After the "big find" yesterday/success of the side rollers, the team was a little slow today in terms of working on things other than the intake. Part of this can be blamed on having an early morning meeting, but most wanted to play with the intake, as it is so far the most effective mechanism the team has ever built.
Shooter
Today we took the surgical tubing off again to work on the intake. Basically, the shooter has been put aside over the past couple days, but we will most likely start working on it again soon.
Intake
Today we went ahead and put on the second side roller, so the intake now had the side roller consisting of a BAG motor and a Banebots wheel on both sides. This took up a decent portion of the day for the kids working on the intake, and the rest of the intake time was taken by programmers programming the newly added motor.
Drive Base
Today we finally finished our official practice bot's drivetrain, so all that was left was finishing adding the rest of the electronics onto the bellypan and making the frame to begin remaking everything on the prototype practice bot out of tubing and other more visually appealing and structurally sound material.
Approximate times of working: 8:00 AM - 12:00 PM
Tuesday, February 18, 2014
1/24/2014 Day 20: The Ball Vacuum
Today was one of the better days, and definitely minds were blown. While the past days weren't quite as productive, today was pretty big in terms of moving into the detailed design phase of the engineering process, as the intake and shooter were finishing passing through the preliminary design phase. By far, the video of the intake is one of the best we had this year, as it is still just light enough to see the general fluidity of the ball's motion, but not exactly what is on the intake.
Shooter
Today was not overly productive for the shooter mechanism, as most were working on continuing drive base stuff and working on the intake. As of now, the idea of using the "surgical tubing links haven't been discussed much further, as we have in general been okay with the way the shooter has been functioning thus far. All we are doing for now is improving the other mechanisms to reach to the same caliber as the shooter.
Intake
Today was a beautiful day for the intake. Finally, we added one side roller, consisting of a BAG motor (is a way a "Baby CIM", just a step down from the Mini CIM) and a Banebots wheel, attached a spare talon (talon is a type of motor controller) to the drive base, and wired the motor to the talon and talon to the power distribution board. While this took a while, we did get to test it (click here to get youtube video), and the ball flow was beautiful. This was much more effective than what we were expecting. Before the side roller, the angle of the ball going into the intake had to be within a 30 degree range. Now, we have an angle range of nearly 270 degrees. Our intake also went to working well for an 8" range, now to around a 56" range. The drawings below are not quite to scale, but is hopefully enough to get the point across visually.
Drive Base
The drive base today was worked on a little today, just primarily testing to make sure it works and functions reasonably decently, and adding extra parts (the talon for the extra side intake motors). Also, we almost finished the official practice bot drive base, and it's just a matter of attaching the bellypan with the electronics already mounted, as well as waiting for the 2nd set of 3 CIM single-speed gearboxes to get here.
Approximate times of working: 3:30 PM - 7:30 PM
Shooter
Today was not overly productive for the shooter mechanism, as most were working on continuing drive base stuff and working on the intake. As of now, the idea of using the "surgical tubing links haven't been discussed much further, as we have in general been okay with the way the shooter has been functioning thus far. All we are doing for now is improving the other mechanisms to reach to the same caliber as the shooter.
Intake
Today was a beautiful day for the intake. Finally, we added one side roller, consisting of a BAG motor (is a way a "Baby CIM", just a step down from the Mini CIM) and a Banebots wheel, attached a spare talon (talon is a type of motor controller) to the drive base, and wired the motor to the talon and talon to the power distribution board. While this took a while, we did get to test it (click here to get youtube video), and the ball flow was beautiful. This was much more effective than what we were expecting. Before the side roller, the angle of the ball going into the intake had to be within a 30 degree range. Now, we have an angle range of nearly 270 degrees. Our intake also went to working well for an 8" range, now to around a 56" range. The drawings below are not quite to scale, but is hopefully enough to get the point across visually.
