Today we remotely controlled our newest inflated Rok lifting kite’s angle of attack (AoA) using a linear actuator in the kite’s bridle. The actuator was controlled from the ground via bluetooth using an Android phone and tablet. The kite flew with comparable stability and lift to a standard-issue Rok that we used as a control, even after some bridle adjustments to accommodate the new actuator.
We found that the 10cm range of the actuator was enough to make a noticeable difference in the kite’s elevation and line tension, but not enough of an adjustment to explore the full useful range of AoA. In the next test we will use a pulley system to double the effective range of the actuator. We were pleasantly surprised to find that the bluetooth range easily extended from the ground to the kite. Our expectation was that our mobile Android devices would not have sufficient range, and that we would need to put one on the kite, and have it relay WiFi control signals from the ground.
The first picture shows the actuator situated in the bridle line, as seen from a GoPro camera attached to another line. The actuator is fully extended here, having the effect of “sheeting out” the rear bridle lines and decreasing the angle of attack. In this state the kite generates less lift, reducing the line tension and situating the kite lower in the sky.
In the second picture, the actuator is fully retracted, sheeting in the rear bridle by 10cm and increasing the angle of attack.
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