RoboSavvy Forum

Introducing Big Foot

2007-04-20T16:43:06+01:00

I choose the cartwheels instread of walking for speed and stability. Big Foot tends to wobble quite a bit during walking, and after several steps falls over. Now, I could have modified the default walk (or fast walk) code to improve stability, but, due to time pressure, decieded the path of least resistance was to use cartwheels as the primary means of locomotion.

Has anyone imlemented ZMF or COG on their RN? I would like to put either on mine to improve walking stability and speed.

Keith

Statistics: Posted by kemsulli — Fri Apr 20, 2007 4:43 pm

Introducing Big Foot

2007-04-20T15:30:00+01:00

There's the fast walk template for download. Then RN-1 won't have to do all those 90 degree turns. Just have all the leg and ankle screws fastened down with Loktite or finger nail polish so they don't vibrate out. A faster turn is also suggested which can be accomplished with a wider turn stride.

humanoido

Statistics: Posted by Humanoido — Fri Apr 20, 2007 3:30 pm

Introducing Big Foot

2007-04-20T11:44:53+01:00

This seams like a stupid question but why does it cart wheel every where. Why doesn't it just walk it would surely be faster and easier to program?

I have to say it does look call rolling all over the place.

Have you tried any control methods for it like ZMP or COG.

Bren

Statistics: Posted by Robo1 — Fri Apr 20, 2007 11:44 am

Introducing Big Foot

2007-04-20T05:23:49+01:00

I posted a video to youtube: http://www.youtube.com/watch?v=dKbBnltDHm4. Sorry about the poor quality. It's sort of long since the robot doesn't move overly fast.

Keith

Statistics: Posted by kemsulli — Fri Apr 20, 2007 5:23 am

Introducing Big Foot

2007-04-19T23:24:02+01:00

Thanks for the reply.
Pure genius!

humanoido

Statistics: Posted by Humanoido — Thu Apr 19, 2007 11:24 pm

Introducing Big Foot

2007-04-19T21:51:41+01:00

Humanoido wrote:
Really impressive all the innovative work you did. How can it do cartwheels with that delicate CMUcam board on the top of the head? Also, how did you write routines to communicate back and forth between microcontrollers?

humanoido

I changed the default cartwheel arm position to allow room for the camera. I'll admit, I held my breath the first time! There is enough room for the camera, but I'm having trouble getting right cartwheels to work, although left works fine.

As for communication, a friend and I wrote a Linux driver to handle I2C communication between the Gumstix and Robostix, so now the code can operate on file handles (pointing to say, /dev/robostix). All the gory details of master/slave and send/receive are in the kernel driver. Communication with the MR-C3024 is via standard serial. On the Gumstix, I use standard file I/O, and use ERX and ETX on the MR-C3024. I send a single byte which is then mapped to the appropriate action; a single byte was chosen to reduce latency. Communication between the Gumstix and CMUCam was slightly more difficult since the Robostix only exposes one serial port from the Gumstix. So, I wrote some bridge code for the Robobstix that performs file I/O on the Robstix serial port, and then transfers information on the I2C bus to the Gumstix.

Keith

Statistics: Posted by kemsulli — Thu Apr 19, 2007 9:51 pm

Introducing Big Foot

2007-04-19T21:45:13+01:00

DirtyRoboto wrote:
Are all of the sensors connected to the MR-C3024 or the Robostix ?

Marcus.

The accelerometer is connected to the MR-C3024. The Sharp IRs and the camera are connected to the Robostix.

Keith

Statistics: Posted by kemsulli — Thu Apr 19, 2007 9:45 pm

Introducing Big Foot

2007-04-19T18:41:27+01:00

Are all of the sensors connected to the MR-C3024 or the Robostix ?

Marcus.

Statistics: Posted by DirtyRoboto — Thu Apr 19, 2007 6:41 pm

Introducing Big Foot

2007-04-19T15:11:09+01:00

Bullit wrote:
Wow!, I think this is the most impressive RN-1 I've seen.
Any chance to see some videos?

I'll try to get some videos up in the next few days.

Keith

Statistics: Posted by kemsulli — Thu Apr 19, 2007 3:11 pm

Introducing Big Foot

2007-04-19T12:56:46+01:00

Really impressive all the innovative work you did. How can it do cartwheels with that delicate CMUcam board on the top of the head? Also, how did you write routines to communicate back and forth between microcontrollers?

humanoido

Statistics: Posted by Humanoido — Thu Apr 19, 2007 12:56 pm

Introducing Big Foot

2007-04-19T12:30:08+01:00

Wow!, I think this is the most impressive RN-1 I've seen.
Any chance to see some videos?

Statistics: Posted by Bullit — Thu Apr 19, 2007 12:30 pm

bigfoot

2007-04-19T05:46:57+01:00

wow, I don't think you'll be a newbie for long. It seems like you gotten your RN-1 to do an awful lot in a short amount of time. I'm still working on using the grippers in a routine. great to hear from you.keep it up!!!

Statistics: Posted by engineer — Thu Apr 19, 2007 5:46 am

Introducing Big Foot

2007-04-18T23:47:08+01:00

limor wrote:
locomotion through cartwheels sounds radical and must have been fun to watch. Did you make any particular use of the gyro and accelerometer for the cartwheel locomotion?

Not during the cartwheel; that was simply the default carthwheel from Hitec. After each move completes, the accelerometer is continually checked to determine if Big Foot fell over or not. I'd like to get the gyro working during individual moves to make the more stable. Maybe a summer project.

Keith

Statistics: Posted by kemsulli — Wed Apr 18, 2007 11:47 pm

Introducing Big Foot

2007-04-18T23:45:20+01:00

i-Bot wrote:
mmh tell us more !

remote control of the C-3024 has challenged us all at reasonable speed. Are you using ETX/ERX or making Robobasic code for direct execution ?

What do you want to know? As for remote control, the bot doesn't use any, its fully autonomous.

Keith

Statistics: Posted by kemsulli — Wed Apr 18, 2007 11:45 pm

Introducing Big Foot

2007-04-18T22:46:51+01:00

locomotion through cartwheels sounds radical and must have been fun to watch. Did you make any particular use of the gyro and accelerometer for the cartwheel locomotion?

Statistics: Posted by limor — Wed Apr 18, 2007 10:46 pm