The first experiment is done in the garden of Demotech's former workshop in Dieren. This experiment was done to gain experience with the WindRotor with a constructive setup similar to a spoked bicycle wheel. It had the below listed special elements:

  • The horizontal axle could not turn with a changing wind direction. This was done as testing regarded only the construction of the WindRotor, and not even its capacity to carry sails
  • The rim was made of light bamboo sticks (12 mm diameter). They were interconnected with clamps that should allow movements in the plane of rotation, but should disallow movements in the direction of the axle of rotation.
  • As spokes on the side where the wind entered, steel wires were used of identical length. They were attached to the hub and the interconnections at the bamboo rim. The wind load would be transferred to the hub by these wires only.
  • As spokes at the side where the wind flowed out, steel wires were used that ended in a tensioner of cord. These wires could be pre-tensioned.
    During rotating under wind load, the rear wires would not take any of the wind load. They would only function to stabilize to rotating rim in position to the axle.

The stiffness of the rim was insufficient, due to the flexibility of the bamboo sticks as well as the poor fixation of the bamboo in the connectors. Pretension on the spokes to create a well lined out and stable wheel did the opposite: the bamboo sticks forced themselves out of the line of the rim.
The construction of this WndRotor seemed attractive as very little material was used. The metal wires could even have been lighter, potentially be made of wire out of car tires. It should have offered little resistance to wind, It would have offered a good base for guidance of the DriveRope.
However, the inherent instability of the construction pointed to the preference of the umbrella-like construction as compared to this bicycle wheel-like set up.

Potential improvements;
Since this experiment was done, much thought had been given to a more stable rim. The bamboo sticks themselves may have been strong enough, the interconnection between these sticks and each set of fore and aft spokes should be far more ridged.

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