Author Topic: Transmitter/Receiver issues  (Read 2358 times)

Bericson1989

  • Roboteer
  • *
  • Posts: 9
    • View Profile
Transmitter/Receiver issues
« on: July 21, 2016, 10:45:33 pm »
Lately I've noticed once in a while, my robot will stop receiving commands from my controller, and will just do the last command it received, whether it was stop, spin, reverse, etc.  I've watched alot of Youtube videos where it seems alot of robots lose due to the same thing happening. 

So I'm wondering, is this common to see?  What can one do to lessen/prevent these instances?  Is it mostly a receiver quality issue and can be solved by getting a better?  Is it possibly I'm not supplying enough/supplying too much power?  Any advice on this in general?

Coboxite

  • Roboteer
  • ***
  • Posts: 101
  • Made with real lemons
    • View Profile
Re: Transmitter/Receiver issues
« Reply #1 on: July 21, 2016, 10:52:52 pm »
Need a lot more information. We need to know what parts you're running, what radio you're running, what receiver you're running, what ESCs you're running, and what motors you're running.

From the very bare amount of information, it sounds like you might have a BEC(Battery Eliminator Circuit) conflict. Test it with one ESC plugged into the receiver and see if the control is fixed. If it is, you definitely have an BEC conflict.

Bericson1989

  • Roboteer
  • *
  • Posts: 9
    • View Profile
Re: Transmitter/Receiver issues
« Reply #2 on: July 22, 2016, 10:23:41 am »
Ah, my apologies.  I didn't realize this might be a compatibility issue between/among different components.

ESC = Sabertooth 2X12  https://www.dimensionengineering.com/products/sabertooth2x12rc

Motors = COPAL 60:1 Gearmotor http://www.robotmarketplace.com/products/0-COPAL60.html

Servos for weapon = http://www.robotshop.com/en/hitec-hs-5645mg-servo.html

Battery = Turnigy 1000mAh 2S 20C Lipo Pack http://www.hobbyking.com/hobbyking/store/__9170__Turnigy_1000mAh_2S_20C_Lipo_Pack.html

Transmitter/Receiver = Hitec Optic 5 2.4GHz Transmitter, Minima 6 Micro Receiver http://www.robotmarketplace.com/products/0-HRCJ5800.html

On the BEC note.  The ESC has a built in BEC, so I'm not really sure if I can do anything about a possible conflict other than to use a different ESC, can I?

Coboxite

  • Roboteer
  • ***
  • Posts: 101
  • Made with real lemons
    • View Profile
Re: Transmitter/Receiver issues
« Reply #3 on: July 22, 2016, 02:10:15 pm »
Now I see the issue, your servo is pulling more current than the BEC in your speed controller can provide. Cut and strip the middle wire on the servo's PWM cable(around the PWM connector) and put the stripped wire onto the B+ terminal on your sabertooth controller. This will allow the servo to take current directly from the battery, giving it full power while also not overloading the small BEC circuit. As long as the servo is plugged into the receiver, it will form the full circuit and the servo should work.

Jeff Gier

  • Roboteer
  • **
  • Posts: 76
    • View Profile
Re: Transmitter/Receiver issues
« Reply #4 on: July 22, 2016, 02:23:11 pm »
I've seen this exact problem when using the same sabertooth esc.  Soon enough, your esc will probably die completely. 

Bericson1989

  • Roboteer
  • *
  • Posts: 9
    • View Profile
Re: Transmitter/Receiver issues
« Reply #5 on: July 22, 2016, 02:54:11 pm »
Now I see the issue, your servo is pulling more current than the BEC in your speed controller can provide. Cut and strip the middle wire on the servo's PWM cable(around the PWM connector) and put the stripped wire onto the B+ terminal on your sabertooth controller. This will allow the servo to take current directly from the battery, giving it full power while also not overloading the small BEC circuit. As long as the servo is plugged into the receiver, it will form the full circuit and the servo should work.

This sounds like a learning experience. I'm assuming you are saying I should still leave the battery + wire in the b+ slot along with the servo's + wire together correct?  I actually have two servos with a Y connector connecting to my receiver. Is it really okay to have 3 positive wires connecting to that terminal?

@Jeff - Doc, how much longer does he have left to live?

Coboxite

  • Roboteer
  • ***
  • Posts: 101
  • Made with real lemons
    • View Profile
Re: Transmitter/Receiver issues
« Reply #6 on: July 22, 2016, 03:25:40 pm »
Yeah, you're definitely pulling more current than the BEC can handle. Don't worry too much about having three positive wires on the same terminal, your battery can take it.

Jeff Gier

  • Roboteer
  • **
  • Posts: 76
    • View Profile
Re: Transmitter/Receiver issues
« Reply #7 on: July 22, 2016, 05:05:22 pm »
If it is the BEC, then you could be ok.  If not, can't say how long but wouldn't go into combat with it.

Bericson1989

  • Roboteer
  • *
  • Posts: 9
    • View Profile
Re: Transmitter/Receiver issues
« Reply #8 on: July 22, 2016, 08:48:33 pm »
So I seemed to have successfully stripped the wires you mentioned and put them in the + terminal. Not only did I not blow up my bot, it even turned back on, and everything seems to be functioning fully. I've yet to have a transmission drop.

Also, not sure if this makes sense, but my motors and servos seem to be functioning at a higher rpm and torque. Thank you Cobo, I owe you a lemonade. I'll even make it with real lemons.