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Design Philosophy -
Shelter & Toybox
We are interested in
vehicles that serve multiple purposes. Moving us from place to place would
be number one, since this is, after all, essentially the definition of the
word vehicle. Second, it should have enough cargo capacity to haul
selected toys around with us. Third, it must function as a shelter, if
only in an emergency. It would be nice if it could haul all of our toys
all the time but that would probably conflict with design guidelines # 3,
so we probably have to be selective about our toy collection for any given
journey – ah well.
So, a vehicle as transport,
toybox and shelter – the three core features of our concept for an
off-road home. Below are some
of the broad design guidelines we view as driving our conceptual model.
2) Dimensionally Compact
3) Live Out of Rather than Live In
4) Periods of Extended Off Grid Living
5) Carries all of Our Toys
6) Range on a Single Fuel Fill Up
7) Easy Field Maintenance & Repair
8) Grid Independent Fuel
Source ( this is our vaporware concept, but exceedingly desirable )
Road homes with off road capability come in a very wide range of configurations, really limited only by the imagination, budget and the users ability to either make do with very little or inability to do without very much, in the way of “accessories” to live comfortably.
In our design philosophy we believe the advantages of a pass thru between the cab and the living space outweigh the disadvantages. Our only significant concern with this class of design is if that the cargo compartment doubles as both living space and containment for "dinghy" vehicles than use volatizing liquid fuels. The ideal solution perhaps is to design a quick change venting systems for the carried vehicles that prevents fumes from escaping into the air while the in the cargo compartment. ( Off course, an electric "dinghy" completely sidesteps this issue, but that is a whole other, very interesting, project. )
This pass thru design allows for two basic platform configurations, the van or the truck cab with integral cargo box. ( A truck is defined here as typified by engine forward of passenger compartment or cab, and accessible from outside the cab only).
Vehicle as Transport
travel is easy. We aren’t in any particular hurry. We are strongly
inclined to select roads that, coincidentally, are perhaps best
appreciated from a speed of 50 mph or less. Just seems to have worke d out that way over the years. We certainly need a rig that is capable and
comfortable at a cruising speed around 65 mph. We really don’t care to
be tailgated and are certainly not interested in impeding traffic flow in
any case. We do interstates only under duress.
d out that way over the years. We certainly need a rig that is capable and comfortable at a cruising speed around 65 mph. We really don’t care to be tailgated and are certainly not interested in impeding traffic flow in any case. We do interstates only under duress.
We expect to spend a lot of time on gravel roads; county, BLM and Forest Service, so a dust tight passenger and cargo compartments are essential. The next most critical issue will probably be in making the rig as immune as possible to ill effects form washboard, from standpoints of both ride quality and vehicle durability.
We consider four wheel drive to be an essential feature. If nothing else our experiences in a rear wheel drive van on a minimally inclined road with just a dusting of snow are enough to convince us. We know that much tougher situations await in nearly any off road situation. We want the capability of getting as far off of the beaten track as possible. We suspect that a selectable locker in the rear axle of a two wheel drive van would help immensely but we believe that full four wheel drive and low range allows a much better likelihood of getting deeply off road and back out again with minimal grief. Beyond the drive line and any recovery gear we believe that low vehicle weight at maximum load and compact external dimensions will do the most to allow a wider palette of off road travel.
We are looking for extended travel range on a single load of fuel, so we can get farther into the outback and backout again without risking a long stroll with a fuel can as companion. Therefore a high volume fuel tank(s) and low fuel consumption is desirable. Tank volume is mostly a matter of just finding suitable space about the chassis to mount them. Typically, the low consumption characteristic is enhanced via the following design considerations.
diesel fuel over gasoline – perhaps good for a 30% reduction in fuel consumption, probably the single most influential component of this puzzle. Unfortunately this is seriously offset in that diesel availability in the US is not nearly as common as gasoline, especially in the backcountry we wish to frequent. By some accounts, not verified by us for veracity, perhaps 40% of US stations do not dispense diesel fuel. This seems to present an uncomfortably high possibility of being stranded at an inopportune moment.
engine design – engine specifications should be optimized for minimal fuel consumption, mitigated by the necessary balance with a minimum acceptable power output
coefficient of drag – fuel consumption decreases with a smaller better shaped frontal area, fewer components attached to the exterior skin of the vehicle, less ground clearance, smooth underbelly sheeting, properly shaped vehicle tail and smaller cross section tires
vehicle weight – fuel consumption decreases with lower total loaded vehicle weight
Easy Field Maintenance & Repair
We are highly motivated to avoid any extended down time, complicated diagnostic routines, or nasty repair bills once we have the rig up and running. We believe the best way to this end is to choose an American vehicle that utilizes components with a long production history and available from most of the domestic chain auto part supply houses, are commonly found in salvage yards across the country and are familiar to any competent automotive machine shop.
