Electronic Projects, forums and more.

Go Back   Electronic Circuits Projects Diagrams Free > Electronics Categories > Robotics Chat


Robotics Chat Specific to discussions about robots and the making of.

Reply
 
LinkBack Thread Tools Display Modes
Old 23rd April 2008, 08:40 PM   #16 (permalink)
Experienced Member
 
 
Join Date: Mar 2007
Location: N.B., Canada
Posts: 816
Hank Fletcher is a glorious beacon of lightHank Fletcher is a glorious beacon of lightHank Fletcher is a glorious beacon of lightHank Fletcher is a glorious beacon of light
Default

Quote:
Originally Posted by Torben
0000 Left Stop
0001 Left 1
0010 Left 2
0011 Left 3
0100 Left 4
0101 Left 5
0110 Left 6
0111 Left Reverse
1000 Right Stop
1001 Right 1
1010 Right 2
1011 Right 3
1100 Right 4
1101 Right 5
1110 Right 6
1111 Right Reverse
Ah! So you're saying it would be redundant to have a code for moving both wheels in the same direction. Instead, the cpu program should interpret a keyboard command for "forward" or "backwards" and quickly send alternating left-right code to the robot. Essentially a 50%, alternating PWM signal message sent through the parallel port and over the transmitter would be required for "straight" motion. 100Hz would probably be fast enough, but if part of the system hangs (most suspect would be my Windows 2000 OS), there could be unexpected, chaotic results. I love it!
Hank Fletcher is offline   Reply With Quote
Old 23rd April 2008, 08:51 PM   #17 (permalink)
Experienced Member
 
 
Join Date: Oct 2006
Location: B.C., Canada
Posts: 981
Torben is a glorious beacon of lightTorben is a glorious beacon of lightTorben is a glorious beacon of lightTorben is a glorious beacon of lightTorben is a glorious beacon of light
Default

Quote:
Originally Posted by Hank Fletcher
Ah! So you're saying it would be redundant to have a code for moving both wheels in the same direction. Instead, the cpu program should interpret a keyboard command for "forward" or "backwards" and quickly send alternating left-right code to the robot. Essentially a 50%, alternating PWM signal message sent through the parallel port and over the transmitter would be required for "straight" motion. 100Hz would probably be fast enough, but if part of the system hangs (most suspect would be my Windows 2000 OS), there could be unexpected, chaotic results. I love it!
Actually I was mostly just trying to see what Mike is saying about the limit on the number of discrete values per side. I know Mike's pretty darn smart so I wanted to get what he was getting at and for some reason it didn't sink in for me until this post of yours.

Mike, I know what you're saying now. Makes perfect sense.

Hank, to be honest almost all of my bot programming has been in pseudo-simulators (like droidbattles) so I quite liked your value map, since it would fit nicely with the droidbattles assembly language. Although the possibility of doing the PWM control you outlined would be fun (especially if control were lost as you mentioned.)

I've got some work to attend to then I'll think about this some more.


Torben
Torben is online now   Reply With Quote
Old 23rd April 2008, 11:22 PM   #18 (permalink)
3v0
Moderator
 
Join Date: Jul 2006
Location: USA
Posts: 2,574
3v0 is a name known to all3v0 is a name known to all3v0 is a name known to all3v0 is a name known to all3v0 is a name known to all3v0 is a name known to all
Default

Quote:
Originally Posted by nickelflippr
Seems to be getting a bit convoluted. With one of those cheap Vex controllers that have been talked about, you hold the processing to the receiving end. I am sure that having computer control could have some advantages tho, like maybe not having to recharge transmitter batteries?
Keep in mind that my original suggestion was to get a better RC rig. All I am suggesting is that one could use the original simple RC setup as a channel to send data between two processors. On the reciever end you can use a PIC to decode the data stream. After that standard h-bridge PWM etc for as many items as you need to control.

I have no idea regarding how fast data could be transmitted.
__________________
To control the world from your PC with USB I suggest USB Bit Wacker

3v0's Tutorials for ABSOLUTE BEGINNER
C, PIC 18F, MPLABŪ and MCC18 Compiler
3v0 is online now   Reply With Quote
Old 24th April 2008, 12:06 AM   #19 (permalink)
Experienced Member
 
 
Join Date: Mar 2007
Location: N.B., Canada
Posts: 816
Hank Fletcher is a glorious beacon of lightHank Fletcher is a glorious beacon of lightHank Fletcher is a glorious beacon of lightHank Fletcher is a glorious beacon of light
Default

Quote:
Originally Posted by 3v0
I have no idea regarding how fast data could be transmitted.
There seems to be only one way to find out, and that's to do it! I'm going to have a crack at it, first a simple non-stream method. If that works well and consistently, I might try bumping up my options to - dare I dream - a two-bit packet!

Last edited by Hank Fletcher; 24th April 2008 at 12:52 AM.
Hank Fletcher is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes



Similar Threads
Thread Thread Starter Forum Replies Latest
FC-130: pimping the Tamiya gearbox? Hank Fletcher Robotics Chat 25 15th April 2008 09:24 PM
tamiya gearbox comparison? Hank Fletcher Robotics Chat 12 17th February 2008 03:49 AM
Using Oscilloscopes mechie Electronic Theory 9 29th November 2007 09:49 PM
Tamiya Gearbox bushings. 3v0 Robotics Chat 2 22nd September 2007 10:17 PM
Central Heat and Air Remote Control ae4jm General Electronics Chat 4 6th June 2006 12:08 PM


All times are GMT. The time now is 04:14 AM.


Electronic Circuits  |  Radio Controlled
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.