User:John Bessa/Form Car
This extends my Load-bearing body armor page in that this project attempts to create design criteria creating safety for soldiers involved in defense and peace-keeping activity in a way that is pacifistic. This also attempts to do so in a way that combines benefits; where the LBBA creates a more comfortable pack system for load carrying soldiers, the Form Car attempts to combine twin benefits from its bottom strengthened design criteria: explosion proofing and amphibious capabilities.
The Form Car is design where components form to a framework in a "best of breed" paradigm. The term "car" is appropriate given the term armored car even though it can be characterized as a small truck. Also a famous but now defunct American truck maker was "Auto Car," whose trucks were similar to the familiar old-school Mack Trucks that are still used.
- 1 Design Criteria
- 2 Components
- 3 Sizes
- 4 Lightness and corrosion resistance
- 5 Interchangeability of parts, and ease of repair
- 6 Engine criteria
- 7 Water propulsion
As a military vehicle design paradigm, it seeks to provide reliability, protection, performance, efficiency, and the ability to cross water. It also seeks to provide spin-off designs and components, if not whole vehicles, for the civilian market.
Basic design: components model
- Chassis and engine
- Form, or body, that molds over the engine and chassis component
- Upper half, which includes the top of the vehicle and its interior
Best of breed
Duck and Schwimmvagen
Subaru drive train
The most efficient all-wheel-drive vehicle is the Subaru. Recently I surveyed the deplorable decline of the automobile with a long-time friend and third generation mechanic, and he said "you know, the Subaru is still a pretty good car." Just behind him were two Subaru engines showing their exotic innards.
In short, the form car initially seeks to create a single-frame component to encase an engine, drive-train, and wheel-set, and then lay a duck shaped body over it that is really more on scale with the schwimmvaggen. The engine/drive-train/wheel component should probably be all on the outside of the vehicle as there is no part of this component that cannot get wet, or even be submerged. Only the air supply has to be above water. Insulation if necessary might only have to accommodate extreme cold, as electrical parts are easily waterproofed. A known weak point for these vehicles are the rubber boots that seal mechanical parts that extend from the bottom of the form. In this model, the need for these vulnerable rubber boots is minimized or even eliminated.
Bottom: bombproof, waterproof
Because the bottom of the vehicle is protected from the outside and formed around the mechanical component, it can easily be reinforced for passenger protection of an underside explosion. The design might allow the form to be pushed upward, using gravity to absorb shock, leaving the mechanical component behind, at least momentarily.
The top can be entirely custom, allowing civilian customization, and the point where the top joins the bottom, in fact the entire form shape, are at the whim of particular designers.
Variations in the mechanical component should be based on size, which is traditionally determined by wheel size: 13, 14, 15,and 16 inches in lighter configurations.
Lightness and corrosion resistance
Because the chassis and drive-train components will have expect to be submerged, the materials will have to be corrosion proof. Since material lightness is also a criteria to minimize the need for buoyancy, and also to allow for airborne transport, the materials of choice are stainless steel and corrosion proof aluminum, and perhaps more exotic and expensive allows.
Interchangeability of parts, and ease of repair
Parts should be interchangeable between the size categories to allow for modification and development at the user end, possibly between missions. Since the chassis component is independent and self-supporting, it can be used as a platform for any system. Ease of repair and modification combined with light weight and highly reliable parts should create demand for civilian use that is presently only supported at high cost. The chassis arrangement night be called a "mazarati-jeep."
Since the engine compartment is to be flooded the engine has to be low and specifically designed to be waterproof. Diesel design is easy to make waterproof as the vulnerable component is the air intake. Diesels can have very high performance, but are expensive. Gasoline engines for this purpose would have exceed current expectations. A hybrid design has a benefit for infiltration: total quiet. Waterproof electrical engine systems are available for small submarines, and a hybrid design would presumably extend patrol length. A hybrid vehicle could double as a generator, provide increased starting ability in cold, and possibly boost a diesel vehicles acceleration. As with the chassis, a high-performace hybrid, either diesel or gasoline, would be exceedingly attractive to civilian modifiers. Unlike mechanical through-body connections, which may require the flexible boots that are considered liabilities, electrical through-body connections can be easily sealed.
The final consideration is the water propulsion, and the term "thrust" comes to mind immediately, implying that thrusters are probably the best system for the form car.
Kinds of propulsion
There are two kinds of propulsion: propeller and thruster. And there are two kinds of propelled water craft: displacement and planing.
Planing craft climbed onto their bow, or shock, wave and are able to move most of their mass above the water attaining potentially high speeds. The form car will probably never plan because of weight and "friction" caused by wheels and other mechanical components. So this leaves a displacement model. There are two kinds of displacement models: sleek and inefficient. Sleek would be destroyers, mine sweepers, or perhaps even kayaks. Inefficient would be tugboats with barges. Tugboats are typically fit with nozzle arrangements that are collars around the propellers to make them act as thrusters. More pure thruster designs are called "jet tracktors," and have fully internal systems for producing the motion of water. Tracktor designs have been shown to have far more effective "bollard pull" than propeller designs, where bollard pull means that a vessel is held stationary and efficiency is measured by the tension against, say, a rope attached to a stationary object, such as a bollard on a pier. Traktors are also used in high speed craft as well, and thrust systems are used in water skis, which are planing vessels.
Thrust engines are most desirable
Because the form car would be closer to the inefficient model, which supports a thrust implementation, and because thrust systems are shown to provide high speed, a thrust system appears better for the form car than a propeller system, even though propellers are seen on most amphibious vehicles including the "duck." Another advantage of a thruster is that there is no propeller to get fouled by things found in water, and no danger of slicing by a propeller blade.