Kite Tests on Land and Water

G12 & G13 test – Aug 10

8/10/11

Don and Dudu took the G12 and G13 rokkakus with the new taped construction to Crown Beach for another test. They used a telephoto camera mount to take video with a GoPro from one of the lines and from the ground and put Joe’s superlight mount on the back of one of the kites.

Rok G12 & G13 test – Aug 5

8/5/11

At Crown Beach. Don flew both the G12 and G13 design rokkaku kites with the new taped construction. He used a half of a plastic toy world globe and a 55mm UV lens filter to create a protective camera housing.

ROK G13 test – Aug 4

8/4/11

Test:
-Weight: 575 g
-Seam construction used 50mm cover tape inside out
-Bladder 2mil
-Wind: 10-20 knots
-Crown Beach

Conclusions:
-Wind was too gusty for this size, which is 3.4m
-Flutter on one side of bottom edge
-Bridle points need to be non-floating, for fast inflation
-Strut ends also need to be non-floating

Rok G12 – fully taped construction – test Aug 3

8/3/11

This was the first test of the new construction, which includes cubic 50mm tape inside and out and 25mm double-sided tape.

We inflated the kite to 5psi. We tested over 2.5 hours at Crown Beach, in 10-knot winds. The flight was stable, with a line angle at 45-50 degrees. We taped a GoPro to the line and used a 100m 1.6mm line.

Betsy note: bottom photos show the G12 kite seams in the shop prior to the test.

Lifting Kite AoA Actuator

6/8/11

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. […more]

AoA adjuster test with G9 rokkaku

6/2/11

We flew the G9 rokkaku kite at the runway, and again at the parking lot outside the shop, to test the angle of attack adjuster that Don and Jamie have been working on. The adjuster operates by changing the length of the back lines. While flying, the front lines take most of the load–the back lines take only about 25%. Shortening the back lines changes the angle of attack so that there is less load on the flying lines, which is helpful for reducing the force on a winch when reeling in the kite. Meanwhile, lengthening the back lines would change the angle of attack to project more kite area and increase the kite’s power, in order to lift a […more]

G11 rokkaku kite test

6/2/11

Flew the G11 rokkaku kite on the runway today. The G11 kite has the same strut-spar connection design as the G9 and G10 kites, but the G11 is 25% smaller overall, and its tubes are made of Dacron, not cuben fiber. The kite flew stably but had a tendency to steer in one direction, which is a problem that many of the earlier roks had. We may be able to solve with bridle readjustments, however.