Opinion/Advice: RC Stair Climbing Robot

[elgab]

Hi! I was wondering if I could get your opinion/advice. My team is putting together a stair climbing robot with a motorized retrieval system for our Mechanical Engineering class. We will be using 5 DC brushed motors in total: 4 of these motors (https://www.pololu.com/product/1106) and 1 less powerful motor that we have yet to find yet. We will be controlling these motors using ESCs and a wireless remote control transmitter/receiver system, along with an SLA 12 V battery (https://www.amazon.com/7-2AH-Batter...qid=1538451170&sr=8-14&keywords=12v+batteries). We have already ordered the motors and battery, however we are still deciding on the ESCs and transmitter/receiver system. The stall current for out motors is 5A, although our draw current draw seems to be around 2.5A, based on calculations.

We are considering to use these
ESCs: https://hobbyking.com/en_us/hobbyking-x-car-45a-brushed-car-esc.html - as we need the forward, reverse, and brake functionality. HOWEVER, I think we can't use this ESC because it's input voltage is 6-7.4 V and our battery is 12 V.
Transmitter/receiver: https://hobbyking.com/en_us/turnigy-t6a-v2-afhds-2-4ghz-6ch-transmitter-w-receiver-v2-mode-2.html - as it has a 6 channel receiver (and we need to control 5 motors)

The possible cons are that I think we can't use the mentioned above ESCs because of its input voltage and the transmitter/receiver is says that there is servo reversing but I am not sure if it will work for the motors we have.

Do you think the transmitter/receiver will be able to work together with these motors with the right ESC (ie. will it's reverse function be able to work with our motors)? Or, do you have any suggestions on other products we could use instead (we need to stick to the motors and battery though)? Do you have any suggestions for ESCs?

Thank you!

 

[slowngreen]

I'll bump this for you as I'm curious to see what someone comes up with.

Not sure if any of the channels on that radio other than steering and throttle would be any thing more than on/off channels. You might end up having to go to some Robot RC forums.

 

[cbaker65]

I don't know too much about the robots ,but I never heard of using that many ESC on one rig to drive that many
motors!

Normally on tractor style steering ,you can run two motors on one ESC with reverse ,an micro switches
for steering in which will cut one motor off to turn ,maybe ,not sure!...

I think robots may use a more sophisticated circuitry !

 

[HPIguy]

Yeah, that ESC isn’t going to cut it. You’re going to need an ESC that is 4s lipo capable to handle that voltage. As that battery fully charged will come in around 12.9V. I personally would have went with smaller individual ESCs for each motor involved, and a PDB (power distribution board) similar to how you wire up a multi rotor aircraft. I'm not sure about wiring up five motors to one ESC, as I've never attempted that. That radio should be fine though.