An engineer mods Porsche 911

[cRiPpLe_rOoStEr]

Originally Posted by kach22i

The one issue I didn't see him address is the weak spot in most cars, where the large holes in the side of the car are - called doors. Even more flex is Targa and Convertibles with no top to arch over the doors and complete a box shape.

Normally in so-called full roll cage these issues are addressed.

Falling just short of a full roll cage are rocker panel reinforcements that are often triangular in shape from foot-well zone going upward to middle part of B-pillar.

When a car "folds in half" it is the area around the doors that "give it up" and allow the occupants to be crushed. Stiffing this area stiffens the chassis considerable but comes at the cost of ease of entry and exit.

Reminds me of the BMW i8 with its quite high door sills. Not so hard to slide inside, a PITA to get out.

[some_other_dave]

Originally Posted by kach22i

The one issue I didn't see him address is the weak spot in most cars, where the large holes in the side of the car are - called doors.

Toward the end of the second video, he mentioned he would be adding the back half of the roll cage. That implies that the front half is either in there already, or is at least planned.

The most effective cages serve as space-frames and go to the suspension pickup points, holding them in place relative to the rest of the car. Some rule sets prohibit that, or limit the number of attachment points, so that is not always done. (There may be other, e.g. aesthetic, considerations as well.)

Originally Posted by California98Civic

A lesson of the video might be that the Tesla truck might have a lot more rigidity than an F150, assuming its odd look is because it is a true "space frame" rather than a ladder frame.

Does the Cybertruck have a space frame? That almost always refers specifically to a structure made of some sort of tubing, consisting of mostly triangles for strength, with lots of space in between them. I would have thought that the Cybertruck had a unibody or possibly monocoque construction.

Yeah... A quick Google search shows Musk talking up the "exoskeleton", which looks more like a monocoque or semi-monocoque than a space frame.

Oops, looks like I may have slipped back toward hair-splitting. Sorry!

-soD

[freebeard]

My understanding is that the four wheelwells have the thicker material on the inner wall as well, making four monocoque boxes. The triangular truss has vertical componenets. That's a Vierendeel truss

Here's an ontopic Porsche hybrid moncoque/space frame.

[cRiPpLe_rOoStEr]

Originally Posted by some_other_dave

That almost always refers specifically to a structure made of some sort of tubing, consisting of mostly triangles for strength, with lots of space in between them.

A space-frame doesn't need to be always a tube-frame.