Cabin eclosure

From Trevipedia

The canopy on the UniSA prototype is a single piece, free-blown from acrylic.

There are several problems with the prototype canopy:

Cleaning

Designing a system for clearing rain and dirt from the canopy is difficult, because of the shape of the canopy and because the acrylic is easily scratched. UniSA students did some promising experiments using compressed air to clear the canopy, but generating enough compressed air might prove difficult.

Construction

The canopy was free-blown from a sheet of aircraft-grade acrylic by Aviation Acrylic Mouldings. This gave good optical clarity, but it took several attempts to get it right. This method restricts the range of shapes that can be achieved.

Hinging

The prototype canopy was hinged from the back because it was easy, but this caused two problems. First, the hinge is too flimsy to stop the long canopy from swaying from side to side. Second, it is almost impossible to get access to the rear parcel compartment. Hinging on the right side might be better, but this will almost certainly block access to ticket machines and drive-through food.

Expansion

The prototype acrylic canopy has a coefficient of expansion significantly greater than the carbon-fibre used to reinforce the edge, and so the canopy changes shape in the heat. This makes it difficult to seal the canopy edge.

Latching

The prototype canopy did not have a robust and reliable latching mechanism. (The latch must be operated from inside and outside the car.)

Opening window

Many people who have seen the canopy have said that they would want an opening window.

Design alternatives

The above are notes of learnings from use of an acrylic canopy. In summary, TREV looks terrific with an acrylic canopy but there are multiple real world problems with this approach. Possible ways forward are:

1. Don't have a canopy. Use TREV pretty much as is with perhaps a small "aero" screen only. This means that weather protection will be non-existent, but no worse than a motor bike. This also means that many aerodynamic advantages are lost. But if TREV's operational performance criteria are set at mostly less than 60km/h and very little greater than 80km/h then the aerodynamic issues can be lessened. A stream of activity that can branch from this approach is to design a soft-top cabin enclosure system. This will still require a robust, wiper and demistered windscreen system.
2. Use the canopy approach but work through viable hinging, cleaning, demisting, opening window solutions.