Potential motor controller for RC ships

[William]

I saw this on the back cover of Nuts and Volts magazine
and looked up the web site.
http://www.parallax.com/detail.asp?product_id=29144

It's primary intent is as a robot motor controller interfaced to
a small microcontroller like this company's Basic Stamp.
However, the interface is compatible with traditional RC
servo signals. (It won't load the RC system's battery,
since it has its own regulator driven from the motor battery.)
The price is right too.

-Wm

[John Mianowski]

On Wed, 08 Feb 2006 05:52:12 GMT, "William"
<all_replies@news.group.please> wrote:

>I saw this on the back cover of Nuts and Volts magazine
>and looked up the web site.
>http://www.parallax.com/detail.asp?product_id=29144
>
>It's primary intent is as a robot motor controller interfaced to
>a small microcontroller like this company's Basic Stamp.
>However, the interface is compatible with traditional RC
>servo signals. (It won't load the RC system's battery,
>since it has its own regulator driven from the motor battery.)
>The price is right too.
>
>-Wm
>

I don't understand what features might be useful in R/C ships. For
about the same $$ I can get a MTronics or ProBoat ESC that's
waterproof (which IS a useful feature for R/C ships, IMO).

It's an interesting product & clever design, though.

JM

[William]

"John Mianowski" <spamfree@skytex.net> wrote in message
news:l41ku19ks60dj0gseq2kppj11p8oursj8g@4ax.com...
> On Wed, 08 Feb 2006 05:52:12 GMT, "William"
> <all_replies@news.group.please> wrote:
>
> I don't understand what features might be useful in R/C ships. For
> about the same $$ I can get a MTronics or ProBoat ESC that's
> waterproof (which IS a useful feature for R/C ships, IMO).

I've seen at least one report of the ProBoat burning up under what
sounded like a moderate load. Don't know the details so I don't
know if it was a flaw, mismatched motor, or bad air circulation.

Still, looks like a good unit to try. Thanks for the tip. I'm curious,
though, does the ProBoat remember the "programming" of the
pulse width while powered down? I don't want to run it rail to rail
each time I turn it on to show it what the range is. \

It was really the single-pulse setting feature on the Parallax unit
that intrigued me - my interest is in adding on-board computer
control as a kind of drive-by-wire. That's simpler if it can set
speed with a single pulse, then concentrate on steering. (I
have visions of putting it on autopilot on a racetrack course like
the old Bismark motorized model.) -Wm

[John Mianowski]

>> On Wed, 08 Feb 2006 05:52:12 GMT, "William"
>> <all_repl...@news.group.please> wrote:
>
>> I don't understand what features might be useful in R/C ships. For
>> about the same $$ I can get a MTronics or ProBoat ESC that's
>> waterproof (which IS a useful feature for R/C ships, IMO).
>
>I've seen at least one report of the ProBoat burning up under what
>sounded like a moderate load. Don't know the details so I don't
>know if it was a flaw, mismatched motor, or bad air circulation.
>

Frankly, I've never used one but have plenty of friends who do use
ProBoat without any troubles reported.

>Still, looks like a good unit to try. Thanks for the tip. I'm curious,
>though, does the ProBoat remember the "programming" of the
>pulse width while powered down? I don't want to run it rail to rail
>each time I turn it on to show it what the range is. \
>

Not a user myself, but others report that it's similar to setting up a
MTronics - it holds its setup unless you press a button when 1st
powering up, or somesuch.

>It was really the single-pulse setting feature on the Parallax unit
>that intrigued me - my interest is in adding on-board computer
>control as a kind of drive-by-wire. That's simpler if it can set
>speed with a single pulse, then concentrate on steering. (I
>have visions of putting it on autopilot on a racetrack course like
>the old Bismark motorized model.) -Wm
>

That's what I thought was interesting, too, but not a typically useful
feature with a standard R/C set. I've got some projects in the hopper
that involve use of a microcontroller (more than 1, actually). Is
navigating a prescribed course what you've got in mind, or is there
anything else?

