Build Instructions

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• 1

  Read up

  First off, before building, make sure you have a good clear understanding of what you want to build.

  The scale and complexity of a kite turbine project is a large undertaking for a home project.

  Check the files section and read the  - sub 1kW Kite Turbine Parts Description document to get a clearer idea of what you could build.

  I don't recommend going straight to the scale of 1kW - That in itself can be a dangerously powerful kite machine.

  Please feel free to adapt this. However- 

  This project is CC-BY-SA-4.0 as long as you keep it under 1kW.

  None of this work is for Kite Turbines in excess of 1kW 

  We will be attempting automated control of larger Kite turbines at W&I only when we remove all human operations from the field of work. 

  Thank You for reading that warning list so carefully

• 2

  Lift kite

  Let's start at the top with the lift kite

  An HQ KAP foil lift kite is a good steady lifter ... not so strong pulling as a single skin but stable.

  Practice with these so you are comfortable with their use before you attach one to a turbine.

  Make sure it is pulling >10kg on the line before you attach it to the lift line bearing at the top of the turbine. You are likely to a couple sizes from 3 to 6m. 

  Here's how they handle in extreme turbulence with a variety of bridle, tether and tail modifications

  Making a controller for these lift kites is easy enough with radio control and a servo pulling the B2 steering lines  ... This will allow you to pull the turbine to the side and stall it without using a backline.

  Adding an arduino and an IMU is bonus - Some simple proportional code https://github.com/rodread/lift-kite-controller

  Here's a description of how that went on the AWES forum

  https://forum.awesystems.info/t/building-a-rc-pilot-kite/524/18
  

  I used to use 3 lines on the lift kite. The main tether to the turbine head and 2 steering lines to downwind anchors. This however does not let you weathercock the whole set so only do this if your wind is always in a steady direction 

  Some old Daisy Kite turbine launching videos
• 3

  Making Kite Turbines 2 different ways

  Now for the turbine

  First up is the older Ram Air Kite Turbine Way

  I published the detail for that on Hackaday a few years back https://hackaday.io/project/159049-portable-kite-turbines/log/149130-oh-yeah-the-kites   Gave that hack a big update yesterday

  This is how the turbine for the scouts went together

  Right now for the 2nd version using rigid blades  

  ...  This makes a much faster and more efficient turbine

  A single rotor element now looks ~like this

  A NACA4412 foil cut from foam, built like a model airplane wing, at 20cm cord ~1m span. Made from 2 parts 1 at 70cm span and one at 30cm pan. The 2 spans are covered in shrink film. The 2 spans plug into the fuselage.  

  The fuselage joins the blade to the main ring compression cuff. (a tube of dacron tape 340cm long with a web strap at one end and a web strap clamp at the other) 

  2x 170cm carbon rods go in the main ring compression cuff (forward of the wing) 

  4 bridles hold the blade to the main tether. Bridles bank the blade with outer tip slightly pointed down (This directs lift away from the axis and helps rotor expansion against torsion.. Helps for stacking rotors.)

  An stl of the fuselage is in the github links https://github.com/rodread/DaisyKiteTurbineControl (often appears 10x too small on 3d print slicing software - comes from rhino working in mm not cm) 

  The 70cm and 30cm span blades are hot wire cut foam, with shrink bonded tape covering. Then plugged into the fuselage cuffs. Then duct taped to the cuffs. 

  The shrink wrapped blades are slotted into the cuffs of this fuselage .

  The spars tubes run through inside the blades and through the fuselage the whole length of the span. The bridles tie around the spars.

  A line looped through both of the spar tubes holds them into the foam, preventing them from being flung out by centrifuge. (That has happened. Do avoid throwing spears around your field)

  There's 4 wee spreaders (made from ~2cm lengths of rod) to stop the bridles cutting into the wing and spars. A loop on the bridles goes over these bars. The bridles all come out on the other side and tie onto the main tether. Best to set the bridle lengths so that the blades outer tips are closer tot the ground than the inner tips. Helps with aerodynamics and dynamic ring expansion.   

  Put 2 of the 170cm rods in the sleeve, attach the sleeve to the next sleeve, repeat until you have (6 in this case) in a rotor.

  Here is a dimensioning guide for Kite Turbines
  

  For your blade tethers, tension them all with the same weight and mark them to make sure they're all the same length with a figure 8 on the bight tied in the end ready to connect to the tether at the top end of the transmission.  

  Figure 8 on a bight is easy to turn into a larks head knot to connect over another figure 8 on a bight.

  Super simple way to make the system modular. so you can attach new transmission or elements as you like.

  For our next set of wings I'm leaning toward ...a mix of cut/print wing rib with foam inserts, a printed fuselage as before, all slotting on together with carbon spars, tied through and end capped ... and also I think a vacuum carbon epoxy skin might work nicely. If you make wings... please get in touch.

  Also for getting more blade performance data to the generation control . I've re-worked the amazing D-Rhem VTOL flight controller to get rotational position dat from the rotors with an ESP32 and MPU9250 https://github.com/rodread/dRehmFlight/tree/master/Versions/dRehmKITE_rod_ESP_wifi-mpu9250SPI

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