Velux Window Opener

I would like to find a way how short people can open and close this Velux window easily. I was inspired by this https://www.thingiverse.com/thing:2126777 but I found a broken crutch some time ago. And I would like to use the aluminium túbe from this crutch. I took the aluminum tube and designed my opener arround. This tube has an outside diameter of 17 mm. You need six M3 x 25mm screws and one M4 x 35mm screw and the nuts for this screws.