Sunday, September 29, 2019

Vehicle-buggy accidents, Part 5: Putting some of the pieces together

Plan view of ladder frame
A quick recap of where we are to date and to marry some of the ideas together.

A ladder frame is welded of 2"-by-4", 16 gauge steel. It is composed of two longitudinal members, approximately 36" apart. All members are in the same plane and all sectionss are in "portrait" orientation.

The first cross piece from the left is to stabilize the longitudinal members as they crush. The second, third, fourth and fifth cross pieces are for seat attachment.

Side view
We still have the issue of rearward pitching of the occupants because the force the bullet vehicle is applying to the frame is below the buggy+occupant's center-of-gravity.

One detail to help address the pitching is to add a detail to the rear of the longitudinal members to stick the ends into the bullet vehicle like a dart. The detail should span from 16" above ground to 24" above ground to maximize the chances of hitting significant structure in the bullet vehicle's body. Hardened steel points...say 2" long, Grade 8 bolts with the tips ground into 45 degree cones... increase odds of penetrating flubber and "sticking" into bumper bars or other metal.

The sticker plate will punch through plastic and thin metal and embed in solid structure in the bullet vehicle. Most bumpers are curved in the plan view and cause the longitudinal members to splay out-of-position unless you tie them together or have a sticker-pad.
Damage done to the bullet vehicle is energy our structure does not need to dissipate. It is one of the energy sinks labeled "other".

The sticker pad helps control the pitching by forcing the entire structure to rotate around the rear of the vehicle, increasing the apparent rotational inertia.

Current state: 
  • The buggy is now stuck to the front of the bullet vehicle and both are moving 26 miles per hour. The mass of the buggy slightly slowed the bullet vehicle
  • 12-to-24 inches of the longitudinal members crushed in an accordion-pleat fashion.
  • None of the passengers experienced fatal trauma unless they weighed less than fifty pounds and were not in a protective, child seat.
  • The seats are in the full rearward position but will flop forward as soon as the frame starts to decel
  • On decel, the occupants will fly forward, out of their seats unless they have some kind of restraint.
  • The front of the frame is lifting upward
  • The front of the frame is about to impact the rear of the 1000 pound horse at 26mph. That impact will further slow the assembly to 23mph.

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