Intake
Intake with ball projection without changes
Intake with ball projection with changes
As demonstrated on the one side in the video, the robot can now pick up a ball coming from behind the robot at an angle without getting stuck, and, basically as long as the ball touches any part of the intake, the ball goes in. This has signaled the detailed design process has already begun, as we had built a prototype that works, and are now just trying to improve the functionality of the intake.
Drive Base
The drive base today was worked on a little today, just primarily testing to make sure it works and functions reasonably decently, and adding extra parts (the talon for the extra side intake motors). Also, we almost finished the official practice bot drive base, and it's just a matter of attaching the bellypan with the electronics already mounted, as well as waiting for the 2nd set of 3 CIM single-speed gearboxes to get here.
Approximate times of working: 3:30 PM - 7:30 PM
Monday, February 17, 2014
1/23/2014 Day 19: Finishing Practice Bot Drivetrain
Since we got the drivetrain stuff yesterday, today mostly consisted of putting everything together, and worked a little on the intake. Being a Thursday, we left a little early today.
Shooter
Today, the surgical tubing arrived, so we got to begin to play with it. Although it was very thin, we observed this higher quality surgical tubing was still pretty great. After cutting the surgical tubing more than halfway, the tubing wouldn't snap when extensively stretched, and it wasn't until it was cut around 3/4 through that it started to rip the rest of the way. After playing around with the strength of the surgical tubing, we also tried to begin making the loops using a nut and bolt and soap to make it more easily go in, since the nut and bolt head were each larger than the hole, but they kept slipping out. Before we got to try a couple other methods, we had to go.
Intake
While it was figured out previously that we needed side rollers, the team went ahead and just tried playing with the intake one more time before adding side rollers. As happened before, the ball had to be hit almost spot on in order to be sucked up. While this was tested, the holding of the ball using the intake was also tested, and, happily, we found the current geometry of the intake perfectly held the ball in the robot very securely. Also, while the intake geometry allows the robot to keep the ball securely, the intake can also spit out the ball if needed, and spit it out around 10 ft. This shows the intake probably just needs the side rollers, then it'll be okay.
Drive Base
Today, the drive base was continued, and, after taking a very long time (we kept making little mistakes that would make us take apart everything, make the change, and put it all back together), we finished the drivetrain for the official practice robot. In addition to the drivetrain structurally being pretty much finished, we went ahead and laser cut a bellypan (flat surface that is the bottom/belly of the robot), and made sure it fit, and started placing electronics onto the bellypan. Primarily due to the drivetrain taking forever, this was everything we got done today for the drive base.
Approximate times of working: 3:30 PM - 7:00 PM
Shooter
Today, the surgical tubing arrived, so we got to begin to play with it. Although it was very thin, we observed this higher quality surgical tubing was still pretty great. After cutting the surgical tubing more than halfway, the tubing wouldn't snap when extensively stretched, and it wasn't until it was cut around 3/4 through that it started to rip the rest of the way. After playing around with the strength of the surgical tubing, we also tried to begin making the loops using a nut and bolt and soap to make it more easily go in, since the nut and bolt head were each larger than the hole, but they kept slipping out. Before we got to try a couple other methods, we had to go.
Intake
While it was figured out previously that we needed side rollers, the team went ahead and just tried playing with the intake one more time before adding side rollers. As happened before, the ball had to be hit almost spot on in order to be sucked up. While this was tested, the holding of the ball using the intake was also tested, and, happily, we found the current geometry of the intake perfectly held the ball in the robot very securely. Also, while the intake geometry allows the robot to keep the ball securely, the intake can also spit out the ball if needed, and spit it out around 10 ft. This shows the intake probably just needs the side rollers, then it'll be okay.
Drive Base
Today, the drive base was continued, and, after taking a very long time (we kept making little mistakes that would make us take apart everything, make the change, and put it all back together), we finished the drivetrain for the official practice robot. In addition to the drivetrain structurally being pretty much finished, we went ahead and laser cut a bellypan (flat surface that is the bottom/belly of the robot), and made sure it fit, and started placing electronics onto the bellypan. Primarily due to the drivetrain taking forever, this was everything we got done today for the drive base.
