Amazing robot! I was wondering how you got your hard stop to not bend like crazy with all that force? I see a high-strength axle but is that it? Wouldn't it be louder?
There is some non-slip foam on the catapult that absorbs a lot of the force. You do have to check the hard stop every once in a while to make sure it is straight.
From the defense it has encountered so far, it seems to work pretty well -- the robot shots are pretty low to the ground, but if you shoot the triballs with enough force, they tend to bounce up (depending on the opponent's robot design) when hitting the defense and manage to go over the barrier still. If you can't really get any triballs over the barrier from the defense, you can always try switching match load stations. As for the question of full videos of the scrimmage, we probably won't post them because some of the teams in attendance did not compete at Mall of America and we do not want to leak all their strategies / full abilities of their robots without their consent.
Do you mean the rubber links on the catapult? Their purpose was to make the back of the catapult longer so that the tribals would shoot lower (without them, the tribals tend to have a higher arc --> since, without the rubber links, the back of the catapult would be shorter and the tribals would not have to move as far to not be contacting the back of the catapult (since catapults utilize centripetal force while in motion)) while maintaining the ability to go under the goal (since the rubber links can flex). I assume the motors in question are the ones in the "motor box" at the back of the robot (or do you mean the four 11-watt drive motors?). The "motor box" had two 5.5-watt motors and two 200 RPM 11-watt motors stacked on top of each other (they were alternating between 5.5-watt and 11-watt motors to make the motor box slightly thinner and smaller so that it could fit between the drive base c-channels). The motors on each side of the motor box were connected together by low-strength 36-tooth gears (the PTO was connected to the bottom motors of the motor box). The motor box was attached to the robot by a whole lot of standoff bracing (basically wherever some could fit. It was also sandwiched inside the robot tightly enough that even if all the bracing came undone, it would not fall out of the robot).
Awesome video! I had a similar idea in mind for the drive where you utilize some 600 rpm motors and some 200 rpm motors with it all geared together properly, but I was worried about the motors longevity fighting against each other as some burn out faster or spin at slightly varying speeds. Have you guys noticed anything like that with your design?
It causes the triballs to go roughly 3 more feet on average before hitting the ground. It is so we can shoot from the match loads and still have the potential to make goals as seen in our reveal.
@@lettucejr9678 Mostly because of the spacing of the drive. Flex wheels also have a lot of grip on the middle bar and they can deform easily so that the drive can cross smoothly.
How do you make sure during match loading when people push you around and you move you. You don’t engage pto a bunch of times and you don’t run out of air?
It really just comes down to the question of when to use the PTO and when to go as a 4-motor drive. Four motors were enough to be able to cross the barrier, so you only really need the PTO for pushing the defense away (If the defense does not let up, you could always try switching to the other match loading station to score a few).
Great explanation. I dont entirely understand how your PTO works. How is the cylinder attached to the gears and drivetrain in order to actute them between the cata and the drivetrain?
The 36-tooth gears are sandwiched between two lexan pieces which are attached to the cylinder (it's very difficult to see because the PTO is buried pretty deep within the robot). The pneumatic cylinder for the PTO is attached to the robot by two screws at the very ends which run through pillow blocks and allows the cylinder to freely engage and disengage the PTO without the cylinder falling out.
Also, one other thing was that, instead of something like a sliding shaft, the 36-tooth gear of the PTO slid on some square inserts (the ones that come with the 12-tooth pinions).
Interesting concept! We have ordered some pneumatics from vex (we are a new team) but from what I can tell from pictures online there are only holes on the far side of the pneumatic cylinder (not the side where the pin part extends outwards) so how would you attach the two screws? Is there some other part that we would need to order to make this part (what are the 'low strength pillow blocks'). Sorry if I am not making sense, I have never used the vex pneumatics before? Thanks.
Very cool robot. Just wondering how did you shave down the metal slip gear I’ve seen most are plastic so you just use a file but how can you do it with a metal gear
The locking mechanism only locks when there is force on the wings. When there is nothing pushing against the wings, the locking mechanism is a few millimeters away from the lexan catch, which allows the wings to easily fold back in.
well, no kit .. we just buy a good selection of parts every year to make the robots... it's good to have a stock of basic parts as well as a good selection of any other parts you think you will need for your final design
@@robokauz how exactly a ratchet can lock the catapult in place in the fully tensioned down position? do you need to use a pneumatic to control the ratchet? is there a UA-cam video somewhere that explains that? we are new to VEX and would love to learn more
@@cuongcjnguyen4405 Kepler Electronics is a great place to look at ratchets, their channel has covered that. the ratchet is not necessary for a catapult but it helps the motor.
wait i have a question that i really hope you can clarify for me. if your catapult is 33 rpm how are you getting 100 shots per minute since you are shooting 33 times per minute at 33 rpm right?
