Society of Robots - Robot Forum

General Misc => Misc => Topic started by: madsci1016 on December 30, 2009, 02:57:55 PM

Title: Finally started documenting my current robot.
Post by: madsci1016 on December 30, 2009, 02:57:55 PM
Details on my blog:

http://www.billporter.info/?p=95 (http://www.billporter.info/?p=95)

(http://www.billporter.info/wp-content/uploads//2009/12/IMG_2348-300x225.jpg)

"It is powered by 2 Li-Ion packs i built myself; has GPS, 3 axis compass, Xbee 900Mhz radio and an Axon as the main MCU. Eventually it will have an array of ultrasonic range finders for obstacle avoidance."

What do you think?
Title: Re: Finally started documenting my current robot.
Post by: z.s.tar.gz on December 30, 2009, 03:15:14 PM
Very professionally done, or at least looks of it.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on December 30, 2009, 03:32:24 PM
Thanks.

I guess I am good, or just good at faking it, lol.
Title: Re: Finally started documenting my current robot.
Post by: SmAsH on December 30, 2009, 05:09:07 PM
Robot porn! Cover your circuits!
That robot looks delicious, well done on it mate!
Where did the chassis come from, bought or made?
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on December 30, 2009, 06:36:01 PM
Robot porn! Cover your circuits!
That robot looks delicious, well done on it mate!
Where did the chassis come from, bought or made?

Quote from: www.billporter.info
The base chassis is a Lynx-motion 4WD rover body.

bought, and a bit over-priced, especially when i had to replace two motors with ones that I could attach encoders to.

http://www.lynxmotion.com/Category.aspx?CategoryID=1 (http://www.lynxmotion.com/Category.aspx?CategoryID=1)
Title: Re: Finally started documenting my current robot.
Post by: SmAsH on December 30, 2009, 07:00:02 PM
A bit overpriced :o
How much would you say this project has cost all up so far?
Title: Re: Finally started documenting my current robot.
Post by: z.s.tar.gz on December 30, 2009, 09:07:34 PM
200 bucks for a chassis!? Crap! That's my whole robot!
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on December 30, 2009, 10:47:27 PM
A bit overpriced :o
How much would you say this project has cost all up so far?

Too much. If i add it up I can no long be blissfully ignorant over how much i have spent. It is all worth it though, i have learned many things that have come in handy(and impressed the higher-ups) at my (well paying) job (that i was very lucky to find in this economy.)  The batteries i scored on because i got the a few dozen Li-ion cells donated to me and i just spent $10 per pack assembling them with protection circuits. 14.4V 2.2aH packs, which are not bad at all for $10 bucks spent per pack. A few other things i took from my girlfriend's mothballed senior design robot.

200 bucks for a chassis!? Crap! That's my whole robot!

Yes, but can your robot navigate rough terrain, communicate over 4 miles, and drive itself using GPS, inertial, and feature based navigation? ( I am working on the last two next). While 200 is a bit much, it is a well built chassis with motors and nice tough rubber tires. The plastic top is machined for many different types of cut-outs to add servos and such. I would recommend it to anyone trying to build a robot NOT limited to tile floors and sidewalks.

Like i said, i feel it is all worth it. I partially rationalize it but not buying video games, or new computer parts, staying off woot.com, etc
Title: Re: Finally started documenting my current robot.
Post by: Joker94 on December 30, 2009, 11:45:15 PM
That is awsome :o

I hope to have that kind of money soon(well not as much but it wiill be more) ;)

I bet you i impressed the higher up :D

Keep up the great work and the posting

Joker94
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on December 31, 2009, 09:30:44 AM
Keep up the great work and the posting

Joker94

Will do. I need to add some more about what I already have built. When i do, you guys will be the first to know.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on January 01, 2010, 12:59:38 PM
part 2 posted

http://www.billporter.info/?p=116 (http://www.billporter.info/?p=116)

"Part 2 of my documenting of my robot project focuses on the just completed “Smart Motor Controller”. I call it a smart controller because, unlike other motor controllers on the market, mine utilizes feedback from the motors to precisely set wheel speeds and report back how far the robot has traveled."

Also, i am thinking about selling a kit to build a motor-controller like mine, and maybe open-source-ing the code. It doesn't seem there are any commercial products like this (at least cheap ones). Would anyone be interested in if if i were to sell / open source it?
Title: Re: Finally started documenting my current robot.
Post by: Joker94 on January 01, 2010, 05:55:57 PM
Selling/ open sourcing it would be awsome as alot of teenage robot builders dont have the money for what your talking about so selling it and or open sourcing it would be great.
Title: Re: Finally started documenting my current robot.
Post by: SmAsH on January 03, 2010, 12:50:48 AM
Madsci, will you be releasing source code at all?
Title: Re: Finally started documenting my current robot.
Post by: little-c on January 03, 2010, 04:29:50 AM
I want one!

purely from lazyness. and a desire to not incinerate my fingers on mosfets again!
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on January 03, 2010, 09:01:00 AM
Madsci, will you be releasing source code at all?

