View Full Version : What speed is your Boulder launching at
Just wondering what kind of speeds teams are either seeing or expecting their boulders to be flying at?
We used a radar gun on ours this evening and the team as a whole was smiling from ear to ear. 56 mph or 82fps
Peyton Yeung
15-02-2016, 22:17
Is hella an acceptable speed? Our's moves at about the speed of an unladen swallow.
Tom Line
15-02-2016, 22:23
Over 9000. RPM.
Is hella an acceptable speed? Our's moves at about the speed of an unladen swallow.
African or European?
Ours currently doesn't. I haven't asked just how fast we should actually shoot when we get it built, but a prototype shooting from near the Defenses tried to shoot down any flags that might have been on top of the Tower.
My reason for asking is two fold.. One I am curious by nature, second I am curious to know what teams thoughts are on trying to block shots with their robots knowing the speeds that the boulders are being launched at.
Chris Endres
15-02-2016, 23:52
One might say...ludicrous speed...
Jacob Bendicksen
16-02-2016, 00:09
I am curious to know what teams thoughts are on trying to block shots with their robots knowing the speeds that the boulders are being launched at.
The pool noodle thread (http://www.chiefdelphi.com/forums/showthread.php?threadid=143918) I was just looking at comes to mind...it doesn't take much to deflect even the hardest of shots. Many robots were cheesecaked with pool noodle blockers in 2013, and I expect to see similar strategies employed this year.
Ginger Power
16-02-2016, 00:17
We're somewhere in the range of ludicrous speed to bench grinder.
Speed of light as an acceptable measure of our boulder's speed :D
Tom Line
16-02-2016, 01:20
We're somewhere in the range of ludicrous speed to bench grinder.
Hrm. I suppose putting it in terms of bench grinders would be more appropriate. I hadn't thought of that.
2.1 bench grinders. (Spell correct just tried to change grinders to gingers. Silly spellcheck. Gingers aren't a measure of speed).
hectorcastillo
16-02-2016, 01:41
We launch ours at 88mph during qualification rounds so that they'll move forward in time and all get scored simultaneously in the finals.
Ginger Power
16-02-2016, 07:35
Hrm. I suppose putting it in terms of bench grinders would be more appropriate. I hadn't thought of that.
2.1 bench grinders. (Spell correct just tried to change grinders to gingers. Silly spellcheck. Gingers aren't a measure of speed).
I hear Gingers are pretty fast.
MechMentor
16-02-2016, 07:39
If we shot the boulder through a Chronograph it would be around "Do we really need this much speed and force?" feet per second. It's enough to help a five-ounce bird carry a one pound coconut.
BoilerMentor
16-02-2016, 08:19
Well, the surface speeds on our sets of shooter wheels are 100 and 130 fps at maximum motor output. We generally run it between 60% and 70%. I know we've got a lot of slip. So, the answer is just really, really fast.
It's a fast enough RPM that the difference between VEX hex bearings and VEX ThunderHex bearings may be necessary to investigate.
Conor Ryan
16-02-2016, 08:31
Sounds like we are pretty far away from the Aim High 12fps speed limit.
JohnFogarty
16-02-2016, 08:35
You know those gravitational waves you keep hearing about recently? Those weren't created by colliding black holes, they were created by our boulders colliding with the opposing alliance's tower.
Im not really sure what ours is running at. It was decent speed when we had mini cims geared 1:1 with 3" of compression, but we put SpinBoxes on the mini cims so its geared 1:1.67 now. The wheels are spinning at roughly 10,000 RPM. We are still working on the final arm/ shooter assembly so we don't even know how well this will work compared 1:1.
BetaHelix
16-02-2016, 09:54
Ours shoots fast enough to take out exit signs and castles at range
I_AM_Clayton
16-02-2016, 10:04
Here´s a video of our shooter, its faster than it looks!
https://youtu.be/5XZUleXc4XM
Alpha Beta
16-02-2016, 10:12
Looking forward to the design where "low bar capable" + "high exit velocity" != "blockable". Is the flattest parabola really the best parabola?
Here´s a video of our shooter, its faster than it looks!
https://youtu.be/5XZUleXc4XM
We've found the winner!
At events around the world, pit scouts will ask pit crews "how fast is your shooter" and the correct response is "faster than it looks."
JohnFogarty
16-02-2016, 10:41
Looking forward to the design where "low bar capable" + "high exit velocity" != "blockable". Is the flattest parabola really the best parabola?
You won't have to look further than week 0.5
Louisiana Jones
16-02-2016, 11:41
Looking forward to the design where "low bar capable" + "high exit velocity" != "blockable". Is the flattest parabola really the best parabola?
We have our cheesecake noodle blocker ready to go! Defense is going to shut down some teams.
We have our cheesecake noodle blocker ready to go! Defense is going to shut down some teams.
Shut down? Doubtful as they can still score by damage to defenses and you can only defend one. I don't see a defense bot being much more than a minor annoyance, as usual. Not to say they won't make some difference if you already have two very capable bots. That can weaken and breach. They may help in eliminations assuming the other two can handle all scoring.
In quals I have a feeling defense will be a liability as scoring/RP will be at a premium for teams and its easier with 3 bots versus 2.
Louisiana Jones
16-02-2016, 12:05
Shut down? Doubtful as they can still score by damage to defenses and you can only defend one. I don't see a defense bot being much more than a minor annoyance, as usual. Not to say they won't make some difference if you already have two very capable bots. That can weaken and breach. They may help in eliminations assuming the other two can handle all scoring.
In quals I have a feeling defense will be a liability as scoring/RP will be at a premium for teams and its easier with 3 bots versus 2.
Yeah I don't anticipate defensive robots trying to stop to many robots from going through the defenses because of the penalties for contact in the outerworks, but I do think robots shooting in either the high and low goals will be significantly slowed by a robot playing defense in the courtyard.
We have our cheesecake noodle blocker ready to go! Defense is going to shut down some teams.
Noodles you say? That'll work for the first ball...
Louisiana Jones
16-02-2016, 13:05
Noodles you say? That'll work for the first ball...
yeah, all blockers will have to have a sturdy/flexible support to stay vertical , and to make sure they don't flop over more than 15 inches outside the frame perimeter. In the past we have used PVC with a noodle over it as a blocker.
About 20 fps. Short shot with front bumpers near the batter, long shot with rear bumpers in the outer works.
Fusion_Clint
16-02-2016, 14:22
yeah, all blockers will have to have a sturdy/flexible support to stay vertical , and to make sure they don't flop over more than 15 inches outside the frame perimeter. In the past we have used PVC with a noodle over it as a blocker.
Anyone that successfully blocks our shot will very likely be in violation of G17 or G25C.
jodge1706
16-02-2016, 14:24
Hrm. I suppose putting it in terms of bench grinders would be more appropriate. I hadn't thought of that.
2.1 bench grinders.
Ours has to be at approximately 4.6 bench grinders.... we might need to change some gear ratios :eek:
stopyourself
16-02-2016, 15:25
Well, ours measures in at 27fps at full power...
BoilerMentor
16-02-2016, 16:05
Noodles you say? That'll work for the first ball...
...Not even our first ball. We sent a Garmin VIRB camera flying across the room and still hit the goal. I'm beginning the thing Dirty Harry may have been a more appropriate name for the robot this year.
Nathan Streeter
16-02-2016, 17:53
Sounds like we are pretty far away from the Aim High 12fps speed limit.
Worst rule ever...
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