About 3digi

3Digi, what's it all about?

3Digi is an electronic 3-axis stabilisation system for flybarless RC helicopters.

It's not meant to fly the helicopter for you, or rather, it won't return the helicopter to a horizontal attitude for you in a pinch, but it will stabilize a flybarless helicopter's attitude like AC3X or V-Bar or Rondo without any "in-flight assistance".

Such electronic stabilisation systems deliver decisive advantages over the traditional Bell-Hiller (flybar and mixer levers) stabilisation method for the pilot. They enable you to fly almost any model without its flybar-related peculiarities, meaning: the heli just does exactly what the pilot tells it to, without changing attitude unless told to, in any situation. Some examples are - no more having to keep the nose down when speed-flying, consistent roll and yaw rates, perfect tail stability due to "ESP" - the stabiliser knows in advance when the tail load changes (cyclic or collective pitch changes) and pre-corrects drift before it can even happen, unlike traditional gyros. This enables higher and more consistent flight peformance than with a flybar; you can either reach higher speeds in FFF or cyclic acceleration, or you can go for longer flight time with the same performance as with flybar.

A 3-axis stabilisation system sends a command pulse to the swash servos between 50 and 200 times a second (50 Hz is valid for analog servos, digital servos will do at least 100Hz). This serves to show that a stabiliser can react some orders of magnitude more quickly than a human ever could to apply attitude corrections.

So, what makes 3Digi special?

Simply put: it's a freely available design by Dirk Schmidt - this means, you just pay for the cost of the kit and get very detailed build and usage manuals. It's your own reponsibility to assemble the device. This means you get top-rate flight stabilisation for bottom price. Of course, you can also have your own PCBs etched and buy components individually - however, you'll be hard pressed to reach the same price, since we source components in relatively high amounts and can take advantage of volume pricing.

What do I need to assemble the kit?

The electronic components are all SMD parts - this means they aren't soldered through the PCB, but on the surface instead (SMD means surface mount device). This requires special soldering equipment and technique (it's simple to learn!) and most importantly a temperature-controlled soldering station with a fine soldering tip and SMD-solder (ideally containing lead, unleaded solder is very tough to work with!). Another important tool is a proper pair of tweezers, ideally anti-static and ESD safe, a magnifying glass is also useful (one that clips onto a headband and doesn't need a hand to hold it is especially handy). You should also get a small fan and a filter to draw the fumes and smoke generated by soldering, inhaling lead-containing fumes isn't the way to conserve your health.

Obviously, you'll also need the SMD components that you can acquire via a volume order from us or on your own, three MEMS gyro sensors from Melexis and a PCB set you can solder them all onto.