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Launch Cage Test Day + MD80

Discussions about water rocket powered cars, sleds or boats.
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Spaceman Spiff
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Re: Launch Cage Test Day + MD80

Post by Spaceman Spiff » Mon Mar 07, 2011 12:17 am

thampson wrote:Hi USWaterrockets,

They are not running as webcams at the moment (although its a good idea, I might try that, I have the webcam software). I just set it up where I want it, take a 10 second or so video, then just download it to the laptop and see if Im happy with the location and the view it gets. This is how I managed to get the final location after a few different tries.

I just took delivery of a second MD80 clone camera which I will fit to the car as well, so I have 2 cams onboard. I thought I may be able to have the second one viewing sideways just behind the front wheel and place small meterage signs every 10 metres along with the marks on the road to make it easier to verify as the car went over the line markers .. im not sure yet .. I will see how it looks on the video.

One thing we noticed on the last test day with the line marks was that they didnt come out well on the camera at speed.

cya
-todd-

Seeing the lines on the road I think is going to be a problem because the low angle makes the lines look really narrow. That is why if you look at the marks that say "R.R. X-ING" or "NO LEFT TURN" that they paint on the road up close they are really stretched out to be super tall letters. That way from the distance looking forward the letters are compressed by the low viewing angle.

You would need to paint really fat lines to see them from the car easily.


Spaceman Spiff
"What goes up, must come down"

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thampson
Current WRA2 Dragster Speed & Distance Record Holder
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Re: Launch Cage Test Day + MD80

Post by thampson » Mon Mar 07, 2011 1:04 am

Lisa,

I inadvertently came across some thicker chalk on the weekend. My daughter wanted me to draw a track down our driveway for her to ride her scooter, so I used a piece of plasterboard (gyprock, drywall, gypsum board are other names for it) it was about 12mm thick and made some really nice visible white lines down the driveway. I am going to roll the car down the driveway with the camera on to see how visible it is on camera.

The reflective tape would work, but id need heaps of it and I dont think it will stick well to the asphalt :( I hope the plasterboard chalk above will be a cheap and effective way to make the lines, also a bit of rain and they are gone ;)

I do like your idea of using bottles for the markers as I can fill them with water so they dont blow over :) Just need to find some space in the car for 20 of them to get them to the launch site ... LOL !!!

-todd-


HHWRSA
Hornsby Heights Water Rocket Space Agency
http://wrocket.hampson.net.au

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Spaceman Spiff
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Re: Launch Cage Test Day + MD80

Post by Spaceman Spiff » Mon Mar 07, 2011 10:37 pm

thampson wrote:Lisa,

I inadvertently came across some thicker chalk on the weekend. My daughter wanted me to draw a track down our driveway for her to ride her scooter, so I used a piece of plasterboard (gyprock, drywall, gypsum board are other names for it) it was about 12mm thick and made some really nice visible white lines down the driveway. I am going to roll the car down the driveway with the camera on to see how visible it is on camera.

The reflective tape would work, but id need heaps of it and I dont think it will stick well to the asphalt :( I hope the plasterboard chalk above will be a cheap and effective way to make the lines, also a bit of rain and they are gone ;)
I do like your idea of using bottles for the markers as I can fill them with water so they dont blow over :) Just need to find some space in the car for 20 of them to get them to the launch site ... LOL !!!

-todd-

Todd, how about taking along a stack of those brightly colored plastic drinking cups! Fill them with a bit of water or sand and place them along the track. Dump them out and stack them up when you are finished and take them home. That would take about next to nothing in space in the car!


Spaceman Spiff
"What goes up, must come down"

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thampson
Current WRA2 Dragster Speed & Distance Record Holder
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Re: Launch Cage Test Day + MD80

Post by thampson » Tue Mar 08, 2011 6:57 am

Hi Spaceman,

Thanks thats a good idea too. I was thinking about whether I needed to actually have the distance numbers on the bottles / markers as they may not be readable at that speed/distance. As long as I can count the coloured cups on the video as they go by that would suffice I think, as they will usually be 10m apart. Maybe just label them every 50m :)

I will try the $2 shop to see if I can find any, thats a great car space saving idea ;) thanks

-todd-


HHWRSA
Hornsby Heights Water Rocket Space Agency
http://wrocket.hampson.net.au

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Spaceman Spiff
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Re: Launch Cage Test Day + MD80

Post by Spaceman Spiff » Tue Mar 08, 2011 4:57 pm

thampson wrote:Hi Spaceman,

Thanks thats a good idea too. I was thinking about whether I needed to actually have the distance numbers on the bottles / markers as they may not be readable at that speed/distance. As long as I can count the coloured cups on the video as they go by that would suffice I think, as they will usually be 10m apart. Maybe just label them every 50m :)

I will try the $2 shop to see if I can find any, thats a great car space saving idea ;) thanks

-todd-

Glad you liked my idea Todd!

My next brainstorm is that you could also "color code" the cups to mark off the distance. For example for very 5 red cups you put in a blue one. That would make counting the cups easy!


Spaceman Spiff
"What goes up, must come down"

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thampson
Current WRA2 Dragster Speed & Distance Record Holder
Current WRA2 Dragster Speed & Distance Record Holder
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Re: Launch Cage Test Day + MD80

Post by thampson » Wed Mar 09, 2011 10:07 am

Your on fire Spaceman .... brilliant !!

Coloured cups look like the way to go :D

-todd-


HHWRSA
Hornsby Heights Water Rocket Space Agency
http://wrocket.hampson.net.au

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Spaceman Spiff
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Re: Launch Cage Test Day + MD80

Post by Spaceman Spiff » Wed Mar 09, 2011 4:54 pm

thampson wrote:Your on fire Spaceman .... brilliant !!

Coloured cups look like the way to go :D

-todd-
I am happy to have you guys to brainstorm with!


Spaceman Spiff
"What goes up, must come down"

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thampson
Current WRA2 Dragster Speed & Distance Record Holder
Current WRA2 Dragster Speed & Distance Record Holder
Posts: 232
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Re: Launch Cage Test Day + MD80

Post by thampson » Thu Mar 10, 2011 9:35 am

I went and found some big plastic bright coloured cups today. The ones we have chosen are 12.5cm (5″) high and have a very vibrant colour. They will also take up to 550ml of water so once in place and full of water they wont blow over.

Each 10m mark will get a “RED” marker and each 50m will be a “BLUE” marker. We will put a “GREEN” marker at the 150′ mark (45.7m) (for the speed record distance)

We tried to get the biggest, brightest ones we could find so that the cups are still visible even if there is a bit of a crown in the road.

here are the cups, we spray painted the green one as there will be only one of them
cups 005.jpg
also to see how big they are, here is the red one compared to a standard plastic cup
img_0432.jpg
-todd-
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HHWRSA
Hornsby Heights Water Rocket Space Agency
http://wrocket.hampson.net.au

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