Yes, when it IS the final nail in the coffin of ICE vehicles.
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Space X Option Package
- Thread starter McManX
- Start date
Yes, when it IS the final nail in the coffin of ICE vehicles.
CarlK
Active Member
True. It's the same as when Tesla spent resources making the original Roadster, the Model S, the Model X and the Model 3. The purpose is not just to gain thaE < 1% of auto market. The purpose is to show the world and traditional auto companies that ICE does not stand a chance. This is indeed the final nail in the coffin. No could ever say again yes it's great but can you do this?
gavine
Petrol Head turned EV Enthusiast
Nurburgring record? Probably by a lot. Hopefully the run it there.
Ben W
Chess Grandmaster (Supervised)
Do you have a reference for the "double digit multiplication factor"? A traditional spoiler accomplishs this by applying torque to the car, but a front-mounted upward cold-gas thruster would apply torque in the wrong direction to substantially increase downforce to the rear axle.
From a physics/geometry standpoint, it would make more sense to point the thruster up and back; say at a 45-degree angle. A pound of force at that angle effectively applies ~0.7 pounds of downforce as well as ~0.7 pounds of forward thrust. With a COG of 1.0, this effectively creates a ~1.4x multiplier in efficiency over a thruster that points either directly upward or directly backward. (Similar logic applies even if the COG is greater than 1.0.) Also, unless the motors combine for >1500 horsepower, they will not be able to sustain >1.5g acceleration past 60mph, regardless of COG/downforce, with purely upward thrust. (Assuming ~3500lb car + driver.) Backwards thrust is required to overcome this horsepower limit. For optimal performance, the thrusters would point more upward at low speed and more backward at high speed.
In any case, if the thrusters were pointed downward and modulated with enough precision, it should be possible for the car to briefly perform a controlled hover, like a Harrier jet. With only cold gas thrusters, and realistic limitations on COPV size, this may be sustainable for a second or two. It would make one heck of a demo; I want to see Elon do it while wearing Doc's metal sunglasses from BTTF.
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CarlK
Active Member
You are missing the real reason why this is so revolutionary. The down force, cog and everything we are familiar with are not relevant now because the car literally "flies". Things we do now are based on force transfer between tires and the road surface. That has been imposing the ultimate limit on everything from acceleration to deceleration to changing directions. With thruster that limitations no longer exist. You certainly can apply more down force but that is actually not needed, if not unwanted, when thrusters are in action.
Well it only would fly for a second or two. Based on the current relative efficiency of aircraft and automobiles, my guess is any initial straight line performance needs some combination of downward and/or forward thrust, not upward.
Ben W:
Not at hand.
My point is, as you nicely demonstrated, the possible ways of using thrusters and maximum effect they can have is a complex problem by itself.
Maximum force a stationary thruster can produce in isolation and not tell the whole story by far.
I do not see how they could achieve short flights but what do I have to base my doubts on? A few years of second grade physics, so I will reserve my judgement and be prepared to be amazed.
Not at hand.
My point is, as you nicely demonstrated, the possible ways of using thrusters and maximum effect they can have is a complex problem by itself.
Maximum force a stationary thruster can produce in isolation and not tell the whole story by far.
I do not see how they could achieve short flights but what do I have to base my doubts on? A few years of second grade physics, so I will reserve my judgement and be prepared to be amazed.
This is how I frame it for now.
Performance is abundant with EVs. grip isn't. Acceleration is less relevant than braking and cornering where you are very limited.
Aerodynamics takes a mass in real time and tries to manipulate it to achieve favorable drag and downforce.
Active aero goes a bit further by offering some flexibility.
The problem is that drag and downforce scale with the square of speed so the whole thing is only useful at high speeds.
A level above would be where you spend energy to accelerate and manipulate that mass in real time and even add thrust. The problem is that you spend energy to fight the air and that's unavoidable with flying things but really inefficient with cars. The upside is that it works at lower speeds too. Peak power is also a limitation , made much worse by the fact that you always spend on accelerating the air. So like a helicopter, a go kart with fans or McLaren F1's downforce creating fans.
Tesla adapts the previous scenario to better fit cars. The biggest gain is that real time is not a limitation anymore. They add storage and they can deploy that mass at will. They can spend energy when not at peak demand and deploy it for a much higher peak so there is a substantial gain here in all areas - peak drag, downforce, thrust.
They are load balancing , we could even wonder if doing it for the electrical grid inspired this solution.
Ofc there is no reason they can't bypass the air tank and simply accelerate and redirect air in real time for smaller boosts.
Continuous flight would be somewhat hard to do with small air intakes and pumps, that's why folks use large propellers but they could glide at high speeds with the right wing like car.
And now I got a question, assuming they accelerate air at intake so they don't simply wait for air to come to them, does the base model have it too and only lacks the air storage tank? So does it have fans or w/e sucking air from front and/or under the car and redirecting it towards rear and/or upwards for much smaller boosts?
Might adjust how I frame this while I continue to digest it but this is how i see it at this time.
And a Bond Edition might just be crazy enough for Musk to do it.
A projectile loading mechanism and a computer vision based targeting system for each air thruster.
