ESP8266 Community Forum

- Thu Jun 18, 2015 5:04 pm #20854 Only 21 days after ordering two "Dual Motor Driver 1A TB6612FNG" arrived today!
After some searching I found them for only 2.70$ (with free shipping to Germany) per pcs on Aliexpress.

The main reason I bought them in addition to L293D I already have is that logic voltage input range is 2.7-5.5V.
That allows to use these pieces directly with ESP8266 3.3V chips, and still being able to drive two 15V motors (@1.2A / 3.2A peak).
So it seems that I can now eliminate the LD33V and Logic Level Converter by replacing L293D with TB6612FNG in above Fritzing diagram.




Hermann.

- Sun Jun 21, 2015 8:06 am #21095 I had problems with NodeMCU PWM last time.
Today I started easy with Arduino Pro Mini 3.3V running Bitlash controlling 11.77V over TB6612FNG motor controller directly.

These are the bitlash commands to make motor running slowly:
d10=1 (enable TB6612FNG)
d12=1 d13=0 (turn left)
a11=30 (run slowly)

a11=255 gets very loud and vibrating

I did this after a11=30, from what I see this command should better not be done at higher speed
d12=d13 d13=!d13

Works totally reliably although I have not added any capacitors right now.
Did compile "billroy-bitlash-7d80a37/bitlashdemo/bitlashdemo.pde" for 38400 instead of 57600 in order to run it via minicom.

Next step -- use ESP8266-01 instead of Arduino.


Hermann.

- Sun Jun 21, 2015 11:24 am #21110 I give up for the moment with ESP8266-01 and motor cotrol.

I got wireless motor control working via ESP8266-01, telnet into Bitlash command shell on Arduino Pro Mini, controlling 11.77V over TB6612FNG motor controller:


But whenever I reached PWM 100 ESP8266-01 got reset.
I did add 10uF capacitors at the motor as well between VCC and GND of ESP8266-01, no change.

For motor test station control must be reliable, especially for high speed.
ESP8266-01 does not give that right now.

Will have to go with programs on Arduino that gradually increase the speed limit and stop after preprogrammed time. Without ESP8266-01 bitlash control was 100% reliable even around PWM=255. So no interaction with MTS for now (which is no real problem since MTS is only for determining which motors to use for autonomous robot):


Hermann.

- Fri Jun 26, 2015 7:16 am #21748 Did my Motor Test Station project without wireless until today, see:
http://forum.arduino.cc/index.php?topic=331722.0

The fastest I got with 12V motor was 6.90m/s(!) or 24.84km/h.

Today I made my ESP8266-01 with Lua telnet server allowing to telnet into ESP8266-01 a passenger of the last setup:


No wire connection, no resets seen as those discussed before in this thread.
There was an accident at speed of 17.6km/h and the ESP8266-01 got thrown out and ended up at security glass.
And it still did work(!), telnet session was alive, no reset happend:



youtube video:
https://www.youtube.com/watch?v=nSRXG5Cs9UA&feature=youtu.be

and here you can see ESP kicked out at quarter video speed:
http://rowvid.com/?v=nSRXG5Cs9UA&t=18.5&s=0.25


Copying in youtube text for completeness:

Same setup as in (9), but with an ESP8266-01 as passenger.

Did telnet wirelessly into Lua shell via the ESP8266-01 telnet server.

Time output (in sec) before and after the run:
＞ print(tmr.time())
135
＞print(tmr.time())
188
＞

This proves that no reset happened, although the ESP's seatbelts did not avoid getting thrown out and being stopped only by security glas. The telnet session survived this accident !!

rowvid.com single frame analysis shows that accident happend at 4.9m/s or 17.6km/h.

I read about an "ESP throwie" before, would not have thought of a high speed throwie


Hermann.