Calculating Motor Requirements – Update

UPDATE 02-03-2014

Since writing this article eCalc have started to charge for the use of the calculators. Starting from $0.99 for a months access to a single calculator to $11.99 (currently $9.99) for 12 months for all calculators. Is it worth it? For me no, now that I have my quad I no longer need to use it. Only if I upgrade or build a new one will I need to use it. It is a shame that they feel the need to have to charge and I fully understand why they are charging, websites cost money to function. I think more people would buy if it were $1.99 for a years access to a single calculator. If you are a hobbyist how often will you need it? What would you consider a fair price or do you think what they have setup is okay? Comments welcome!

In a previous post I noted that I was waiting for the motors to be sent. Because I am very much like a child in a sweet shop, (I want to fly it now now now!), I started looking at other motor choices.

There is a website (www.ecalc.ch) which has several calculators on it to help you work out theoretical battery flight times. The four calculators are for traditional propeller planes, multicopters, fan ducted planes and traditional helicopters, each offered in 10 different languages.

For this post I will be using the multicopter calculator. To start with I enter in the details that it needs based on the motors I am waiting on (935KV).

Build Progress – Delays

Well the build is almost over, almost. Unfortunately I am waiting on the motors and props. An email from Unmanedtech let me know that there is some problem with the factory not sending them out. Infuriating as I have the machine sitting here almost ready to go.

Build Continuing – APM Mount, GPS, Landing Gear

As I continue to build my Quad’ I have had to solve a few issues. After reading on the ArudPilot website about the compass (and GPS) module, I needed to mount it away from sources of interference; the ESC and motors. As both can output a magnetic field it seems. Again I turned to my trusty 3D printer to produce a design I made to mount the GPS and compass module on a mast. This sits about 100mm above the top of the frame, which is about as far as I can go with the length of its cables.

Build Started – 3D Printing to the Rescue

The build has started! My parcel of parts turned up on Friday (most of them anyway, still awaiting the motors and props – more on that later). I got home all ready and excited to start my build and just as I finish making the obligatory cup of tea (I am British after all!), the power failed.

Parts Ordering Started

Okay, I have completely thrown out my plans! I have currently ordered the motors, props, ESC, APM (inc GPS/compass) and frame from Unmannedtech.co.uk. They have been really helpful so far, having put the items on reserve for me while the motors and props come back into stock – hopefully in about 2 weeks or so.

The Plan

Unfortunately I do not have the funds to get all the parts to build a quadcopter in one go. As I am too impatient to save up to do that as well I plan to buy a few parts each month. My current plan is as follows: