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Archive for February, 2014
Posted by mike_kelly | Feb 20, 2014 @ 12:35 PM | 7,099 Views
Brand new out of the bag.
Posted by mike_kelly | Feb 17, 2014 @ 09:21 AM | 11,072 Views
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* Note: This article is based on an older version of eCalc and there are new features available.
* The free version of eCalc does not make available all the motors in the eCalc database, some will be greyed out until you buy a basic subscription for a few dollars.
* Most of the motor database information comes direct from manufacturers and some exaggerate or just plain don't tell the truth about their products.
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In the first tutorial we discussed using eCalc to get some basic answers
about a multirotor design. How long will it fly and can I lift that
camera and gimbal I want to use?

But eCalc can tell you much more. Let's talk about the limits and
warnings when looking at eCalc results. The mistake I made when I first
started using eCalc was to think the warnings were something I had to
stay way away from. I wanted to make sure I did not come close to those
warning limits in a design. But Markus pointed out that you want to use
your motor fully. You don't want such a powerful, and heavy, motor that
you never really use the full capacity. If you are selecting a 480 watt
motor, but the eCalc results show that, for the combination of parts you are
using, the maximum electrical power the motor is using is
only 150 watts, you are not using much of the potential of the motor. It
means that even at...Continue Reading
Posted by mike_kelly | Feb 09, 2014 @ 10:26 PM | 41,176 Views
What is eCalc anyway? It is a web-based program to take multirotor design data and calculate some valuable information about the design. It was written by Markus Mueller.

eCalc is a powerful tool to answer questions like "will that motor work" or "what will my flight time be"? You can use it as a "what if tool" to design your multirotor. For example, what if I change the props from 13x4 slow-fly to 14x5.5 E props?

Although DJI, for one company, has introduced some very popular ready-to-fly multirotors, many other brands are still custom built by forum members from parts and most are very different builds from each other.

So, let's design a multirotor from scratch. We want to lift a Sony Nex5n camera.
The first thing to realize is that we need to know the weight of every part of this project. When you ask forum members "will this motor be good for me?" it is really hard to answer because you have to enter all the data into eCalc to find out. Unless somebody runs that exact set of parts in their own multi-rotor you probably won't get an answer - because other members honestly don't know.

So, let's start with a Tarot FY690 frame. A frame that can handle the wieght of the Sony Nex5N camera. There are, of course, lots of other frames that will work just as well. I'll also pick out a complete set of parts, somewhat arbitrarily, and then we can play with substitutions to see if we can improve our design.
Frame
1-Tarot TL68C01 (...Continue Reading