Sketchup designs

Shown below are two figures from the same point of view. Facing the passenger cab is the top right of each figure, and the bottom left of the pictured truck bed faces the tailgate.

Figure 1: Unrolled bed

Figure 2: Rolled-up bed

After careful consideration for the brainstorm ideas, the following elements have been included in the Sketch-up design in order to visualize the layout:

• The twin bed rolls out, laying between the wheel wells. Approximately 1 cm of space should exist on each side.
• The sink and stove will occupy the pictured spaces at varying times.
• The stove is to fold down
• The sink will slide horizontally over the stove
• A custom cutting board will cover the sink with a lip to prevent movement
• The potty is pictured on the bottom right of both figures
• It will be a composting toilet, sitting tall enough for personal comfort, leaving enough room for composting reactions
• In Figure 2, the bed is rolled up, revealing black mats and a wooden platform
• The black mats will be similar to upholstered seat cushions in three large sections to provide comfort under the bed
• These mats can fold up to encase the bed, creating more usable surface area, and protect the bed from dirt
• The surface under these mats may be carpeted for increased sitting comfort and dirty boots/gear when necessary
• To allow drainage, the wooden floor is a slatted surface with a slanted under-layer
• The shower, toilet and kitchen will be located in this section
• The toilet will rotate to face the stove area when in use, then store in the pictured position
• The shower will be sectioned off, perhaps by a zippered section or curtain
• Shelving pictured in the figures are placeholders for everyday storage (clothes, food, hygiene, supplies)
• The right side of the bed has been left empty aside from the toilet. Remaining space will be used for other essentials (currently undetermined).

Kitchen

• The kitchen will be situated toward the tailgate of the truck, next to the sanitation area
• It must be able to stow away and be out of the way due to safety concerns
• If an emergency arises, occupants must be able to leave the camper quickly. There must be as few obstructions as possible by the doorway in order to ensure safe and quick leave of the space.

Ideas so far:

Actual sink

• Unlike most other campers out there, this camper will feature an actual sink, similar to those found in Tiny Houses.
• Some campers have fold out plastic sinks or buckets. Backpacking supply offers folding or pop up sinks that stow away in a small footprint
• The sink top can be covered by a cutting board or other platform when not in use to increase usable surface area.
• Considering: Lillangen (Brand), a small rectangular sink with built in lip
  

Sliding sink

• the sink will be mounted to a sliding platform that will allow use in the kitchen when necessary, but sit above the wheel wells when in storage

A protective kitchen cover

• If going with the idea of making the camper a bathtub, the kitchen will need a cover of sorts to keep water out in the event of a shower or potty use
• Covering up the kitchen when going potty is important due to sanitation concerns
• It is undesirable for kitchen items to become wet upon showering
• Refer to the "sanitation" section for more details on covers

Sanitation

Brainstorm ideas

Shower:
-a zip-off privacy shower/bathroom area.
--similar to an "airlock" as an initial entry space that would also act as a weather resistant barrier.
--entry would be similar to that of a tent, 3/4 way zip

-Make the whole camper a giant bathtub
--Think of a wet-room
--all cabinetry and bedding would need to store into (or be) waterproof areas
--slatted floor with a tilted floor underneath to allow drainage
--privacy curtain for residents in simultaneous shower, if more than one individual


Potty:
-bucket potty
-cassette potty
-tilted potty to allow more headroom
--seems uncomfortable, might not be too sanitary depending on gender and type of "business"
-composting potty (turns waste into soil)
-emergency potty only, find a place for number 2

Insulation

The insulation for the truck is necessary for maintaining a comfortable and habitable temperature within the camper itself. Space and safety considerations are extremely necessary as certain insulation types are more suitable in this context than others. The already small volume of the camper does not allow the luxuries of thick insulation in order to maximize living space.

Ideas:

Remove the truck bed liner and spray foam the camper shell and truck
--Adhesion of the foam would be permanent.
--Delamination would not be an issue.
--To remove, the foam can be scraped off all surfaces. The camper shell is made of fiberglass and coated for    sharps hazard safety, which means the shell is not a smooth surface, rather rough and non-uniform in              texture.
--Permanent adhesion to the truck frame and shell is not desired.
--Spray foam is very porous and flaky, which can be damaged easily and would require paneling/sheathing      for protection.
--Spray foam's insulating value is approximated R-5 to R-6 per inch (Wikipedia) (note: look for other              sources)


Fiberglass Batt insulation
--Made of fiberglass = batt insulation would be difficult to work with in terms of safety. Proper PPE                (Personal Protective Equipment) such as long sleeves, gloves, eye protection, safety (face) mask, and a hat    should be worn to prevent improper/unhealthy exposure to fiberglass in an enclosed space.
--Batt insulation is required to be sealed against human contact to prevent health risk. In residential                  construction, this is most often accomplished with the drywall installation.
--A quick Home Depot search returns R values estimating 3-4
--Undesirable to work with on a personal level


Foam Board insulation
--Average R-5 to R-6 per inch for common foam board insulation
--Safe for human contact and exposure without PPE
--Easy to work with: shape, adhere, move, transport, etc
--Easily damaged - must be sheathed/paneled to protect boards
--Reflective coating reflects thermal energy back into the open space. In other words, the space will maintain heat a bit better.
--Could allow condensation build-up
--Not necessarily "waterproof", but surfaces are "wax coated" and mildew is unlikely to grow on these boards. Waterproofing might be necessary depending on design and further research.


