cant wait to get the motors
22:55 rue_house :)
22:56 rue_house want to know how to make sheetmetal wheels?
22:56 r0b-_ hmmm
22:57 b-_ used leds to
22:58 r0b-_ it will be fune to get this working
22:59 r0b-_ seeing it move :)
23:00 r0b-_ heh one motor works fine
23:00 r0b-_ should be easy to get 2 motors
23:41 r0b-_ wish i had a motor
23:41 r0b-_ to visualise
23:41 rue_house hehe
23:41 b-_ cant do not
23:46 r0b-_ shit
23:46 r0b-_ differential drive will be fun :)
23:47 r0b-_ to impliment into code
23:48 r0b-_ well i really dont need to ramp up the power
23:54 r0b-_ Thttp://www.robotmarketplace.com/products/0-PL1594.html these are the motors im gonna use
23:54 r0b-_ or the metal gear ones you think would be better?