3D Robotics

The more we get into the RC world, the more we're shocked by how overpriced and underpowered a lot of RC equipment is. Most of the specialty electronics, from ESCs to servo amplifiers, are just cheap PIC chips with a few support components. The parts cost a few dollars, but the completed boards often sell for as much as ten times that A good example is the failsafe/multiplexer ("MUX"), which allows you to switch between two inputs for RC control (in our case, that would be RC or autopilot control). The main one on the market is the RxMUX, which costs $79 (shown below).

We thought we could do better. So Jordi created the DIY Drones Failsafe/MUX (shown at the top of the page), which uses the same Attiny45 and multiplexer as ArduPilot. Ours is $16.90, and is literally both one-fifth the size and one-fifth the price as the RxMUX. It also includes all sorts of other goodies, such as recognizing the middle position of a three-position switch and having a programmable signal-loss behavior. Plus it's open source, so you can do anything you want to the code. Our failsafe/MUX is four channels, rather than eight (everyone preferred the smaller one and thought four channels was enough) but if you want an eight channnel one like RxMUX we can make it for you easily for about the same price. Here are the two side-by-side, with a 9V battery for scale.

What else can we take 80% of the cost and size out of?
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  • Old thread, but since Garrick was asking where to get these, Acroname still sell's "Jay's" RxMux. And it is only $19 and still 8 channels.


    8-Channel Servo Multiplexer 2:1 Failsafe (RxMux) | Acroname
    A specialized multiplexer that uses R/C servo signals as a basis for input control and output signals. The RxMux allows control of 8 R/C servos from…
  • Any idea where we can get these anymore?  They're not on the 3DR store since it was updated.

  • You care to elaborate on your baseless claim, or does the cat have your tongue?
  • Egan
    You speak with fork tong
  • Here (U.S.) the Sheriff would need a COA. Not impossible but hard to come by and very limited. Than we have the ACLU knee jerking on privacy. I had suggested to my DOJ contacts that they take the equipment out into the community like they do the K-9s
  • On the deeper question of UAV Legality, I suspect this issue will come down to a question of which event occurs first: 1. a UAV-related catastrophy, or 2. a UAV-related success.
    The General Public would at this moment be reasonable in pointing out a near-zero public benefit for private UAV's with a non-zero risk- (note the same could be said for Dogs.) The question, as I see it, is how does one move the public benefit from zero to non-zero. I suggested helping a small town sheriff get some aerial support. Anyone else have a better idea? Open source is a powerful tool in avoiding regulation, but positive public benefit is certainly another.
  • We could migrate or... we work toward a solution where we live.
  • 3D Robotics
    Patrick, I don't want to be part of an illegal activity. And I have confidence that wise minds (including yours!) will be able to influence the regulatory process so that the reasonable stuff that we're promoting is not made illegal. But if, god forbid, impractical and unrealistic laws are passed, I predict that will be ineffective and widely ignored.

    We will, of course, abide by any relevant laws. But if the laws are nonsensical, we we also avoid being under their jurisdiction, including moving operations abroad if necessary. DIY Drones is an international community--we have participating members everywhere and development will migrate to the most hospitable environments.
  • 8 Channels? JUST BUY TWO!

    Use a servo splitter for the control channel, and Viola - don't over-think this one.

    Maybe you need 12 channels?
  • Even if we are to suppose all of that is true, why do we want to be part of some illegal activity? We as a group have to ask ourselves (globally), do we try and work toward a solution that allows for the sale, development and use of at least some of these products? The point of a hobby is enjoyment, looking over your shoulder detracts from that enjoyment.

    Ignorance of the law rarely washes as an excuse…
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