So the slip gear spins at 100 rpm which determines when it shoots. But it connects to the catapult in a 1 to 3 ratio resulting in the catapult moving at 33 rpm
Unfortunately, the robot does not exist anymore. However, here are a few things about it: - The Drive RPM was 360 on 4" wheels. - It could switch between a four-motor and seven-motor drive - there were two 2" flex wheels between the 4" wheels to help cross over the barrier. Hope this helps :)
well i cant explain the physics in text very well, but the mechanism rotates the half-cut high-strength shaft around the axis at the end of the cylinder, driving the shaft into the catch on the side of the robot so it cant slip. I hope this helps
I have been sitting here for hours trying to figure out how you did this locking mech and it just doesn’t seem to be working Is there any way you could help me?
I hope I can So the beck of the high strength shaft has to be tensioned to the robot to ensure that it is close to the catch on the robot. You want the wing to rotate the shaft around the end of the cylinder which will force the catching end of the high strength shaft into the side of the robot. This second part is how it works … it rotates around the end of the cylinder as the wing is pushed back, which coincidentally pushes it to the catch on the side of the robot. Hope that helps
thank you another question how far away is the tension from the end of the axel? I counted around 6 holes, also is the axel tightly attached to the wing?
With motors you shouldn’t need a locking mechanism. It should work if your motors are set to hold. We are just using locking mechanisms because the pneumatics are not at strong as motors and the air pressure can be driven back under force.
@@coltonhenry7373 I’m not sure what your wings look like, or what mechanism you use to open them, but if they are directly powered by motors then the bands might not be necessary.
In sorry we dont have an up to date full CAD of this robot that is able to be put out. However you are welcome to watch this video and our reveal video to get ideas on how you can fully build and design a robot with the same overal design.
The slip gear 12 teeth, spins at 100 rpm while the catapult arm , attached to a 36 tooth gear spins at 33, but since the slip gear goes at 100 rpm it slips and fires 100 times per minute
That wing lock is sweet
Your bot looks great! Can’t wait to see you guys at Speedway.
i like that retractable locking mechanism on the wings
Hey, I was wondering if you could show off how you deploy your intake and keep the chain tensioned.
Would you be able to make a video explaining your intake?
Would have been so good at MoA
Fr
Sheeeeeesh!
Amazing robot! I was wondering how you got your hard stop to not bend like crazy with all that force? I see a high-strength axle but is that it? Wouldn't it be louder?
There is some non-slip foam on the catapult that absorbs a lot of the force. You do have to check the hard stop every once in a while to make sure it is straight.
Very interesting, do you have any ideas on hanging yet?
yooo so cool, maybe I need to reconsider how much drive power I need...
Amazing Bot! How well does the cata shooting perform against defense? Is it possible to post any of the scrimmage matches?
From the defense it has encountered so far, it seems to work pretty well -- the robot shots are pretty low to the ground, but if you shoot the triballs with enough force, they tend to bounce up (depending on the opponent's robot design) when hitting the defense and manage to go over the barrier still. If you can't really get any triballs over the barrier from the defense, you can always try switching match load stations.
As for the question of full videos of the scrimmage, we probably won't post them because some of the teams in attendance did not compete at Mall of America and we do not want to leak all their strategies / full abilities of their robots without their consent.
Where did you guys get the cad file for your controller add-ons?
Please go over the intake 🙏🙏🙏
Where do you get the metal 12 tooth gear?
Very epic robot
Was there a reason for the rubber links on the 4-bar intake?
Oh, also, how'd you mount the motors vertically like that?
Do you mean the rubber links on the catapult? Their purpose was to make the back of the catapult longer so that the tribals would shoot lower (without them, the tribals tend to have a higher arc --> since, without the rubber links, the back of the catapult would be shorter and the tribals would not have to move as far to not be contacting the back of the catapult (since catapults utilize centripetal force while in motion)) while maintaining the ability to go under the goal (since the rubber links can flex).
I assume the motors in question are the ones in the "motor box" at the back of the robot (or do you mean the four 11-watt drive motors?). The "motor box" had two 5.5-watt motors and two 200 RPM 11-watt motors stacked on top of each other (they were alternating between 5.5-watt and 11-watt motors to make the motor box slightly thinner and smaller so that it could fit between the drive base c-channels). The motors on each side of the motor box were connected together by low-strength 36-tooth gears (the PTO was connected to the bottom motors of the motor box). The motor box was attached to the robot by a whole lot of standoff bracing (basically wherever some could fit. It was also sandwiched inside the robot tightly enough that even if all the bracing came undone, it would not fall out of the robot).
