As I told you in my last blog, we successfully finished two fully functional Wolferl flight-controller boards for our future UAVPs:

Next we wanted to build two stable and strong frames for our quadrocopters.

We bought several four cornered aluminium poles which we used to build a aluminium cross by milling notches into the middle of the poles so that they fit seemlessly. We then secured them in their place by scews and small aluminium plates which we drilled holes into accordingly.

We built two different frame types, one built from solid aluminium poles and one built from hallow aluminium poles.

The hallow variation has a weight of 232g and looked like this:

The solid cross weights 524g and looks not really different:

As you can see the weight difference is nearly 300g so we decided to use the hallow version for our first try on a frame.

Next we drilled holes for the motor anchorage and mounted the motors:

One of the two UAVPs will use Hacker 20-20L motors with EPP 1045 propellers which will give it a thrust of over 600g per rotor. This will result in a total thrust of over 2.4kg for all four of them. Our expected total weight will be around 1kg so we will have some 1.4kg thrust in reserve:

The second one uses AXI 2217/20 motors and looked like this at that stage:

It's motors will do also around 600g thrust per motor with the same total thrust of 2.4kg:

With mounted EPP 1045 propellers the Hacker version looked like this:

Next we unmounted all motors again and started building some landing gear for the quadcopters:

In the end we went for a simple contuction which will also help absorbing some of the deformation energies of hard landings:

When we combined the frame and the landing gear it finally started to resemble something like a quadcopter:

This will serve as a frame for our future UAVPs.

The next step to completion will be adding all the powerlines and mounting the flight-controller in the middle of the construct.

I will tell you more in my next blog entry!