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Tech Spam thread - because 1/4" BSP gets 5 hand spans to the jiggawatt

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keen to play crew chief for team trident 323

 

so shock pots needed and high speed camera of 60ft plus GPS

 

 

what GPS have you got dave/ you probably posted this elsewhere.

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Pity I'm not tech savvy, or smart enough to keep up with this thread.

I was day dreaming about steam engines one time, (I think it was after watching Thomas the tank engine at Karl's actually)

And though thought occoured to me that if you had a steam engine, you could drive a turbo of some kind using the steam exhaust pulses. And thus cram more air into the fire box/combustion chamber. I mentioned it to my Dad, and he reckoned they used to discharge it into the smoke stack to create a venturi effect behind it to draw more air into the firebox. (He might actually be old enough to remember actual steam trains)

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who uses what program as a point cloud processor to then output to a solidworks compatible format.

Vague questions are the best questions

as per cam said, vrmesh to make pointcloud reasonable size & removing redundant data without loosing much quality (ie 1gig scan data to 15 meg for like a engine block)

then pointcloud to stl,

at that point, instead of doing spline patches just to get into shitty models, i have been just exporting the stl and also the points just as dxf, overlaying them in xyz package and using 3 points on "faces" to make planes, curve@intersection of plane and stl etc. this is because bothering to surface them only made life 0.01% easier downstream for 100% more work upstream, the only downside ive come accross is obviously no add/subtract body functionality but meh

also its nice in vrmesh to export "important bits" with more data,

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Pity I'm not tech savvy, or smart enough to keep up with this thread.

I was day dreaming about steam engines one time, (I think it was after watching Thomas the tank engine at Karl's actually)

And though thought occoured to me that if you had a steam engine, you could drive a turbo of some kind using the steam exhaust pulses. And thus cram more air into the fire box/combustion chamber. I mentioned it to my Dad, and he reckoned they used to discharge it into the smoke stack to create a venturi effect behind it to draw more air into the firebox. (He might actually be old enough to remember actual steam trains)

Steam engines run on heat, and in the first 'pump' they havent used it all up. So some have 2 or 3 (or more?) chambers where it goes from first, to second, to third.

 

So the air that comes out the end of all that doesnt have much energy left.

image31.jpg

By the 'end' of steam trains they had them figured out pretty well.

 

 

as per cam said, vrmesh to make pointcloud reasonable size & removing redundant data without loosing much quality (ie 1gig scan data to 15 meg for like a engine block)

then pointcloud to stl,

at that point, instead of doing spline patches just to get into shitty models, i have been just exporting the stl and also the points just as dxf, overlaying them in xyz package and using 3 points on "faces" to make planes, curve@intersection of plane and stl etc. this is because bothering to surface them only made life 0.01% easier downstream for 100% more work upstream, the only downside ive come accross is obviously no add/subtract body functionality but meh

also its nice in vrmesh to export "important bits" with more data,

This is relevant to my interests, how are you making the point cloud in the first place?

 

Is that with your fancy laser scanner thingy?

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I fired on a Peckett steam locomotive on a museum line a few times many years ago. There was a valve controlling what we called a blower to boost the fire a bit. That would be what runamuck refers to.

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We are still trying to deal with point clouds easily in the 10s of millions of points. At the moment I am manually drawing on the semi defined edges (VRmesh will help to clean these up for sure) of the cloud within SW. To me it is a Shitty way of inaccurately building stuff from super accurate information. The problem is the step up to the programs that can better deal with these things are fucking expensive.

I am learning so much about this stz at the moment. I will try and update this as I learn. Haha

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Steam engines run on heat, and in the first 'pump' they havent used it all up. So some have 2 or 3 (or more?) chambers where it goes from first, to second, to third.

 

So the air that comes out the end of all that doesnt have much energy left.

image31.jpg

By the 'end' of steam trains they had them figured out pretty well.

 

Even less energy if you are using the exhaust steam to pre-heat the cylinders?

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Pity I'm not tech savvy, or smart enough to keep up with this thread.