In a high speed chase use the air to destabilize the opponent's car
Create an air cushion above the car to catch a falling object or human - Bond jumping from the 5th floor and the Roadster helps him land smoothly in the car. Ability to fly would come on top of that.
They can do that in movies with CGI but the Tesla Roadster could do it in real life.
Performance is abundant with EVs. grip isn't. Acceleration is less relevant than braking and cornering where you are very limited.
Aerodynamics takes a mass in real time and tries to manipulate it to achieve favorable drag and downforce.
Active aero goes a bit further by offering some flexibility.
The problem is that drag and downforce scale with the square of speed so the whole thing is only useful at high speeds.
A level above would be where you spend energy to accelerate and manipulate that mass in real time and even add thrust. The problem is that you spend energy to fight the air and that's unavoidable with flying things but really inefficient with cars. The upside is that it works at lower speeds too. Peak power is also a limitation , made much worse by the fact that you always spend on accelerating the air. So like a helicopter, a go kart with fans or McLaren F1's downforce creating fans.
Tesla adapts the previous scenario to better fit cars. The biggest gain is that real time is not a limitation anymore. They add storage and they can deploy that mass at will. They can spend energy when not at peak demand and deploy it for a much higher peak so there is a substantial gain here in all areas - peak drag, downforce, thrust.
They are load balancing , we could even wonder if doing it for the electrical grid inspired this solution.
Ofc there is no reason they can't bypass the air tank and simply accelerate and redirect air in real time for smaller boosts.
Continuous flight would be somewhat hard to do with small air intakes and pumps, that's why folks use large propellers but they could glide at high speeds with the right wing like car.
And now I got a question, assuming they accelerate air at intake so they don't simply wait for air to come to them, does the base model have it too and only lacks the air storage tank? So does it have fans or w/e sucking air from front and/or under the car and redirecting it towards rear and/or upwards for much smaller boosts?
Might adjust how I frame this while I continue to digest it but this is how i see it at this time.
And a Bond Edition might just be crazy enough for Musk to do it.
A projectile loading mechanism and a computer vision based targeting system for each air thruster.
In a high speed chase use the air to destabilize the opponent's car
Create an air cushion above the car to catch a falling object or human - Bond jumping from the 5th floor and the Roadster helps him land smoothly in the car. Ability to fly would come on top of that.
They can do that in movies with CGI but the Tesla Roadster could do it in real life.
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They could just have preemptive active suspension for potholes so the sensors watch the road and the suspension handles anything normal. With really big ones, it could go around. Active suspension is reactive , it feels the change and adjust and can't fully eliminate the bump. Jumping over maybe as a last resort as it's less efficient.
More fun would be to jump over large obstacles in a high speed emergency. So 250mph( 400km/h) on a future highway with AP in charge, jumping over obstacles would be a key safety feature.
In normal use AP will need to control max speed, make sure you don't count on the thrusters in a turn and don't have enough force available as the air tank empties. Even with AP, to be able take full advantage and maximize speed, AP needs to know the map and plan ahead. But that's an extreme scenario, in normal use no need to be at the edge of its limits. This would be the augmented mode thingy., AP keeping the driver safe. The thrusters would be somewhat useless without. Ofc unlikely that first gen thrusters would be all that evolved.
More fun would be to jump over large obstacles in a high speed emergency. So 250mph( 400km/h) on a future highway with AP in charge, jumping over obstacles would be a key safety feature.
In normal use AP will need to control max speed, make sure you don't count on the thrusters in a turn and don't have enough force available as the air tank empties. Even with AP, to be able take full advantage and maximize speed, AP needs to know the map and plan ahead. But that's an extreme scenario, in normal use no need to be at the edge of its limits. This would be the augmented mode thingy., AP keeping the driver safe. The thrusters would be somewhat useless without. Ofc unlikely that first gen thrusters would be all that evolved.
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Ben W
Chess Grandmaster (Supervised)
Ok, let's see if we can explain the levitation with second grade physics.
SpaceX's COPV's are capable of roughly 6000psi (400atm), and the car weighs about 3000 pounds. So if you poked a half-square-inch (3.225 cm^2) hole in the bottom of the COPV, the escaping air (6000 lb/in^2 * 0.5 in^2 = 3000lb) would be enough to balance the weight of the car, causing it to hover. With the air escaping at roughly the speed of sound (340 m/s), the COPV would lose its air at an initial rate of 340m/s * 100 cm/m * 3.225 cm^2 = 110k cm^3 per second. So a 35 cubic-foot (1 m^3) tank could sustain this air blast for about nine seconds, with the aperture adjusting to keep the downward force constant as the tank pressure drops.
In other words, it's not really about "short flights"; more "momentary hovering". But it would still be fun to watch. With good earplugs.
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Ben W, I’m not sure I understand (or agree with) your maths, but I love the effort and am intrigued by this whole thrusters-on-Roadster idea!!
Roadster On-Car Kinetic Energy Thrusters (ROCKET) being a fully-appropriate acronym...
Roadster On-Car Kinetic Energy Thrusters (ROCKET) being a fully-appropriate acronym...
Ben W
Chess Grandmaster (Supervised)
Ha, nice acronym! Or Fully Autonomous Levitating Chassis Outclasses Nurburgring...
Do let me know which part of my maths you disagree with; to me the calculations seemed airtight
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