Velomobile development drawings: Part 2

The next step was to measure the dimensions of the body I am aiming to transport.
I set up a board as seat back and surrounded myself with boxes for the rib cage/hips, shoulders, back of the head, eye line, leg bent and straight for knee height.
The bent knee height sets the velomobile body height which sets the eye line.

I then drew these up as Chassis Bounded Volume. It is NOT a chassis it is only the volumes and boundaries of a human body cycling lying down.
The light blue plane is the flat foot length.
The top edge of the green plane is the knee height and relative distance.
The dark red plane is the back of the shoulders and head The purple plane is the eye line height and distance of the eyes from the back of the head.
The yellow plane is Eppler 214 scaled to clearance fit at the shoulders at the dark red plane.

I then place a station at the red plane with 16 points where 8 X Eppler 214 profiles would pass for minimum clearance.
There is clearance below the Chassis Bounded Volume for sag in the hammock and the 150 mm (6 inch) ground clearance.
A 26 inch 559 rear wheel and the 20 inch 406 wheels, spats and inboard axle, were placed approximately in the right area.

An Eppler 817 hydrofoil profile was chosen because it is designed to work at low flow speeds and is rear loaded, that is its maximum height is well back on the chord line. This was scaled in the vertical plane, only to give a taut profile line to the nose of the body.

As with the front wheel spats the E214 were then laid on the profile line and then scaled to pass through the station. Whatever shape was generated would be exactly right, but I had no idea what it would look like! I thought the nose profile was irrelevant because the E214’s are stacked with no distortions between levels, aah, well, maybe.

 

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