Friday, 3 November 2017

Simplify and add lightness

Colin Chapman's quote "Simplify and add lightness" should be the catch-cry of anyone designing a velomobile or human powered vehicle. One of my favourite designs which has been designed along this mantra is Bob Stuarts Car-Cycle X-4

This is a fine example of integration of parts to make a simpler vehicle. The use of different materials such as fibreglass for the chassis and coroplast for the body is using the correct material for the job. The fibreglass chassis incorporated the hinges for suspension so in fact the chassis IS the suspension. The coroplast body is tough and resilient to bumps and knocks as well as being lightweight.

Another consideration I see in this design is the cost factor with no real "exotic" materials used.
Too often Carbon fiber is seen as a miracle material and used inappropriately or used in a way that does not utilise its specific properties (i.e.. stiffness with low weight). Read about this wonderful vehicle from the link above.

Sunday, 10 September 2017

Full size mock-up of Velomobile chassis

Mockup of velomobile semi-monocoque to test size and entry/exit. Will have to tweak the design a little. Very easy to get into but a little tight around the shoulders. Will revise.

Velocivelo semi-monocoque ©2017

Saturday, 25 March 2017

Practical City Velomobile

I see a need for a velomobile that can integrate well with city traffic. This would mean a higher seat height and room for a child and/or groceries in the back. Again the design must be lightweight and aerodynamic. I really like the Mochet Velocars of the 20's, 30's and 40's . Below is what I see as a possibility.

Length = 2400mm   Width = 1000mm   Height = 1050mm  Weight = 45kg

Wednesday, 22 March 2017

Wheels out velomobile

Here is a render with exposed wheels on Veloci Velomobile. Advantages of this design is the ability of  a tighter turning circle and ease of changing a tyre. I like the look of such velomobiles with the only downside being loss of aerodynamic efficiency (this would be quite small).

Wednesday, 22 February 2017

Elevation of semi-monocoque velomobile

Here is an elevation showing the position and size of the semi-monocoque chassis. Attached to the monocoque will be the rear swingarm, and the front a subframe to locate pedals and front suspension pickups. Again using a semi-monocoque will hopefully make for a lighter velomobile. The semi-monocoque will have to be stiff enough to take loads from the subframes without excessive bending or twisting. I have decided that a good quality plywood would be best for the monocoque for cost for performance.
semi-monocoque velomobile

Saturday, 21 January 2017

Electric assist on velomobiles

After about six months of no progress due to building a new home I have finally got my workshop back and will be starting work on Veloci-velomobile once again.

In this time of limbo I have thought about having electric assist on  a velomobile and came to the conclusion that it would be advantages to have such a system.
Advantages would be...

  • Faster acceleration from standstill and rolling acceleration
  • Easier climbing of hills
From reading reviews of various systems including hub motors, mid-drive and direct drive I believe that a mid-drive system would be best due to the fact it will use the gearing already in the bike. I really like the 8fun system which can be configured with different power outputs to suit regulations. Most common is 250W (Australia & Europe) 300W (New Zealand) and 750W (USA).

Even with 250W the acceleration would be quite impressive and with the aerodynamic advantage of Veloci-velo top speeds would/could  be..

  • 250W = 75 km/hr (46 mph)
  • 300W = 82 km/hr (50 mph)
  • 750W = 120km/hr  (74 mph)
When designing Veloci-velo the design brief was to have a vehicle that could maintain 40km/hr for the average rider so the electric assist needs to be no more than 300W and geared to provide the best acceleration up to the 40 km/hr limit.

See table below...