Robot Aerodynamics

I recently put my robot in a windtunnel and got mixed results. The Lexan curving upwards at the bottom of the bot supplies great downforce, allowing me to grip the field better. I think this will help with defense and overall speed. However, the Lexan curving upwards at the top/hood, negates this downforce, and the flat piece at the back provides much resistance. Overall, I was fairly happy with it. I was wondering what results you got when you tested your robots in windtunnels, as this is an essential part of robotics at the vrc and vexu stages.

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No offense but I cannot tell it this is sarcasm or not. I have never seen anyone test robots in wind tunnels because the V5 motors are strong enough to make air resistance negligible.

In defense, you made me think about something. I am wondering if a V5 drone is possible if you shape the robot as a plane with wings instead of a quadcopter.

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The problem with a vex drone is the thrust to weight ratio issue. That would be less of an issue with a fixed wing plane. You might want to use a non vex battery to power the v5 or control the motors without the use of the v5. Using stock batteries will limit flight time to 3-5 minutes.

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i use flow, so my robots always have low air resistance. i also learned that if you fillet every c channel, gear, and roller, the robot goes 5% faster. this is based on accurate readings from wind tunnel testing. i recommend everyone try this, because filleting c channels, gears and rollers will help u win.

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“The derivative of jerk is snap, crackle, and pop”
The derivative of filleting is snap, crackle, and pop… Coincidence, I think not!

Filleting source:
image

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i firmly believe physicists found a way to smoke sum rice crispy cereal the day they termed the derivatives of jerk

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Attack is better because it can grab the air and push off of it. I tested this in the wind tunnel and found that with flow, you are more prone to defense because you flow with the air.

Wait wait wait. Does attack actually give you 3% more torque? And flow 2% more speed? I thought that was a joke…

yes it does. but do your own research. vex is about learning and experimentation, get ur own results and verify it. only way to improve in the real world

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Y’see, I totally would, but I, unlike some people, don’t have access to a wind tunnel.

u can use a simulation instead of a real wind tunnel

matlabs is free for students in VRC

I did some research and the conclusion was that a typical snail has aerodynamic profile which allows it to reach speeds of up to Mach 3 as long as you have enough engine thrust.

Snail shells have excellent strength characteristics to survive both high Gs and max q but the main area of concern is to protect the soft yummy body of the snail from the effects of the dynamic heating and violent turbulence at high speeds.

In my opinion, the most promising technology that offers adequate level of protection is Soul Armor but, unfortunately, the tests have been pushed back to Aug 28 due to the covid pandemic.

video of the lower atmosphere testing

UltimateSnailbot

Additional test results with pre-launch countdown are available in this topic.

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Proceeds to import robot in real world into cad. Computer crashes because the robot model makes no sense because you don’t know got to drill holes in stuff properly. Then once the model finally loads it gives you a 100% air resistance. Maybe this explains why your motors overheat and you robot doesn’t move. Ignoring the fact that you drilled holes in the motors to save weight.

You should also explain the the real life to virtual downloader why you have 100 1/8 screws to make sure your claw bot doesn’t fall backwards. Or maybe how you got 2 brains plugged into one motor to have more processing power. And the 4 batteries teetered to you 12 controllers so you can always switch out batteries during a comp.

I also should say that I tested this with my bot im assuming the meta this year is to Swiss cheese your motors to save weight for your claw bot so you shouldn’t even have test this out.

My code on github if you wanna test out a non-meta design

What program to use for code

You need to open up Kahn academy and go to the java script coding lesson there and copy the code into a new project

I hope this helps you guys and thank for listening to my TED talk

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We swiss cheesed our robot brain last season and it allowed faster cooling and dissipating static shock into the air. Highly recommend it.

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thank you for your research.

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