JM

[William]

"John Mianowski" <spamfree@skytex.net> wrote in message
news:1139545944.462858.52650@z14g2000cwz.googlegro ups.com...
>>> On Wed, 08 Feb 2006 05:52:12 GMT, "William"
>>> <all_repl...@news.group.please> wrote:
>>
>
>>It was really the single-pulse setting feature on the Parallax unit
>>that intrigued me - my interest is in adding on-board computer
>>control as a kind of drive-by-wire. That's simpler if it can set
>>speed with a single pulse, then concentrate on steering. (I
>>have visions of putting it on autopilot on a racetrack course like
>>the old Bismark motorized model.) -Wm
>>
>
> That's what I thought was interesting, too, but not a typically useful
> feature with a standard R/C set. I've got some projects in the hopper
> that involve use of a microcontroller (more than 1, actually). Is
> navigating a prescribed course what you've got in mind, or is there
> anything else?

A number of things - some of which are probably outside my budget
(yeah, GPS navigation would be nice :-)

I thought it would be nice to have some "canned" programs that could
be invoked. Initially I was just thinking of animations (like the operation
of the main battery in a realistic manner) that could be triggered by
pushing a stick to one extreme or another (two or more events per
channel). Maybe a fail-safe in the event of signal loss or detection and
signaling of failures, etc.

Most of the "lakes" around here are rivers, so if the signal is lost, having
it go into a circle would improve the chances of it not ending up in the
Gulf of Mexico (and maybe restore the signal if it's a range issue).

Adding a simple digital compass module might give it some rudimentary
dead-reckoning ability. At least it could reverse course.

-Wm

[John Mianowski]

William wrote:
> A number of things - some of which are probably outside my budget
> (yeah, GPS navigation would be nice :-)
>
> I thought it would be nice to have some "canned" programs that could
> be invoked. Initially I was just thinking of animations (like the operation
> of the main battery in a realistic manner) that could be triggered by
> pushing a stick to one extreme or another (two or more events per
> channel).

Here's a similar example that somebody else has done:

http://wmunderway.8m.com/cont/gfcs/gfcs.html

> Maybe a fail-safe in the event of signal loss or detection and
> signaling of failures, etc.

Those can be bought off-the-shelf.

> Most of the "lakes" around here are rivers, so if the signal is lost, having
> it go into a circle would improve the chances of it not ending up in the
> Gulf of Mexico (and maybe restore the signal if it's a range issue).

Where are you located? My local waters drain into the Gulf as well.

> Adding a simple digital compass module might give it some rudimentary
> dead-reckoning ability. At least it could reverse course.

My interest is in combat. I've designed a system to do true director
fire control, & have built some functional prototypes, although nothing
that's been put into a ship yet.

To extend the concept to what I consider its logical extremes, I'd like
to ultimately build a completely autonomous combat warship that does
the following:

- Sail a prescribed course (basically, a circuit) indefinitely while
avoiding obstacles (some of which may be moving, others stationary).

- Detect other model vessels (targets) on the water.

- Discriminate among targets, as to whether they are friendly, enemy,
or neutral. Further discriminate whether targets should be engaged,
avoided, evaded, or ignored.

- Engage targets by maneuvering into a favorable position.

- Acquire targets by determining range & bearing so that weapons may
be aimed.

- Assign specific shipborne weapons to appropriate targets as
determined by weapons' effective ranges, fields of fire, &
appropriateness to the target. "Weapons" in this context are CO2
cannons & torpedos.

- Launch weapons.

Repeat from Detection until the target is destroyed, ammunition is
depleted below some level, or damage is sustained as determined by
water detectors inside the hull. Resume "cruising" (return to
prescribed course) or return to base, depending on ammunition or damage
status.

The last 3 operations (Acquire, Assign, Launch) are covered by the fire
control system, which also does the maneuvering but under remote
operator control.

JM

> -Wm