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GliderPilot suspended in the static test rig

Static test rig. I constructed this cheap and cheerful test rig on our balcony. The center spar of the kite was tied to a rope hung from one of the roof joists. The RCX was slung fore-and-aft on the loops of the kite's bridle. The tiller lines were connected, via the kite's center bridle lines, to the outside wing spars.

You can see that the front portion of the bridle loops has been led forward, over the top of the sail, and taped to the nose of the kite; the rest of the loop hangs free to the rear spreader. The bridle loops were taped this way to get the RCX hanging in about the right position to maintain stable flight.

The kite was made by Tori Tako (a Hawk II, I think). If you're a kite person, you will notice that the front spreader bar was been removed and taped between the two sections of the rear spreader to try and increase the sail area and flatten the wing profile. This modification flattened out the two 'scoops' in the sail profile of the Tako as it is usually set up. The flattening of the sail had two effects: a) improved gliding performance of the kite; b) decreased the kite's stability (made it easier for RCX to initiate turns, but also made the assembly more sensitive to gusts of wind). The inner standoff whiskers were taped to the rear spreader, again to try and keep the wing profile as flat as possible.


GliderPilot harness

The harness. Again, you can see the fore-and-aft orientation of the bridle loops supporting the RCX. Lateral movement of the RCX is controlled by the tiller line -- the two loops in the tiller line are tied to the center bridle lines of the kite with a lark's-head knot. This combination of fixed fore-and-aft suspension with the movable lateral lines connected to the cam made it possible for the RCX to shift its weight smoothly when the cam was turned by the micromotor. The micromotor has plenty of power for performing this operation, and the fact that the motor's turning speed is (relatively) slow probably helped to stop the kite stalling as the weight shifted to initiate the spiral phase of the flight.


GliderPilot, attachment to kite

Attachment of the RCX to the harness. Here you can see the small black rubber bands on the ends of the 1x16 Technic beams. These rubber bands clamp the bridle loops between the inside face of the Technic beam and the triple-length Technic peg. For the first couple of test flights I tied small loops in the main bridle loop; the small loops slid onto the ends of the 1x16 Technic beams and were prevented from slipping off by clicking in the triple-length Technic pegs. However, the knotted-loop-and-peg system was very difficult to adjust (I was going nuts tying and untying knots to reposition the RCX). The rubber band system, OTOH, permits rapid and accurate repositioning.

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