More then likely. I am an EE and really didn't have formal education in programming beyond the basics (and assembly, yuck) i self taught the high order stuff. I am in the process of having a real CS look over my code and give me some pointers.

I would love this to be my first major contribution to the community, but I am too proud, and want to make it a little more professional before i do.

I take it you are interested in it, Smash?
Title: Re: Finally started documenting my current robot.
Post by: SmAsH on January 03, 2010, 04:17:37 PM
Quote
I take it you are interested in it, Smash?
Well, it would be an interesting code to look over, i have a weird thing where i see an awesome robot an i instantly want to see the code... Anyone else get that?
But it would make an awesome robot for my more advanced years :)
Title: Re: Finally started documenting my current robot.
Post by: Hertz32 on January 09, 2010, 07:11:22 AM
Quote
i have a weird thing where i see an awesome robot an i instantly want to see the code... Anyone else get that?

i do 2
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on January 09, 2010, 11:06:23 AM
Alright, since I can't argue with that...

Code posted.   http://www.billporter.info/?p=127 (http://www.billporter.info/?p=127)

Please feel free to leave a comment on my site. It is starting to get lonely. :-(

Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on February 06, 2010, 01:25:28 PM
Update on my work:

http://www.billporter.info/?p=174 (http://www.billporter.info/?p=174)

"Compass Woes"
Title: Re: Finally started documenting my current robot.
Post by: dunk on February 06, 2010, 02:24:58 PM
hey Madsci1016,
a common solution to the magnetic effect of motors and power wires is to put your compass up on a mast away from all the other electronics.
something non magnetic like plastic tubing or something.
not the prettiest solution but it works.

dunk.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on February 06, 2010, 02:37:47 PM
Well, if you look at my pictures, that's pretty much what i did. I put it up on 3/4" plastic stand-offs.
Title: Re: Finally started documenting my current robot.
Post by: dunk on February 08, 2010, 02:46:43 PM
yea, if you continue to have problems, increase the distance.
most pictures i've seen of people using magnetic compasses tend to have the compass on a mast over a foot long.
hopefully you'll be good with your current solution.

dunk.
Title: Re: Finally started documenting my current robot.
Post by: Hertz32 on February 08, 2010, 03:05:49 PM
Quote
a common solution to the magnetic effect of motors and power wires is to put your compass up on a mast away from all the other electronics.
something non magnetic like plastic tubing or something.
not the prettiest solution but it works.

who said robots had to be preety!?  :D
Title: Re: Finally started documenting my current robot.
Post by: Admin on February 11, 2010, 02:53:31 AM
For my robot fish, just having my batteries within a foot distance away from the compass totally warps the magnetic field. So calibrate your compass after everything is already positioned.

Oh, and if your bot drives up to your fridge, or passes over a metal beam under the floor, expect magnetic field warping . . .

For fine angle positioning, use a gyro. To account for gyro drift, use a digital compass as a global reference. aka Kalman filter :P
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 06, 2010, 10:34:14 PM
WOOOOOO!!!

Ok, so i'm a little excited.

I just got back from watching SAGAR complete it's first autonomous mission. It ran a circuit of waypoints around my parking lot.

(http://www.billporter.info/wp-content/uploads//2010/04/mission3.png)

I'll have to do it again to capture video, I ran it at 11pm local time, in the dark. I had just finished coding the nav functions and couldn't wait to test. It worked decently, other then the Venus GPS seems to be garbage, and I had to stop and move it a bit so as not to hit a car or curb.

EDIT: more details on how it ran and how it works, here: http://www.billporter.info/?p=192 (http://www.billporter.info/?p=192)
Title: Re: Finally started documenting my current robot.
Post by: Ro-Bot-X on April 07, 2010, 05:30:49 AM
Wow! Now you can o to a RoboMagellan competition. Congrats!
Title: Re: Finally started documenting my current robot.
Post by: Admin on April 07, 2010, 06:55:32 AM
Wow! Now you can o to a RoboMagellan competition. Congrats!
Well not quite . . . in RoboMagellan, they put obstacles between waypoints . . .
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 07, 2010, 07:19:18 AM
In a future addition, I'm going to add an array of ultra-sonics to the front for obstacle avoidance and path planing.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 13, 2010, 05:47:35 PM
Just captured a video of SAGAR's new operator panel. Check it out.

EDIT: WHOA!! SoR rewrites the youtube embed, so make sure to select HD when you watch this.

SAGAR Autonomous Robot Runs First Mission under Labview Control (http://www.youtube.com/watch?v=lHI_m-GH_Qc#ws,hd=1)

Details here:

http://www.billporter.info/?p=195 (http://www.billporter.info/?p=195)
Title: Re: Finally started documenting my current robot.
Post by: parallax on April 15, 2010, 06:34:49 PM
You are doing some really incredible work here, madsci1016! Hats off to you!

