Underslung loads

JBee

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That's not how government acts, laws or rules work. By what law could you be prosecuted if there is no law to stipulate the committed offence? Sorry, but that's plain ridiculous. If it were true they could stop writing laws and regulations. No point in discussing that anymore, talk to a lawyer, or read the homologation rules in your country, or anything about how intent law can be applied. :rolleyes:

Regardless, on the technical side, there is "zero" difference on the height above the ground between the van frame (of which I have the exact same model and can measure from) and the proposed underslung CT height (that I have in a dimensionally accurate, within a few mm, CAD model as below). Given this there is no difference in the likelihood of hitting something on the ground with CT underslung or the Van side frame. In fact you could argue the side frame is more prone to hitting a high curb. It is most definitely not to low, in fact by doing an exact model as below, I found it can be 40% lower than originally estimated, it's now 9" instead of 5". A 5" underslung would have 4" extra clearance (that's a sportcar clearance) extra again. So easily fits.

This render below of the CT with the suspension up has a 9" (230mm) high underslung storage box attached to the bottom, and it still has the same clearance as when the CT is in it's lowest highway setting. (This is going off 14" of travel, even though the UI patent etc show 20"). Meaning the clearance with underslung box is within the design constraints of the CT when the suspension is in highway mode. No difference.

It is clear by this that the underslung storage box is in no way impeding the operation or safety of the vehicle. (For those interested, the box is 1270mm wide, so you can drive over it to pick it up, and has a volume of about 1.3m³)

Feel free to bring some physical evidence to the discussion to prove your point.

Tesla Cybertruck Underslung loads 9inch Underslung Storage 3
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BillyGee

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Congrats. You might be the most dedicated person on this forum to stupid ideas.
 

JBee

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Congrats. You might be the most dedicated person on this forum to stupid ideas.
Thanks for the compliment buddy! :cool:
Wouldn't be the first time a genius idea is called stupid.

Have a good day! :)
 
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BillyGee

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Nobody makes dehydrated water or clown dating apps either, doesn't mean they're good ideas.
 

JBee

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Nobody makes dehydrated water or clown dating apps either, doesn't mean they're good ideas.
Why wouldn't clown dating apps work? I would of thought I'd be able to find you on there?? :p
 
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FutureBoy

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OK.
While I'm not thinking I'll use anything like this on my CT, I did find that it is not an uncommon thing for vehicles to have items hanging under the body.

There is even a patent for underslung cargo containers.

Let's see some examples of underslung or underbody items.

Truck Tail Lift
Tesla Cybertruck Underslung loads Underslung Lift

Notice the attached lift accessory hanging off the back of the truck. Found the image here. It's listed as a feature of the truck as an "Underslung Tail Lift".
Items like this can also be purchased here.

Underbody Tool Boxes
Lots of trucks have various boxes hanging from the frame. Using brackets like these. And boxes like these.
As demonstrated here. Or here. Or here.

Other Items
Underslung engine
Underslung water tank
Underslung spare tire, or this one, or this
Underslung generator and another one

Early Example
As it turns out, some of the very early electric cars used to hang their batteries under the body of the vehicle.
Tesla Cybertruck Underslung loads fig148-frame-battery-cradle

Of course, these vehicles were probably not traveling nearly as fast as I expect my CT to be able to handle. But I wouldn't say the roads they traveled were any less bouncy than what one will encounter these days.
 

Crissa

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- road debris can dislodge it
- raw materials risk damage
- increased high point risk
- wedging and ricochet avoidance window shortened
- possible battery damage from carried materials
- no structural protection in case of tire failure
This is ridiculous.

Road debris can bounce a load off the roof, too.

If you're lowered for highway efficiency you can hit road debris, too. The first Model S battery fire was from that.

No, you don't have an increased high point risk unless you're jumping curbs. Which why would you do with a load?

If your materials can damage the battery, you were already in really big trouble.

If your tire blows, your roof-mounted load is going to shift madly, too.

As long as you know the road, there's not going to be an increased risk. Unused height is unused height.

-Crissa
 

Crissa

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<Snip>

It is clear by this that the underslung storage box is in no way impeding the operation or safety of the vehicle. (For those interested, the box is 1270mm wide, so you can drive over it to pick it up, and has a volume of about 1.3m³)
Luv the render! Thank you. Building breakover angle into mine for driveway and approach aprons.’Cuz suspension bounce.
Tesla Cybertruck Underslung loads 4D952EFE-E25C-481E-AF37-E4B5DAFA73A1
 

BillyGee

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Technically, sure, do whatever you want. You all are just nitpicking this idea which no regular truck user would ever do, but go for it. Prove the world wrong by using the least safe position to store things. There's the tops, sides, bed, bed trunk, drunk, cab, there's even trailers, but no... Clearly the undercarriage is just wasted space.