How is the high-strength axle you guys use for your hardstop attached to your robot? I can see some holes drilled in the sides, but no apparent screw?
it looks like its attached w a screw attaching it to the top of the piston and its pulled w a rubber band keeping it straight
Hi, we are a new VEX team, and we are wondering were you got your High Strength Axle from? the VEX website we cant find anyone piece that width.
Awesome video! I had a similar idea in mind for the drive where you utilize some 600 rpm motors and some 200 rpm motors with it all geared together properly, but I was worried about the motors longevity fighting against each other as some burn out faster or spin at slightly varying speeds. Have you guys noticed anything like that with your design?
no we have not encountered that
Thanks for posting an explanation about your robot. Can you explain how your catapult releases, is it your ratchet that releases the tri- ball?
its probly a slip gear
What kind of motors on drive base?
How did u hold the brain there and put it at an angle?
what is the gear ratio, and how much teeth are shaved off of the slip gear?
Robokauz pretty cool no cap fr
What's the difference between a shot with the ramp engaged and not? What's the purpose exactly, and what does it change?
It causes the triballs to go roughly 3 more feet on average before hitting the ground. It is so we can shoot from the match loads and still have the potential to make goals as seen in our reveal.
what part did u guys use for the pusher? the one where u guys tied a rubberband unto it?
Cut high strength axle
How are you using a normal shaft collar on a HS axle? Did you just drill them out?
We filed them out very time consuming but worth it
The cross court scoring on this robot is insane! I love robokauz :D
What's the purpose of the 2" flex wheels on your drivetrain?
I would assume to make crossing the middle bar easier.
Oh ok, that makes sense. But why flex wheels over non-compliant wheels?
@@lettucejr9678 Mostly because of the spacing of the drive. Flex wheels also have a lot of grip on the middle bar and they can deform easily so that the drive can cross smoothly.
How do you make sure during match loading when people push you around and you move you. You don’t engage pto a bunch of times and you don’t run out of air?
It really just comes down to the question of when to use the PTO and when to go as a 4-motor drive. Four motors were enough to be able to cross the barrier, so you only really need the PTO for pushing the defense away (If the defense does not let up, you could always try switching to the other match loading station to score a few).
Robokauz op
Great explanation.
I dont entirely understand how your PTO works. How is the cylinder attached to the gears and drivetrain in order to actute them between the cata and the drivetrain?
The 36-tooth gears are sandwiched between two lexan pieces which are attached to the cylinder (it's very difficult to see because the PTO is buried pretty deep within the robot). The pneumatic cylinder for the PTO is attached to the robot by two screws at the very ends which run through pillow blocks and allows the cylinder to freely engage and disengage the PTO without the cylinder falling out.
Also, one other thing was that, instead of something like a sliding shaft, the 36-tooth gear of the PTO slid on some square inserts (the ones that come with the 12-tooth pinions).
@@stuartblank21417 Many thanks for the detailed reply. In regards to the pillow blocks, are you using the high strength ones or the regular LS ones?
@@TheRealAlexGray It uses low-strength pillow blocks.
Interesting concept!
We have ordered some pneumatics from vex (we are a new team) but from what I can tell from pictures online there are only holes on the far side of the pneumatic cylinder (not the side where the pin part extends outwards) so how would you attach the two screws?
Is there some other part that we would need to order to make this part (what are the 'low strength pillow blocks'). Sorry if I am not making sense, I have never used the vex pneumatics before? Thanks.
I have a question, Can you make a lift to elevate your alliance to the elevation bar?
in the game yes you can but i also still have yet to see a team hoist another up for a better score
Very cool robot. Just wondering how did you shave down the metal slip gear I’ve seen most are plastic so you just use a file but how can you do it with a metal gear
Cut it
Grind teeth off with a grinder.
Belt sander, did mine with one and turned out really well
How many pistons are you guys using for the PTO?
there are 2 ptos on this robot. each one uses one cylinder, although our new robot uses 2 cylinders for one pto
How are the wings able to close so easily even with the locking mechanism?
The locking mechanism only locks when there is force on the wings. When there is nothing pushing against the wings, the locking mechanism is a few millimeters away from the lexan catch, which allows the wings to easily fold back in.
w
omg
Well hello there, a fully functioning robot I see, HMMMMMM!!!
What kit did you use to make this?
well, no kit .. we just buy a good selection of parts every year to make the robots...
it's good to have a stock of basic parts as well as a good selection of any other parts you think you will need for your final design
someobe @ me if you make a video explaining the intake please
how you can keep the catapult in the horizontal (close) position? do you do it by programming the cata motor?