Approximate times of working: 3:30 PM - 7:00 PM
1/22/2014 Day 18: Setting Concepts in Stone and Continuing tweaking/prototyping
Today was a bit slower, as everyone was still getting readjusted from the long weekend and 20 ish hours working on robotics over the weekend. Also, there were looming deadlines beginning to appear, especially the Chairman's Award, which had not been worked on much at all, so around one-third of the people who were there were spending their time on the Chairman's award and a couple other things rather than the robot. While this did happen, a few things did get done with the robot.
Shooter
As we were all happy with the way the shooter was yesterday, we didn't do much work on it, but went ahead and ordered some nicer and more compact surgical tubing. We didn't get to find how much force the surgical tubing had on the catapult, but it did take a 210 pound person to basically put all of his weight on the catapult to push it down. While that isn't overly precise, that is the best measurement we took, since we didn't have any sort of spring scale to measure the force with us. In general though, we have an idea of how much force needs to be on the catapult, and can always either tension the existing surgical tubing or add more to increase the force if needed, which, of course, is the nice thing about surgical tubing catapults as opposed to other ones.
While this was the current idea we had, another idea popped up, in that it would be a good idea to use segments of surgical tubing with set lengths, so there is a more regulated and even tension/something that could be easily reproduced/recreated. The example brought up was with spear guns, and one of the mentors brought a loop of surgical tubing that used to be in a spear gun, where it was just a set length of surgical tubing and a double sided hook that went into both sides, which held it together as a loop.
Intake
Today the intake was not really worked on, as people were either further looking into the shooter, making models (not human ones) on Solidworks of the robot, working on the awards coming up slowly, and on the newly arrived kit of parts drive base.
Drive Base
Today was mostly the cutting of the drive base parts that just arrived today, since each of the pieces are 32" long, but our robot needs to be 23" on one side. Other than cutting everything down, nothing much else happened with the drive base today.
Approximate times of working: 3:30 PM - 7:30 PM
Shooter
As we were all happy with the way the shooter was yesterday, we didn't do much work on it, but went ahead and ordered some nicer and more compact surgical tubing. We didn't get to find how much force the surgical tubing had on the catapult, but it did take a 210 pound person to basically put all of his weight on the catapult to push it down. While that isn't overly precise, that is the best measurement we took, since we didn't have any sort of spring scale to measure the force with us. In general though, we have an idea of how much force needs to be on the catapult, and can always either tension the existing surgical tubing or add more to increase the force if needed, which, of course, is the nice thing about surgical tubing catapults as opposed to other ones.
While this was the current idea we had, another idea popped up, in that it would be a good idea to use segments of surgical tubing with set lengths, so there is a more regulated and even tension/something that could be easily reproduced/recreated. The example brought up was with spear guns, and one of the mentors brought a loop of surgical tubing that used to be in a spear gun, where it was just a set length of surgical tubing and a double sided hook that went into both sides, which held it together as a loop.
Intake
Today the intake was not really worked on, as people were either further looking into the shooter, making models (not human ones) on Solidworks of the robot, working on the awards coming up slowly, and on the newly arrived kit of parts drive base.
Drive Base
Today was mostly the cutting of the drive base parts that just arrived today, since each of the pieces are 32" long, but our robot needs to be 23" on one side. Other than cutting everything down, nothing much else happened with the drive base today.
Approximate times of working: 3:30 PM - 7:30 PM
Friday, February 14, 2014
1/21/2014 Day 17: A Breather
Today was the break after the marathon day, and consisted of mostly using it as a break and seeing if any teams created anything that may be useful to learn from. As a whole, most of the videos of team's shooters were just so-so, and mostly consisted of teams making shots from ranges between 9' and 14', but Team 842 (Falcon Robotics from Carl Hayden High School in Phoenix, Arizona) did release a video showing off a 10 second cycle and consistent shot from the same distance, which definitely changes strategy up quite a bit. This would mean they could score nearly 150 points on their own, which is more than 5 full 2-robot cycles. Judging from the video, a lot of previous strategy discussions will start becoming useless, and a lot of defensive strategies will most likely start forming.
