Velomobile start of a new project

Charles wants a Velomobile, a small human powered car, to complete a challenge of cycling round Britain. Charles Barnard is a long distance cyclist, he warmed up by doing Lands End to John O’Groats followed by 4,800 kms round the perimeter of France, then capped that by cycling  864 kms along the Pilgrim’s Way, up and over the Pyranees, to Santiago de Compostela, in Galicia, N.W.Spain. All of these expeditions have three things in common, weather, wind and sun. Singly and in combination these elements can be very wearying, to the point of psychological collapse. The answer, Charles decided, is a Velomobile. The shelter will keep you dry and the aerodynamics will reduce the effort required. If the reduction is only 10%,  it is cumulative, day to day, and then over 100 days cycling results in a saving of 10 days in simple terms. That is a lot.

 

CHARLES TRIKE LAYOUT 1
CHARLES TRIKE LAYOUT 2
CHARLES TRIKE LAYOUT 3
I was introduced to Charles through Walter Galbraith and the Outdoor Group, a walking and cycling club. I told him about my experience building recumbent bikes and aerodynamic Super Mileage cars. and I offered to design and build a body for his recumbent trike. I took initial measurements of his trike for clearance dimensions. The next day I sent Charles a couple of photos of my cars and also one of the construction details.of the Blimp. Nothing really happened for about a couple of months as Charles was, and is, tied up in a property refurbishment in the South. I prepared five 2D sketches laying out options and body plans, open and closed. One of the main topics of discussion had been that I thought Carbon Reinforced Plastic was difficult and messy to prepare, expensive, and worst of all, heavy. I’ll post on this later.
CHARLES TRIKE LAYOUT 4
CHARLES TRIKE LAYOUT 5
All this discussion sbout Velomobiles, got me thinking about building my own for some long distance touring. I resurected a drive system I designed many years ago but never got round to building. It is a Linear Drive which reduces the frontal area of the feet when pedaling. The design for this trike and Charles’ trike body are all based on the principles of using ellipses to generate volumes from one calculted profile to another. I worked up an illustration version to show the difference between that and a plain profile plot. The upper and lower body profiles are NACA 0008. The equator is NACA 16-021. The head faring is also NACA 16-021. All of the plotting co-ordinates are manipulated in an Excel spreadsheet.
CYCLECAR TRIKE LINEAR DRIVE 16021

CYCLECAR TRIKE LINEAR DRIVE 16021 ILLUSThe outcome of our next meeting was although Charles appreciated the 5 examples what he really wanted was my illustration version. I explained he had been seduced by a prettier picture and it is really unwise to set off on a trek round Britain in a untried trike. So I incorporated some of the shape ideas into one of the 5 and set to work building a 3D drawing in Sketchup, which I had only just started using.

 

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