Programming then it is turned on. A ratchet when it is off
@@robokauz how exactly a ratchet can lock the catapult in place in the fully tensioned down position? do you need to use a pneumatic to control the ratchet? is there a UA-cam video somewhere that explains that? we are new to VEX and would love to learn more
@@cuongcjnguyen4405 Kepler Electronics is a great place to look at ratchets, their channel has covered that. the ratchet is not necessary for a catapult but it helps the motor.
wait i have a question that i really hope you can clarify for me. if your catapult is 33 rpm how are you getting 100 shots per minute since you are shooting 33 times per minute at 33 rpm right?
So the slip gear spins at 100 rpm which determines when it shoots. But it connects to the catapult in a 1 to 3 ratio resulting in the catapult moving at 33 rpm
@@robokauz oh dam that makes so much sense tysm i never thought of it like that but its basically the same idea as a puncher.
Quick question, for your catapult, what do you use for your limit switch?
we use a rotation sensor/ encoder
@@robokauz do you use a PID on your rotation sensor?
Plastic screws and nuts are legal this year?
Yes
how many teeth did you shave out of the 12 tooth slip gear
3-4 teeth
How did you cut the high strength shaft
We used a plain hacksaw, vice,and lots of patience
What is the car in the background?
2004 PT Cruiser
Could you show us and explain the drive train?
Unfortunately, the robot does not exist anymore.
However, here are a few things about it:
- The Drive RPM was 360 on 4" wheels.
- It could switch between a four-motor and seven-motor drive
- there were two 2" flex wheels between the 4" wheels to help cross over the barrier.
Hope this helps :)
@@stuartblank21417 How comes you got rid of the robot? Looks pretty good imo?
Hey, I was wondering how many teeth you took off the slip gears?
6 , but it varies depending on the specifics of the robot, I'd start with less, then work your way up to however many you need to get rid of.
@@robokauz alright thanks!
How many teeth were shaved off of the pinion gears?
6, but it varies so for your build you may want to start out with less teeth shaved off, then work your way up.
how does the wings lock work?
well i cant explain the physics in text very well, but the mechanism rotates the half-cut high-strength shaft around the axis at the end of the cylinder, driving the shaft into the catch on the side of the robot so it cant slip. I hope this helps
What about the arm that shot out?
that was a small wing to get the triball out of the match load area
how do you half cut the HS axle
Precision dremeling
Hack saw.
Handsaw and a belt grinder
I have been sitting here for hours trying to figure out how you did this locking mech and it just doesn’t seem to be working Is there any way you could help me?
I hope I can
So the beck of the high strength shaft has to be tensioned to the robot to ensure that it is close to the catch on the robot.
You want the wing to rotate the shaft around the end of the cylinder which will force the catching end of the high strength shaft into the side of the robot. This second part is how it works … it rotates around the end of the cylinder as the wing is pushed back, which coincidentally pushes it to the catch on the side of the robot.
Hope that helps
thank you another question how far away is the tension from the end of the axel? I counted around 6 holes, also is the axel tightly attached to the wing?
@@saltinecrackers5414 no all attachments are lose. The tensioning shouldn’t matter too much as long as it keeps the shaft close to the robot
Thank you very much I figured it out
Do people just not try for the climb or something?
I think it's just bc it's early season, and people are trying to perfect their other systems first
Hey we were just wondering whether the bearings for the wings were made out of custom plastic, or does vex sell something for that?
No it’s custom polycarbonate
Is it legal to use the brain as an ramp?
yes, its not against the rules because it is vex equipment 😉
It's legal, but remember that the brain has to be easily visible, and the power button easily accessible per R25
i dont have pnumatics how would i do a locking mechinism with motors
With motors you shouldn’t need a locking mechanism. It should work if your motors are set to hold. We are just using locking mechanisms because the pneumatics are not at strong as motors and the air pressure can be driven back under force.
thank you@@robokauz
should i take my rubber bands of the wings then???
@@coltonhenry7373 I’m not sure what your wings look like, or what mechanism you use to open them, but if they are directly powered by motors then the bands might not be necessary.
thank you@@robokauz
Great Reveal! Was wondering if you would be willing to share your robot's CAD design with us, as we are new to VEX? Many thanks.
~Isaac W (78116B)
In sorry we dont have an up to date full CAD of this robot that is able to be put out. However you are welcome to watch this video and our reveal video to get ideas on how you can fully build and design a robot with the same overal design.
how do you make the half cut high strength axles
Take a high strength axle and cut it in half
Put the high strength shaft in a vice and cut it down the middle with a hacksaw
@@stuartblank21417hacksaw sounds terrible use power tools💀💀💀
I though plastic screws were made illegal
They were last year but they are legal this year
@@robokauz ok tx
33rpm doesn't sound like it is 100 shots per min
The slip gear 12 teeth, spins at 100 rpm while the catapult arm , attached to a 36 tooth gear spins at 33, but since the slip gear goes at 100 rpm it slips and fires 100 times per minute