Go to Post Whatever you do, do it in graciously professional manner. - EricH [more]
Home
Go Back   Chief Delphi > FIRST > General Forum
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Reply
 
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 11-01-2014, 08:24
stveception stveception is offline
Registered User
FRC #1660
Team Role: Mentor
 
Join Date: Jan 2013
Rookie Year: 2004
Location: New York
Posts: 4
stveception has a spectacular aura aboutstveception has a spectacular aura about
Motion of Projectile App

I wrote a javascript app that visualizes the motion of the ball with adjustable parameters like angle and initial velocity. The app seems to work best in Chrome.

http://hostedfiles.x10.mx/2/2014ball.html

Please feel free to let me know of any issues with the app. Also, you can double check my maths to see if I made any mistakes. I used the formulas from here

I wasn't sure of the terminal velocity. The terminal velocity parameter is used to compute the amount of drag on the ball. Currently the value I'm using is 51.33 which I found is the terminal velocity of a volleyball, so its likely going to be less than that.

Last edited by stveception : 11-01-2014 at 08:28.
Reply With Quote
  #2   Spotlight this post!  
Unread 11-01-2014, 11:11
Edxu's Avatar
Edxu Edxu is offline
Strategy/Scouting Mentor
AKA: Edwin Xu
FRC #4476 (W.A.F.F.L.E.S Robotics)
Team Role: Mentor
 
Join Date: Jan 2013
Rookie Year: 2013
Location: Toronto, Canada
Posts: 190
Edxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant futureEdxu has a brilliant future
Re: Motion of Projectile App

Thanks for making the App!

I just want to know, would it be possible for you to change the input such that we can type in our own figures, instead of using the dial, to increase calculation accuracy?
Reply With Quote
  #3   Spotlight this post!  
Unread 11-01-2014, 11:17
blaze8902 blaze8902 is offline
Registered User
AKA: Buddy McWilliams
FRC #4265 (Secret City WildBots)
Team Role: Mentor
 
Join Date: Sep 2013
Rookie Year: 2012
Location: Oak Ridge TN
Posts: 43
blaze8902 is on a distinguished road
Re: Motion of Projectile App

I believe the terminal velocity is closer to 11.37 m/s.

Edit: That's 36.09 f/s. Sorry, I've always been taught to do all my physics in metric.

Last edited by blaze8902 : 11-01-2014 at 19:47.
Reply With Quote
  #4   Spotlight this post!  
Unread 11-01-2014, 11:19
jertel's Avatar
jertel jertel is offline
Registered User
FRC #0706 (Arrowhead Robotics)
Team Role: Electrical
 
Join Date: Jan 2013
Rookie Year: 2011
Location: Waukeshau, WI
Posts: 2
jertel is an unknown quantity at this point
Re: Motion of Projectile App

Nice work. I couldn't have programmed that.

I do agree with Edxu that changing the values via keyboard instead of a scroll bar would be more convenient. Would your math still work with decimal values?
Reply With Quote
  #5   Spotlight this post!  
Unread 12-01-2014, 15:35
stveception stveception is offline
Registered User
FRC #1660
Team Role: Mentor
 
Join Date: Jan 2013
Rookie Year: 2004
Location: New York
Posts: 4
stveception has a spectacular aura aboutstveception has a spectacular aura about
Re: Motion of Projectile App

Quote:
Originally Posted by Edxu View Post
Thanks for making the App!

I just want to know, would it be possible for you to change the input such that we can type in our own figures, instead of using the dial, to increase calculation accuracy?
Done!
Reply With Quote
  #6   Spotlight this post!  
Unread 12-01-2014, 16:47
RoboticWombat's Avatar
RoboticWombat RoboticWombat is offline
Doctor Robotic Wombat Is In!
AKA: Luke Baker
FRC #4342 (Demon Robotics)
Team Role: Tactician
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Kennett Square, PA
Posts: 6
RoboticWombat is an unknown quantity at this point
Thumbs up Re: Motion of Projectile App

Thank you for making this app. It will be very helpful.
Reply With Quote
  #7   Spotlight this post!  
Unread 12-01-2014, 17:54
Ether's Avatar
Ether Ether is offline
systems engineer (retired)
no team
 
Join Date: Nov 2009
Rookie Year: 1969
Location: US
Posts: 8,100
Ether has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond repute
Re: Motion of Projectile App

Quote:
Originally Posted by stveception View Post
I used the formulas from here.
Caveat utilitor. Quoting from the source:
Suppose, further, that, in addition to the force of gravity, the projectile is subject to an air resistance force which acts in the opposite direction to its instantaneous direction of motion, and whose magnitude is directly proportional to its instantaneous speed. This is not a particularly accurate model of the drag force due to air resistance (the magnitude of the drag force is typically proportion to the square of the speed),
For a given launch speed, you can probably empirically find a value for "c" which is a good compromise. But if you change the launch speed significantly, that empirical value for c may no longer be a good approximation at the changed speed.

It would be interesting to compare the results of the above model to other models recently posted here on CD which implement drag proportional to speed squared.



Last edited by Ether : 12-01-2014 at 18:00.
Reply With Quote
Reply


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 14:32.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi