Trunk and Roof Props

2 BAR LINKAGE SYSTEM

• 

  Link to a gif showing a similar system: https://gifs.com/gif/r83AgW

• Pros:

  • Relatively simple mechanism

    • Two rods connected by an internal pin. At the end points are mounted to external pins

    • To lock the two linkages a variety of systems may be used:

To lock it in place an intermediate brace piece can sit under the internal pin connection (as shown in sketch below)

• 

• Note the physical connection from the brace piece to Link B can take many forms

  • A manual pin that slots into Link B

  • A pin that pushes against a “single direction locking arm” (see sketch below for clarification)

  • 

Less mounting space required compared to other concepts

• Only need two mounting areas for the external pin connection (one on the trunk, the other on the side panel)

Cons:

• Can only lock at one height

• Will need additional components to have a supported closing of the trunk

  • i.e. in its current form you must manually close the trunk to prevent it from slamming

SINGLE SLIDING BAR MECHANISM

• A single bar is mounted to two external mounting pins

  • One is on the trunk

  • The other is mounted to a shaft that it can slide along or may be a pin restricted in its motion by a slide opening

    • 

    • If a pin and slide opening is used, the following mechanism could be used to lock the mechanism

      • Link: https://youtu.be/5JQkzjj_cxs?t=65 (watch until 1:34)

      • Notes:

        • In some versions of this type of mechanism it is quite difficult to get the pin past the spring loaded latch

        • This mechanism will require additional mounting space and hardware

        • Integrating the pin may be difficult

        • Will have to correctly spec out / design spring loaded latch

• Pros:

  • Relatively simple in nature

    • Only requires shaft, single linkage and external pin mounts

  • Allows for locking at variable heights

  • Could (relatively) easily integrate a supported closing mechanism

    • At the very end of the shaft would need something to slow the velocity of the bottom mount

  • Adaptable

    • Allows for the ability to become a motorized system

    • Can just as easily work as a manual system

• Cons:

  • Will need lots of horizontal room for the shaft

  • Securing may not be easy to do in a way that doesn’t require manual input

  • May weigh more than other designs due to the shaft

COMPRESSED AIR SUPPORT STRUT

• Similar mechanism to conventional cars

• Will work in a similar manner

  • Two attachment points, one on the trunk another on the side

  • When opening the piston will extend

    • At apex the compressed air supports the piston, preventing it from contracting and the trunk closing

  • When closing, the force you exert will be greater than what the compressed air within can resist

    • Causing the piston to contract and the trunk to close

• Pros:

  • Allows for supported closing of the trunk

  • May be more lightweight compared to other solutions

• Cons:

  • Probably will need to purchase this

    • May be hard to find one that has the exact specifications we need

    • If we get ones that are too highly overspecced, it will take a higher than normal amount of force to close the trunk

  • May be hard to integrate these factory components (which are designed for specific makes and models of production cars) into our custom car

    • Mounting may be an issue

SCISSOR JACK MECHANISM

• Top of scissor jack will mount to roof, bottom of scissor jack will mount to side panel

• Will work as conventional scissor jacks do

  • Threaded bar is spun

    • Clockwise or counterclockwise spin will cause jack to raise or lower

• Pros:

  • Can have automatic opening and closing of trunk (if a motor is used)

    • Users do not need to physically open the trunk

  • Can support the roof at a variable angle

• Cons:

  • If a motor is used, this is another element that will draw power from the battery box

    • Also will add additional weight (on top of the scissor jack itself)

    • Will require power and control wire connections

    • Would be hard to integrate a manual operation of the scissor jack

      • Physically moving the motor’s axle may cause grinding of internal motor gears

  • If no motor is used (manual operation only) this would be physically strenuous

  • Will need horizontal space for the threaded bar to extend into

SINGLE SLIDING BAR MECHANISM

• Similar to the one described for the Trunk

  • However could use the existing chassis tubes as the shaft

2 BAR LINKAGE SYSTEM

• Similar to one described for the Trunk

  • Could have second mounting point on the existing chassis tubes