So, having firmly stated this, now watch us whole heartedly violate that design guideline because we are suckers for the vintage aesthetic and certain admittedly quirky vehicles. Definitely a case of do as I say, not as I do. Given this weakness in our engineering resolve, the best we can do is make component and system choices that will minimize the likelihood of the problems we listed in the first sentence. As much as we wish it weren’t so we have concede that electronic ignition and fuel injection as indispensable to our performance goals, especially with regards to accommodating severe changes in altitude and optimizing fuel mileage. We will just break down and pack spares of the relevant black boxes in case of trouble. We have also become convinced of EFIs role in significantly reducing piston ring and cylinder bore wear so we expect a much longer run before rebuild as well.
The only other issue is just how comprehensive a collection of tools and spares is necessary to cover likely maintenance and repair scenarios. Tools are heavy and they are best stored in a toolbox, which takes up precious volume in the cargo compartment.
Vehicle as Shelter – Living Out of Rather than Living In
There are rigs out and about in the world that not only carry the kitchen sink, but an entire kitchen suitable for a full size, land locked house. To each his own. For our purposes, however, the design goal is to keep our off-road home as light and as compact as we can be comfortable with. The intent here is too increase the range of terrain conditions that can be successfully negotiated without grief. To this end we are willing to forego the kitchen sink etc. Consequently, we select base vehicles that tend to be on the smaller size and concentrate on efficient packaging of the interior components and compact stowage of the exterior components. Rather than selecting interior furnishings, components and utilities from the RV and Marine worlds, we look to the backpacking and camping worlds for lighter, more compact substitutes. We also believe strongly in the concept exemplified by the Murphy bed, components that fold out into working height during use and fold in to a compact, smallest footprint storage space when stowed. We view the cargo compartment as storage primarily and living space only when conditions outside are unpalatable. The design intent is to live out of the vehicle rather than in it. Consequently the design brief will strongly focus on efficient deployment and stowage of addendums to the main vehicle structure to accommodate kitchen, bedroom, toilet and general lounging activities.
We want the freedom to indulge long term off the grid living but still have the benefits of electricity. Consequently our design brief includes a system of PV panels, house batteries and inverter to power lighting, a microwave oven, computer and potentially satellite internet. Extended outback stays, if dry camped, would also require large volume of potable water storage on board.
We are generally quite content sleeping in tents at ground level, but we fully expect to spend a fair amount of time hanging out in bear habitat, if only because they seem to be resident in some of the most appealing back country in North America. So, pitching the tent atop the roof is in the cards as an option, but unlike the common flip top tent camper configuration, our design will simply provide the option of pitching the tent, or perhaps just a canopy, on a roof mounted platform. The platform design needs to be carefully integrated with the PV panel array to prevent blockage of sunlight. Fortunately the most probable times for tent usage, night and foul weather, are poor opportunities for PV utilization anyway.
Vehicle as Toy Box
Oh boy, where to start. We want to carry; an all-road motorcycle of the single cylinder persuasion, an all-road bicycle, a watercraft ( probably folding ), backpacking gear, both summer and winter editions ( think snowshoes), hunting ( archery ) & fishing gear, snorkeling gear, tools for toy maintenance. Your collection may vary, but we think our example is pretty comprehensive and if we can satisfactorily fit all of it in our rig, perhaps you can make some tentative assumptions about your own vehicle and toy collection. Clearly the motorcycle is the biggest space hog and we will have to work out some compromises to accommodate it. One option is to carry it on an external rack but for numerous reasons we aren’t going to go that route. The most significant conflict is using the cargo compartment when the bike is lashed down inside. Since the design intent is to live out of the vehicle except during extenuating circumstances, a primary design goal is to allow camp set up without disturbing the bike. If taking refuge inside the vehicle’s cargo compartment becomes necessary, we simply have to unload the motorcycle for the duration. PIA as that is, at least it is a relatively quick and painless process. Remind me I said that when I wake up to a blizzard, with a couple of feet of snow on the ground, and have to load the bike back into the vehicle.( Note: need a cargo floor tarp and drain system for circumstances like that ). Of the other large toys, the bicycle and the watercraft should be relatively easy to store and manipulate.