Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: BOREDOM KILLS on April 01, 2008, 06:30:31 PM

Title: Continuous Servo Wiring
Post by: BOREDOM KILLS on April 01, 2008, 06:30:31 PM
     Hello,

My name is Cody, and after 10 years in RC hobby world, I would now like to get into robotics. And to be honest, I feel like I am at square 1 again!  ???

I have found a simple continuous servo chassis: http://www.budgetrobotics.com/shop/?shop=1&cat=51& and I have read that it is possible to wire these servos to a standard 6-channel receiver, which I have as well. I am running into a problem however, on how to wire the continuous servos to run with differentiation steering. NOTE: I am using channels one and two for a pan and tilt camera system, and channel six (i believe) for the battery.
 
If anyone could enlighten me on how to wire continuous servos as robotic motors i would be ever so grateful. I know it is possible (seen it done) and, well, I would really like to hurry and order this kit. Thanks

P.S: diagrams or tips would also be greatly appreciated... thanks ;D

                                                                                                                      -BOREDOM KILLS
Title: Re: Continuous Servo Wiring
Post by: ed1380 on April 01, 2008, 08:29:48 PM
http://www.societyofrobots.com/actuators_modifyservo.shtml
http://www.societyofrobots.com/actuators_servos.shtml
hope this helps
Title: Re: Continuous Servo Wiring
Post by: BOREDOM KILLS on April 01, 2008, 10:08:24 PM
Sorry, I guess my question was a little unclear (I appreciate the help though)

What I need help with is knowing what channels and y harnesses(if needed) to plug the continuous servos in (in a 6-channel GWS receiver). I have tried for hours and cannot figure out how to setup the servos to drive w/ the differentiating steering.

Hopefully this is a little more clear, and someone can help me. :D
Title: Re: Continuous Servo Wiring
Post by: Maltaeron on April 01, 2008, 11:05:33 PM
The servo control wires should plug in directly, the same as for whatever pan/tilt system you have. There is no difference (as far as receiver is concerned) between an unmodified servo and a modified one.

I'm not too experienced myself, so please forgive if I'm not seeing your setup quite right...

Good Luck,  :)
Title: Re: Continuous Servo Wiring
Post by: BOREDOM KILLS on April 02, 2008, 09:58:36 AM
Basically, my question is how is this wired: http://www.societyofrobots.com/images/rcr_soccerrobot.JPG

Specifically, what channels are the servos plugged into (that is my question). I realize that this is a dumb question, but I cannot figure it out. If anyone could tell me whether or not Y harnesses were used, I would appreciate it. Thanks:)
Title: Re: Continuous Servo Wiring
Post by: Trumpkin on April 02, 2008, 10:02:37 AM
suppose you have a reciever with channels 1-4 on it connect drive servos to channels 1 and 2, connect pan and tilt to 3 and 4. connect batteries where it says batteries.
Title: Re: Continuous Servo Wiring
Post by: BOREDOM KILLS on April 02, 2008, 10:24:47 AM
I am running a six channel radio and receiver, and when I plug throttle into 1 and 2, one servo will only work on the y axis, and one servo will only work on the x axis. The same goes for three and four. That is fine for my pan and tilt camera,  but throttle does not seem to work simultaneously, for differentiating steering. That is why I am wondering if a y harness is needed. Once again, sorry I am very new to this.
Title: Re: Continuous Servo Wiring
Post by: ed1380 on April 02, 2008, 04:45:32 PM
find out what channels the joysticks on the remote control. then plug the servos into the appropriate channels on the receiver.

I'm guessing the remote has 2 2-axis joysticks. channel 1 and 2 for one joystick and 3 and 4 for another. then you would use 1 and 3 or 2 and 4 for the diferential drive.

could you post what remote and receiver you have?
Title: Re: Continuous Servo Wiring
Post by: BOREDOM KILLS on April 02, 2008, 07:04:45 PM
the problem that I am having is that I want to run the throttle and such on one joystick, and camera pan/tilt on another... isnt this  possible? Here is a video link of someone who also has a 6-channel receiver, but is controlling the car and pan/tilt on one controller... how does he do this, how does he wire it (Note: I only see 2 plugs plugged in) Also, this is the exact surveillance robot I am going to build. Please walk me through how this is wired:
Title: Re: Continuous Servo Wiring
Post by: Admin on April 06, 2008, 01:50:24 PM
boredom kills, I suspect you are trying to use an aircraft RC transmitter, no? The setup on them isn't designed for differential drive, however it probably has reversing switches on it. Play with the switches until everything does how you like.

Oh, and don't use a Y-harness for controlling servos unless you want the servos synchronized.
Title: Re: Continuous Servo Wiring
Post by: BOREDOM KILLS on April 06, 2008, 02:10:12 PM
Yes, I am using this receiver, but there are no reversing switches on my transmitter: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXKYK1&P=M. If there are no reversing switches, does that mean that I cannot use it? (what if I wired it like the ailerons on a 3d plane, where they go in opposite positions for a barrel role, but the same for elevating? Thank you for your help.

                                                                                                  -BOREDOM KILLS-
Title: Re: Continuous Servo Wiring
Post by: ALZ on April 08, 2008, 02:23:11 AM
Hi: I don't know about RC transmitters but I have started to play around with a "VEX" transmitter and receiver. With their system the transmitter can mix channels also the receiver is feed into a pic chip where it also can mix the channels.  If you know about electronics it's a very good system to play around with and get it to do anything you like. I looked into it because you can get the transmitter and receiver for around $10 on EBAY. You can't beat that!  I am hoping to get it to run DC motors in about 1 month. With the base you want to buy do they tell you what the servo timing is needed for it to run? The VEX timing is .6 ms to 1.4 ms.

Yes, I am using this receiver, but there are no reversing switches on my transmitter: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXKYK1&P=M. If there are no reversing switches, does that mean that I cannot use it? (what if I wired it like the ailerons on a 3d plane, where they go in opposite positions for a barrel role, but the same for elevating? Thank you for your help.

                                                                                                  -BOREDOM KILLS-
Title: Re: Continuous Servo Wiring
Post by: Admin on April 14, 2008, 06:45:52 PM
boredom kills, can you link us to your transmitter?

Just try various combinations on where to plug the servos in. I prefer to use one joystick for the left servo, and another for the right servo. But since you do not have switches, you may have to push reverse to go forward and just suffer :P