September 7, 2017

Today is going to be another themed day, just because I am feeling lazy and want to talk about something that's near and dear to my heart, off road mobile homes! Ok, just mobile homes in general. My wife and I have a small 22 foot long RV and we use it to travel around, mostly to San Diego. But eventually we really want to build an offroad capable RV and travel to Alaska and into South America, and maybe even throughout Europe. So this is going to be more of just a wish list. Some of these ideas may very well be already implemented on some vehicles. So here is my wish list:

  1. A hybrid 4x4 drive train with front wheels connected to a diesel motor with (preferably) a manual transmission, and a all electric rear end drive. This is an ideal setup. You get a hybrid setup for traffic and city driving, where the RV can be mostly rear wheel drive, driven on electricity. However, when you get on the freeway, the diesel motor can kick in, and give you good 500+ miles of range or more, depending on fuel tank size. For off road terrain you only need 4x4 occasionally, so the electric motors in the back can be engaged as necessary, and can provide additional torque during steep hill climbs. The advantage of split drive setup is that it provides you a 4x4 system without the need for a drive shaft. This allows the floor of the vehicle to be lower to the ground in the middle, which provides for roomier internals with smaller overall vehicle size.

  2. 80-100 kWH battery pack under the belly of the vehicle. This pack can be used for the rear drive train and should provide 100-150 or so miles of range for a vehicle this size. However, it can also be used to operate the air conditioner and all of the electricals inside the vehicle. The battery pack would be flat and installed in the subfloor of the vehicle to keep the center of gravity as low as possible. Obviously, in a tall vehicle, such as an RV, keeping center of gravity as low as possible is a priority.

  3. To complete the electrical system, the entire roof of the vehicle would be covered by high efficiency Photovoltaic (PV) Solar modules. The PV modules would be spaced about an inch above the actual roof of the vehicle for better ventilation and, as a result, heat insulation. Based on my calculations, a small 21 foot RV should have enough area for a 1.2-1.6kW array.

  4. The PV modules would have a builtin system of small diameter water pipes running through the back of the module. When the sun is hitting the modules, a pump would continuously circulate antifreeze through the solar panels and a heat exchanger installed inside the hot water tank. We can't circulate the water directly, because it might freeze in extremely cold climates, rapturing the pipes. This has 2 beneficial effects. First, it would reduce the operating temperature of the modules, which in turn significantly increases their efficiency and power production. Second, obviously, you get hot water for free! So it's a win-win. The system of pipes needs to be relatively small in diameter, however, for weight considerations.

  5. The cabin of the RV would be heated with in floor water heating. The "free" heat from the above solar panels would be used to heat the rest of the RV when it's cold. In this case, I am not sure if it's better to use another glycogen antifreeze system or use the hot water directly. When in storage in extremely cold climates, the pipes may freeze over. This could be solved by using an automated draining system or a separate heat exchanger system with antifreeze. In any case, when the solar panels do not generate sufficient heat, a high pressure diesel burner will also heat the water tank.

  6. The RV would have a row of vents, about 1.5 inch tall and about 2 foot wide located around the perimeter of the roof line. These vents would be electrically operated. The idea is to use the natural tendency of heat to rise to evacuate hot air from the vehicle in hot climates. Smaller number of similar vents would be located around the perimeter of the floor, to allow cool air to come in even if all of the windows are closed and covered. Obviously, all of the vents would have metal mesh screens on them to keep critters out.

  7. The roofline of the RV would have a set of 8 wide angle cameras installed around the perimeter, to provide a full 360 degree view of the area around the vehicle. These cameras will feed into a DVR system with a WiFi interface so they can be viewed from a smartphone or a laptop. It's especially useful when camping in the RV in the great outdoors, and you want to see what's happening outside without having to open the windows. Plus it's great for security. Eventually the same cameras could be used for autonomous driving.

  8. One of the RV sides next to the dining table should have a split gate like system where the part of the wall from the middle to the floor line can be opened downward on a hinge, to form a balcony like structure and the top portion of the same wall can be opened upward to create a canopy. Then the diannate can be slid out to provide a more open experience. This would be a very interesting feature, especially when camping.

  9. Front area should have a driver seat and a bench seat for 2 passengers, with a gap in the middle. On a wider vehicle, such as an RV, there should be plenty of space for such an arrangement. The third seat is for a dog or a child seat. We don't have a child yet (yes, one and done, because overpopulation is a problem), but our dog constantly wants to sit in the front seat and feel all important. This would solve that problem.

  10. The vehicle would be equipped with an onboard reverse osmosis system for taking in drinking water from opportunistic sources such as rivers and lakes and a charcoal, canister based, filtration system that would allow you to filter and dump gray water when camping outdoors. Gray water doesn't need much filtration, as it's basically just sink and shower water, so it wouldn't pollute the environment as long as you lightly filter it with a charcoal filter. Black water is from the poop tank, and you have to dump that out properly. I am not sure if I am for or against cassette style toilets, haven't made my mind up yet.

Ok, so I have probably sufficiently bored you with all the ideas I have for my ideal RV. Again, most of these are probably not all that new, it's just a collection of things I would really want in an RV. The list goes on, such as large under the vehicle refrigerated space, drop down bad with skylight, etc. But that would be cruel to you, the reader. Plus some time soon I'll have to also tell you about all the ideas I have for the ultimate catamaran :)