There's inherently risk in operating a vehicle with a load. There's ways to mitigate and amplify this risk. Storing things six to ten inches from a bench grinder is still a worse idea than storing them on top of the car. No amount of contrarianism or nitpicking will change that.

Tesla Cybertruck Underslung loads DEahC53VYAArOAu
 


Red61224

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That's not how government acts, laws or rules work. By what law could you be prosecuted if there is no law to stipulate the committed offence? Sorry, but that's plain ridiculous. If it were true they could stop writing laws and regulations. No point in discussing that anymore, talk to a lawyer, or read the homologation rules in your country, or anything about how intent law can be applied. :rolleyes:

Regardless, on the technical side, there is "zero" difference on the height above the ground between the van frame (of which I have the exact same model and can measure from) and the proposed underslung CT height (that I have in a dimensionally accurate, within a few mm, CAD model as below). Given this there is no difference in the likelihood of hitting something on the ground with CT underslung or the Van side frame. In fact you could argue the side frame is more prone to hitting a high curb. It is most definitely not to low, in fact by doing an exact model as below, I found it can be 40% lower than originally estimated, it's now 9" instead of 5". A 5" underslung would have 4" extra clearance (that's a sportcar clearance) extra again. So easily fits.

This render below of the CT with the suspension up has a 9" (230mm) high underslung storage box attached to the bottom, and it still has the same clearance as when the CT is in it's lowest highway setting. (This is going off 14" of travel, even though the UI patent etc show 20"). Meaning the clearance with underslung box is within the design constraints of the CT when the suspension is in highway mode. No difference.

It is clear by this that the underslung storage box is in no way impeding the operation or safety of the vehicle. (For those interested, the box is 1270mm wide, so you can drive over it to pick it up, and has a volume of about 1.3m³)

Feel free to bring some physical evidence to the discussion to prove your point.

9inch Underslung Storage 3.png
Ever been "High Centered"? You end up feeling just as vulnerable as an overloaded cart and donkey.
Tesla Cybertruck Underslung loads 1626026036170


Watch your loads, otherwise, you may end up with your ass in the air.

You will have more control of your CyberTruck cargo if you used an overhead rack or I hear there is this wonderful invention called a TRAILER which is much safer and less vulnerable to "bumps in the road" and other things which you have no control of such as driveways, rough ground, objects in the road, potholes, armadillos....... yada, yada, yada.
I wonder if the suspension height may be speed limited like in max height for off-road purposes ONLY. I would not want to have much speed on all jacked up.
 
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All that you've demonstrated with those two pictures is that there are three more sides to a vehicle that are safer to load items onto than one that is mere inches away from pavement screeching past it.

There is no reason to put anything under a vehicle like this, full stop. Feel free to do it when you do get your cyber truck, make sure to tell every highway patrolman that stops you and tells you how illegal it is that I told you so.
My original suggestion was to use the air suspension to maintain the ground clearance you'd normally have. So if you have 8" clearance normally, you could lift the truck to the full 16" clearance and use 8" of space to haul things.

In retrospect, the only way this would work safely is if Tesla supported it and was able to lock the suspension into a higher position.
 
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Technically, sure, do whatever you want. You all are just nitpicking this idea which no regular truck user would ever do, but go for it. Prove the world wrong by using the least safe position to store things. There's the tops, sides, bed, bed trunk, drunk, cab, there's even trailers, but no... Clearly the undercarriage is just wasted space.
Where are you getting this idea that the underside is the "Least safe position" to store loads?

Don't tell this to truckers who use it for chains, toolboxes, and spare tires. Fuel tanks are commonly the lowest thing on trucks, hung under the cab. A huge number of vehicles store their spare tire underneath the vehicle.

Top, bottom, side, underside, inside, outside, whatever storage choice you use is as safe as the engineering to support it is.
 

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Under the frame and above the axles is much lower risk than directly across the entire underside.
 

FutureBoy

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Under the frame and above the axles is much lower risk than directly across the entire underside.
I'm thinking this is a false comparison. Tesla CT won't have a solid axle across the bottom. At full height, an underslung package could be below the motors but still be above the center point of the tires.
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