Weird Motor Behaviour

Hello Gurus,

I am trying to revive an old RC. My implementation is this

Power 2x3.7 Lipo to Drive the L9110 Motor driver 1x3.7 Lipo to Drive Pro mini & the IC2262/2272 Radio 4 Channel

Hardware RC = http://www.ebay.com.au/itm/281212808317?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 Arduino Nano = http://www.ebay.com.au/itm/111227635175?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 An Old RC - Powered by 4xAA battery L9110 H Bridge Driver = http://www.ebay.com.au/itm/L9110S-H-bridge-Dual-DC-Stepper-Motor-Driver-Controller-Board-for-Arduino-New-/400576054198?pt=AU_B_I_Electrical_Test_Equipment&hash=item5d443183b6

What's weird is that, whenever I put load on the motor it jitters for a few second then starts to pick the speed.

Here's the video of the problem. I will post the schematic soon, it's really simple circuit.

https://www.youtube.com/watch?v=4JeU-j7OpRM&feature=youtu.be

Any help would be very much appreciated.. Cheers!

Something's cutting out on the high current spikes I think - old batteries? Not enough decoupling to 5V supply? Stalling the motor will push the current up, this is triggering the issue.

Multimeter to check the various voltages.

Either that or the carburettor's blocked!

Hi can you post a circuit diagram, either CAD or pic of hand drawn. Will help.. Tom.... :)

Thanks for the inputs, please see attached circuit diagram( pardon me for the handwriting, i tried using frizing but could not find the components that I need)

Hi, have you got the gnd of the motor batteries connected to the gnd of the arduino batteries? If not then the control outputs, 6 7 8 9 will have go current return path, and so any line that is high will use a line that is low to act as current return.

Hope this helps.. Tom.... :)

Thanks for the reply, yes, all the GND are connected. Arduino GND--RX GND--Motor GND are all connected.