New Kit Piece Suggestion

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Tiodargy
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During the feedback session today, I was thinking about a new piece that could be incorporated in next year's kit. A choice that many people experience, but don't really notice is which type of servo to use. The micro servos are smaller, lighter, and less powerful than the regular ones, but then again still take up one servo port. Why even use the micro servos when you can use a slightly larger one with more accuracy?

The new piece that I was thinking about could be a little servo port plug-in (on the BOB) that acts kind of like a USB port hub. This new piece could allow you to plug two micro servos in parallel so that they would only take up one port. The only downside to this idea is that both servos would only be able to be used simultaneously.

Unfortunately, this design won't work for larger servos without a modification to the CBC. The large Tower-Pros that come with the kit consume too much power (then again, I haven't researched the power ratings for the CBC and the servo.) to be used in parallel. The reason I suggested the micro servos was because they consume much less power, and will work in parallel.

For those of you who do not know what a parallel circuit it, a great description of what it is can be found here.

I hope to see this new piece integrated in the kit soon!

-mourginakis

-Tiodargy

Beta
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Title: The Magnificent
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I'm not sure if it is technically feasible to do that. Even if you could put them in parallel, there is no way you could send them separate PWM signals. You'd have to have a controller on the other side of the connection that could decode the interlaced signals, and I'm not sure if our hardware or software was designed to do this, nor do I think it is worth the required cost and effort.

There are already really good alternatives that could be used with the CBC or the next gen controller, such as a USB servo controller. Since we are running embedded linux on both devices, interfacing with USB controllers should be trivial. You could also use the serial port normally used with the Create to talk to a servo controller.

Braden McDorman

Developer of the KIPR Link, KISS IDE, KIPR's 2D Simulator, and CBCJVM.

Reach me at bmcdorman(cat)kipr(dog)org where (cat)=@ and (dog)=. if you need assistance of any kind.

Tiodargy
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Beta,

I'm not sure if you know what I meant, but I didn't mean to control the servos separately. If you were to send different PWM signals to both servos, yes, that would require some kind of decoder on the other end; however, I was meaning to send them both the same PWM signals. It is possible to do so, people have put Y-harnesses on their RC planes to control the ailerons and such.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LX0954&P=0

Above is a typical Y-Harness. I could be wrong, but I'm pretty sure it would be possible to control two micro servos simultaneously with this piece, in synchronization, of course.

-Tiodargy

Beta
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Title: The Magnificent
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I see. That makes a lot more sense. As soon as you mentioned a USB hub I assumed you were attempting to send them different signals. That seems to have interesting use cases.

Braden McDorman

Developer of the KIPR Link, KISS IDE, KIPR's 2D Simulator, and CBCJVM.

Reach me at bmcdorman(cat)kipr(dog)org where (cat)=@ and (dog)=. if you need assistance of any kind.

Tiodargy
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Sorry for not being that clear.

I was using the USB port hub as an analogy for those who might not understand how parallel circuits work. In layman's terms, they both seem like they would be quite similar.

-Tiodargy