I also would like to point out how incredibly great it is that you and your girlfriend can collaborate on projects like this! My GF is a fan and a supporter of my endeavors, but a techy she is not. I'm a little jealous  ;)

I would love to know more about how you are implementing the orientation sensor. I plan on using one for my hexapod before too much longer and have been researching them in depth. What I would love to know specifically:

*What hardware are you using?
*What kinds of issues have you run into?
*What kinds of solutions for those issues have you tried or plan on trying?
*Would you do anything differently?

Who knows? Perhaps we can help you with the noise issues you mentioned...
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 16, 2010, 09:40:49 AM

the orientation data comes from a Honeywell HMC6343 compass. It has a 3 axis accelerometer built in, and provides roll and tilt data. The only issues is the noise, something that all solid state accelerometers have.

The fix is to combine accelerometer date with solid state gyro data, as gyros smooth out the noise, and accelerometers fix gyro drift. I plan to add gyros to my robot at some point, to smooth out the data.

There are ready made open source products that combine gyros and accel for clean orientation data. http://store.diydrones.com/product_p/kt-arduimu-20.htm (http://store.diydrones.com/product_p/kt-arduimu-20.htm)
Title: Re: Finally started documenting my current robot.
Post by: amando96 on April 16, 2010, 12:17:44 PM
200 bucks for a chassis!? Crap! That's my whole robot!

haha that's more than double what my current 'bot cost so far, i do a lot of scavenging...

nice looking bot though!
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 16, 2010, 02:32:01 PM
The chassis has proven itself though, a few times now when i am not paying attention, it has driven over curbs, and pulled itself up over them as well. No damage. Handles moderate grass and dirt no problem. The HDPE is real easy to mount things to.

This isn't a robot for you living room.
Title: Re: Finally started documenting my current robot.
Post by: parallax on April 16, 2010, 05:45:57 PM
The chassis has proven itself though, a few times now when i am not paying attention, it has driven over curbs, and pulled itself up over them as well. No damage. Handles moderate grass and dirt no problem. The HDPE is real easy to mount things to.

This isn't a robot for you living room.

The saying "You get what you pay for" definitely applies here! Given what you are trying to do, I would say 200 dollars is a fair price  ;) I won't even go into what I paid for servos for my hex  :-\ It was totally worth it though as I have learned soooo much from my bot! There is something to be said for creating a bot by scavenging for sure. However I feel like you can only go so far that way without some serious computer engineering knowledge, or mechanical engineering knowledge and access to a fully stocked machine shop. Correct me if I am wrong, but I feel like you feel the same, madsci1016.

Thank you for the link! This is an option I will totally look into. When you get your gyros, will you replace your Honeywell entirely with this? Or will you just add gyros?
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 16, 2010, 10:49:50 PM
Just add gyros most likely, as it's cheaper and I'd like to learn how to meld the data together.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 19, 2010, 12:31:06 AM
Here's a better video of the new redesigned interface, and a Picture in picture of SAGAR running the mission.

BE SURE TO WATCH IN HD!!!!

SAGAR Autonomous Rover Waypoint Mission Interface and Vehicle Video (http://www.youtube.com/watch?v=cNZccRC8Zek#ws)
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on April 20, 2010, 08:21:40 AM
I've started a series on how SAGAR works. First installment is the communication protocol to the user GUI. Enjoy

http://www.billporter.info/?p=202 (http://www.billporter.info/?p=202)
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on June 02, 2010, 04:51:06 PM
Latest SAGAR update:

SAGAR can now be driven by PS2 Controller!!!

PlayStation 2 Controller Arduino Library Demonstration (http://www.youtube.com/watch?v=LMgzF7qeeEY#)

This is just first version. Final controller will have 20x4 LCD to give feedback to operator.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on August 07, 2010, 09:52:55 PM
New Update,

New motors and motor controller. Designed a 'Arduino daughter board' for a Pololu motor driver.

More details and info if you want a free PCB of the daughter board at: http://www.billporter.info/?p=286 (http://www.billporter.info/?p=286)

(http://www.billporter.info/wp-content/uploads//2010/08/IMG_2967-Medium.jpg)

(http://www.billporter.info/wp-content/uploads//2010/08/IMG_2968-Medium.jpg)
Title: Re: Finally started documenting my current robot.
Post by: Ro-Bot-X on August 08, 2010, 06:07:32 AM
Nice motors Mad, how big is the backlash on them? I placed an "order" for a PCB on your site...
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on August 08, 2010, 09:06:12 AM
They definitely have some backlash. I did some tests of going full speed and then braking hard, and it nearly jumped off the table.
Title: Re: Finally started documenting my current robot.
Post by: madsci1016 on August 08, 2010, 05:01:02 PM
More pictures:

The old board, man it looks messy now:
(http://www.billporter.info/wp-content/uploads//2010/08/IMG_2969-Medium.jpg)

With the power sensor:
(http://www.billporter.info/wp-content/uploads//2010/08/IMG_2971-Medium.jpg)

Installed. Man it looks sexy.
(http://www.billporter.info/wp-content/uploads//2010/08/IMG_2973-Medium.jpg)