I was day dreaming about steam engines one time, (I think it was after watching Thomas the tank engine at Karl's actually)

And though thought occoured to me that if you had a steam engine, you could drive a turbo of some kind using the steam exhaust pulses. And thus cram more air into the fire box/combustion chamber. I mentioned it to my Dad, and he reckoned they used to discharge it into the smoke stack to create a venturi effect behind it to draw more air into the firebox. (He might actually be old enough to remember actual steam trains)

I fired on a Peckett steam locomotive on a museum line a few times many years ago. There was a valve controlling what we called a blower to boost the fire a bit. That would be what runamuck refers to.

This/both, there are heaps of different designs but both direct steam from boiler to some kind of venturi/blower thingie or very commonly exhaust steam from cylinders to firebox exhaust stack venturi (this gives the classic chooch chooch chooch choooch puffs of black smoke and white steam)

 

Steam engines run on heat, and in the first 'pump' they havent used it all up. So some have 2 or 3 (or more?) chambers where it goes from first, to second, to third.

 

So the air   STEAM that comes out the end of all that doesnt have much energy left.

image31.jpg

By the 'end' of steam trains they had them figured out pretty well.

 

 

This is relevant to my interests, how are you making the point cloud in the first place?

 

Is that with your fancy laser scanner thingy?

 

yeah sorry being a pedantic cunt

 

 

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Even less energy if you are using the exhaust steam to pre-heat the cylinders?

 

you gotta use as close to all of what you can, you usally bleed steam off the HP or IP stage to pre heat the boiler feed water too.  but not so much in a steam train where its running an open loop system without a condenser. no condenser leaves something like 1/2 of the energy or more on the table depending what the boiler steam pressure is.

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We are still trying to deal with point clouds easily in the 10s of millions of points. At the moment I am manually drawing on the semi defined edges (VRmesh will help to clean these up for sure) of the cloud within SW. To me it is a Shitty way of inaccurately building stuff from super accurate information. The problem is the step up to the programs that can better deal with these things are fucking expensive.

I am learning so much about this stz at the moment. I will try and update this as I learn. Haha

 

Just create curve at intersection to pull out good geo

all that happens if you surface the mesh and stitch it into a solid is you still have to do this, as there is obviously no defined edge

its just shitty spline net/patches whatever your terminology is, i can send you an example if you want, so you still have to create curve at intersection of a defined plane anyway to pull info out. 

 

It sounds shithouse as an approach, but you need to change your mindset from scanned model to worlds best verniers with a graphical interpretation to help you draw over, and then get fast at it so its economical. it will never have an edge any better than the above technique no badly how much you beat it to death with rapidform /xyz mesh surfacing software.

 

dealing with these large datasets is always going to be #1 problem, just tiptoe around the edges and bite your tongue/get on with it/wait for someone to invent the magic button.

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keen to play crew chief for team trident 323

 

so shock pots needed and high speed camera of 60ft plus GPS

 

 

what GPS have you got dave/ you probably posted this elsewhere.

It's a 20hz chipset bodged together with an arduino or something something that my Dad pieced together.

It's a Skytraq Venus something something, I think it's an older model now as the ones you get from them are now 50hz.

 

All I know is that it plugs into USB and is damn accurate! With the program Racechrono on a netbook.

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this reminds me, of another thing - wheel speed sensors. has anyone tried to measure using ABS sensor and tone ring? I have a feeling you end up with too high of a frequency for alot of stuff to deal with?

 

mainly thinking of this regarding speed based boost control which is the real deal when it comes to putting big power down with limited traction as it is feed forward control rather than closed loop traction control

which has to see a wheel slipping first, which is likely to upset the car and require a reduction in power application  rather than preventing slip in the first place and the chassis being under a constantly increasing load which is more stable.

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Why couldn't you forget the exhaust venturi,  run a big fuck of turbo and turn the the fire into a blast furnace for super hot fun times/more efficient coal burn...

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The only problem I can see with this is that if all four wheels are spinning, it's going to interpret this as though you're travelling at a higher speed, and so increase the boost and then your wheel spin increases more. Or if just front or rear wheels are spinning... How does it know which ones are or arent? (Is this for Sentras car you're talking about?)

 

Limiting per gear is probably a better option?

 

If you can look at the datalog and figure out the first rpm/load combination that the wheel spins at. Figure out how much HP this is.

 

Then apply the horsepower formula to the rpm etc of the wheel to figure out how much horsepower the wheel can put to the ground at various speeds then limit your boost to acheive approximately that amount of horsepower at each speed.

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