Monday, December 26, 2011

Yet more musing on new velomobile

I did a bit more on my mock up to figure out the smallest size I could make it to fit me.

Here you can see the seat angle which is now pretty much about normal for a velomobile.  Well maybe a bit less that normal.   My shoulders just fit under the curved wood strip which is about as low as you can make shell.  I will need to add bumps for my knees and feet.  The nose still needs lots of improvement  which will happen as it develops.  I thought of making a CAD model with the measurements from the mock up but decided against it.  I prefer working with the actual shape as you can see and feel the shape develop and make changes.  Sometimes the shape just doesn't look right so I like to let it sit and just contemplate how to make it right.  A comfortable chair can be a valuable design tool at this stage.  I will build the basic shape and then use some pour foam to further refine shape.  The not so fun part of doing it this way is that making the second side match the first is quite tedious and seems to take forever.  This is where the CAD and CNC model has an advantage.  You just mirror the first side and the CNC machining has them come out exactly the same.  Even when doing this I am always tempted to further refine the shape as the computer model never seems to be exactly what you intended.    Most of the material in the mock up so far is left overs from converting the barn into a workshop. 



A top view where you can see how much the wheels cant in.  It looks pretty skinny so far.  The challenge will be in making the wheel wells so there is an acceptably turning radius and just enough room so I just clear them without touching.  Some careful shaping of the wheel well around where the wheels go when turned should get the clearance I am looking for.  They will end up looking a bit different from what found in current velomobiles.  There is also the possibility of being able to build the velo with different amounts of ground clearance using the same mould.   Not entirely sure if this will work but it is worth a try.  With this idea in mind I have decreased ground clearance to 8-9 cm. 

2 comments:

  1. You could do CAD and still have a tangible (scale) model to look at...
    http://reprap.org/wiki/RepRap
    http://www.makerbot.com/
    http://botmill.com
    http://printin3d.com/

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