R/C Naval Combat

 Ive used a simple PWM speed control circuit (this one below in fact) and found something very interesting.

The batteries last much longer than ever and the speed is 28 (for my HMS Erin) and not 27 or 29 or decided by using different sizes of prop or by using spinners.

The pwm switches on at a certain frequency and off at a certain frequency. thus, the motors speed is regulated. the most interesting thing is that the motor during it's ON phase is at full power, making a speed pre-regulated, which is not without its full power performance.

Due to the moments of being "OFF" there is no usage of the battery and Ive found that 1hour with the motor directly connected used up most of a 7.2AH battery equalled 1hr with a 2.3AH battery using a pwm.

The weight difference is important, but the best thing is the difference in space taken by a battery.

The circuit is simple to make and with 2 500 motors never got hot, even in the french sunshine.

 sure, its about the size of a 2 euro coin.. 2x3 cms

Wow, very interesting. perhaps the next time I order electronics......

 Its true that one has to learn yet another skill, in order to build a speed controller. But... making a battleship that shoots ball bearings (as we do) uses a great number of disciplines and sklills, from cutting and forming wood and plastic and metal, understanding gas movements are just 2 examples.

the parts cost me (here in france) 10€, about 14 dollars (about 700 dollars australian lol)

and the time I took to solder all the bits was half an hour. but any person can build it in an evening.

Ill take some fotos of the back of the board and make a scehatic of ther vero board so it can be even simpler to do.

The circuit says 2 amps max and you're running two 500's, not even hot. Fast gun does draw more amps, direct or gear drive? Mine jumped when I went direct. I look forward to the picts.

I got the 2 amps from the drawing. Right by the motor + and - it says two amps max.

direct drive or gears???

Posted By warspiteIRC on 25 Aug 2009 10:01 AM
If you put it before a MAG speed control, you can control the top speed and let the Mag do the reversing. The pot is set for full speed (for the ship).

Marty

That's brilliant Marty.  I can't believe I didnt think of that with the 50% reverse speed controls I have.  I just might have to throw a MAG into the Belleau Wood!

I love it when the minds meet and talk electronics!!!

Posted By warspiteIRC on 25 Aug 2009 06:25 PM
not necesarily, Wreno. Mag switch with a team delta board (rce220) does not use a servo. ;^}

Marty

True, Marty but you mentioned a MAG switch (which uses a servo as originally designed and usually implemented from what I have seen).  Personally, I have never seen a reversing MAG switch made from a Team Delta.  Is it done?

And using s servo to control the pot is still using a servo.......  Can't do that with a Team Delta (OK you could use a passle of them with resistor bridges to get the effect, I guess).

BTW, as for the reverse, it is important to look at local club rules.  The club I bleong to, NTXBG, does not allow combat reverse.  You can use reverse throttle to stop, or to back off of a grounding, or some other obvious problems (trying to demoss), and in port.  If it is not obvious, you usually announce and see fif there are any objections. 

But, you do not reverse direction in battle to better your position or get out of a tough spot.  Makes you plan a bit further ahead, and makes a lack of situational awareness a bit more fatal.

It is so ingrained in us, in fact, that some have been known to feel funny using reverse and avoid it in the Texas Cage Match, where all the ships are trapped in port for the battle, with little maneuvering room, and reverse is allowed at will.

Some clubs have no such restrictions.