Insulating the Bottom of the truck
Ideas:

Cut out the base of the liner to install rigid foam insulation
--requires sheathing/paneling to protect the boards from damage
--If including a reflective barrier, an air gap would be necessary for the sheathing/paneling. No current working ideas for ways to float the floor to maintain the required structural strength (to be a floor) while maintaining insulation integrity. NO gaps


Layers!
Cut out the base of the liner, leave the wheel wells attached. In the shape of the cutout, replace with the following layers from base of bed and up:
corrugated plastic sheet (provides easy removal without damaging the foam, provides slight air gap between truck and foam to increase insulation by trapping air and reducing conduction)
furring strips (or slats) spaced out across plastic
reflective rigid foam insulation filling in the gap between furring strips
(furring strips must be taller than insulation boards for necessary air gap and prevent compression of foam board upon applied load)
spray foam seam between filler boards and furring strips, trim [spray foam] as necessary.
1/4 inch plywood on top, or some sort of structural flooring

considerations:

• bathtub floor requires waterproof surface
• whole panel can be divided into 2-3 large sections for easy installation/remove if necessary. Depending on design, individual sections may need to be watertight.
• cover the whole panel (all layers together) in a plastic sheet to prevent water damage/penetration.
• (Sectioned shower only) A waterproof layer (plastic/shower curtain) or vapor barrier shields layered panel contacting shower section, running along underneath shower panels

Prototype so far
Rigid foam boards were chosen to insulate the camper. The space has been divided into the following panels:
-Camper shell (Completely insulated)
--Ceiling
--Front wall and window cutout
--Side walls and respective window cutouts
--Back window with cutouts for locking mechanism
-Truck bed (Not completely insulated)
--Sidewalls (between liner and truck frame)
--Front wall (between liner and truck frame, interfacing with passenger cab)
--Tailgate (mobile panel split in two, inside camper, against liner)

Un-insulated:
-Truck floor
-Wheel wells

Prototype Testimonies
-Sitting in the sun for weeks, the cab can be unbearable. However, open the tailgate and stick your head in immediately - the place might feel cozy. The temperature within the camper was actually very comfortable. As a metric, a car that had been parked for one hour with the sunshade up in the middle of the afternoon feels stifling upon entry.
-A quick test one afternoon with an ambient thermometer showed a ten degree decrease in temperature inside the camper compared to the outside reading.

For full entry, please reference Field Test Notes.
Upon testing the camper in cold weather as insulated above ("Prototype so far"), the camper insulated pretty well in the cold to a comfortable temperature. A draft seemed to pass through the camper, traveling out the floor of the truck, and similarly out holes within the insulation at the corners of the truck. Since thermal energy is transferred from hot to cold, heat was essentially leaving the camper through the uninsulated floor. The temporary blankets, carpet, and sleeping bags did not do well for insulating the space.

Elements to include and consider

• Materials Selection
• Durability
• Corrosion
• Thermal conductivity
• include calculation for foam thickness
• Cost
• Recyclability
• Mass
• Potential for mass manufacturing?
• What is currently out there?
• Capable of modular design?
• Market?

Sleeping Space

• These are all brainstorm ideas with commentary.
• The initial design incorporates a sleeping area that will fold up and stow away, or be re-purposed for a different function.
• Images are included as examples.

Build a platform that disassembles easily:


Lay a bed out between the wheel wells of the bed.
options:

1. The bed would fold, like a futon, into a couch position
1. Futon thicknesses are approximately 5 inches. When sitting on the futon, there may not be sufficient head space for the average male height (~5'9"), as female average heights are commonly lower than men's. 
2. Folding a cotton futon of 5" depth is also difficult to do in a limited space. The item is heavy and does not hold new shapes readily nor well. On the up side, since the futon is made of cotton, folding would not be an issue for extreme temperature ranges.
2. The bed could be a foam material that is cut and puzzle-pieced together to ensure separation does not occur in sleep. The puzzle pieces can be disassembled, stacked, stowed away or used as chair cushions.
3. Memory foam
1. Most memory foam mattresses are approximately 7 to 12 inches in depth, which would exceed the amount of headroom available for comfortably sitting upright in the bed.
2. Memory foam mattress toppers range from 2.5" to 5" in depth.
3. From experimentation:
1. These toppers are extremely easy to fold and move around.
2. Lightweight
3. Holds new shape readily in warm (or room temperature) conditions.
4. Very difficult to fold when the mattress is cold, though becomes pliable with ample body heat.
5. Is not ample as a single layer against the corrugated truck bed liner. Laying a rug and foam similar to play-mats under the mattress made the mattress vastly more comfortable.
6. Bottoming out is extremely uncomfortable and not a viable long term option
4. Camping mattress pads
1. These can be blown up in a dozen or so breaths
2. Store easily
3. Sat on comfortably without touching the floor when inflated
4. Commonly water resistant
5. Can be expensive (~$100 each)
6. Insulated models, some with heat reflective coatings

Overview

To start, the objective of "Under the Camper Shell" is to be able to design and build a prototype camper within the bed of a pickup truck and its camper shell. With that build envelope in mind, the amount of space available is extremely limited, making versatility, modular design, and efficiency extremely important components in the success of this project.

The prototype is designed to be a fully enclosed living environment in an urban setting. The unit will contain basic spaces for sleeping, cooking, and sanitation. Recreation/work space will also be incorporated in the design.

The prototype will be built within a 1996 Toyota Tacoma with a mounted camper shell.