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[cuppa]

Forgive me for being such a duffer but I am thinking about using a twin motor/esc and shaft setup for the first time and was wondering how to control both motors most effectively.


I am not sure if the best way is to use channel 3 for the port motor and channel 2 for the starboard or to use channels 1 and 3 and an electronic mixer?


many thanks for any advice.

[radiojoe]

Personally I would use a mixer, to keep forward and astern on one stick and let rudder and mixer take care of each motors speed on turning, I have tried a motor on each stick but found it difficult to control the stbrd motors speed and rudder at the same time, the only advantage of a motor on each stick is you can have one forward and one astern, but that's just IMHO. Joe

[boatmadman]

Acton do a twin motor esc and mixer in one small box. Brilliant bit of kit.
Think it is the P94 and is sold by component shop


I have one in my AHT and it operates spot on


Ian

[Colin Bishop]

Check out Dave Milbourn's article on the Model Boats website - should answer most, if not all your questions.

http://www.modelboats.co.uk/news/article/but-i-don-t-understand-electronics/18054

Colin

[NFMike]

I am not sure if the best way is to use channel 3 for the port motor and channel 2 for the starboard or to use channels 1 and 3 and an electronic mixer?

It depends what the boat is and how you will use it. Probably one of these three:
Long and thin and mostly just driving it around the lake at half ahead - just run the motors as one.
Squat tug that you want to use for towing and manoeuvring - tank steering.
Somewhere in the middle - throttle/rudder mixer.

[cuppa]

Thanks chaps


Your advice is much appreciated. Based on the advice given I have decided to use 'tank steering' and mix channels 1 and 2. It is for a small tug.


Many thanks for your help.

[inertia]

http://www.action-electronics.co.uk/pdfs/Twins%20Ver2.pdf
Have a read of this before you finally make up your mind. It might help. Plague is right but tank steering takes a lot of learning and practice to get right. P94 Lite would be my recommendation for a small tug (BTW you can switch it to either mixing or tank steering modes anyway!).
Dave M

[Colin Bishop]

As Dave says, tank steering is best used with tanks as they don't drift around as boats do which makes precise steering a bit hit and miss unless you are simply doing a bit of manoeuvring in a dock for example.

Colin

[cuppa]

Thanks chaps


Your advice is much appreciated.

[cuppa]

Have been playing with the transmitter's mixing today and think I have it sorted. I now have ahead/astern on channel 2 and motor speed differential on channel 1 using the transmitter's elevon mix. I have also created a user defined mix that mixes channel 4 (rudder servo) with channel 1 with channel 1 as the master so the rudder servo is effectively controlled by channel 1.


So basically speed controls plugged into channels 1 and 2 and steering servo plugged into channel 4, a little mixing magic and it appears to do what i need it to.

[inertia]

Just make doubly sure that the rudder doesn't work against the motors when going astern (ask me how I know...........) 
DM