1/20/2014 Day 16: Success!!! (again) and Affirmation for MLKJ Day
Today was the first of several weekdays of school missed by the team, but today is due to a holiday rather than a competition or lack of sleep. As the first marathon day (what most robotics kids call a holiday during build season) of the marathon of a build season, a lot was done and, as the title suggests, affirmation of concepts, as well as pleasant surprises.
Shooter Assembly
As the shooter was the main mechanism for scoring and getting points in general for this game, the shooter was worked on heavily today, with a positive outcome. After taking out the pistons, we put on the crude version of the tower (a large thing that sticks out the back to hold the surgical tubing) we made earlier, and started lacing the surgical tubing in loops around the top piece of conduit at the top of the tower and the catapult.
Also, we finally finished the winch (something that can drive something one way, but be loose when the direction of travel is reversed) (kinda like a motor attached to a ratchet). For the winch, we just used one of our two-speed gearboxes from last year, and took out a gear, so its two motions are forward and neutral. The gearbox has an axle in it that acts as a spool, and there is a strap attaching the axle to the catapult, so when the axle turns, it wraps the strap, again, similar to what a spool does with thread, pulling down the catapult and stretching the surgical tubing in the process. For today, we had the winch be driven by only one CIM motor, which is different, as we plan on using two Mini CIM motors (two mini CIMs has 30% more power than one CIM). Although we had less power, the winch didn't have much trouble with pulling back the catapult and latching it.
As for the shooter performance itself, the shooter had enough power to accomplish what we needed, with a straight-on view of the robot shooting here, and a video of its best shot here. The average shot (as it says in on the page with the video) was similar to the video, at 13.5' high and 33' away, which was fairly high, but solid distance. After changing the angle by elevating the back, we were able to shoot the ball nearly 40'. Even though this was fairly successful, we definitely could add more surgical tubing to increase power.
(For grins and giggles, we also shot the 2012 game piece, the foam basketball, which has a radius one-third of the big ball. Makes for one impressive shot, and that video can be found here.)
This prototype showed us the surgical tubing concept was definitely the way to go in terms of types of catapults/shooters, at it was just a matter of beginning to move into the detailed design process finally for the shooter.
Intake
Since most of the day was taken working on the shooter, the intake side rollers were only partially designed today, in terms of their position and their mounting. Other than that, not much else happened, since the shooter was the big event today.
Drive Base
Similar to what happened with the intake today, not much really happened for the drive base, since everyone was outside socializing and watching the shooter, although the new kit of parts drive train should be coming reasonably soon.
Approximate times of working: 10:00 AM - 5:00 PM
Shooter Assembly
As the shooter was the main mechanism for scoring and getting points in general for this game, the shooter was worked on heavily today, with a positive outcome. After taking out the pistons, we put on the crude version of the tower (a large thing that sticks out the back to hold the surgical tubing) we made earlier, and started lacing the surgical tubing in loops around the top piece of conduit at the top of the tower and the catapult.
Also, we finally finished the winch (something that can drive something one way, but be loose when the direction of travel is reversed) (kinda like a motor attached to a ratchet). For the winch, we just used one of our two-speed gearboxes from last year, and took out a gear, so its two motions are forward and neutral. The gearbox has an axle in it that acts as a spool, and there is a strap attaching the axle to the catapult, so when the axle turns, it wraps the strap, again, similar to what a spool does with thread, pulling down the catapult and stretching the surgical tubing in the process. For today, we had the winch be driven by only one CIM motor, which is different, as we plan on using two Mini CIM motors (two mini CIMs has 30% more power than one CIM). Although we had less power, the winch didn't have much trouble with pulling back the catapult and latching it.
As for the shooter performance itself, the shooter had enough power to accomplish what we needed, with a straight-on view of the robot shooting here, and a video of its best shot here. The average shot (as it says in on the page with the video) was similar to the video, at 13.5' high and 33' away, which was fairly high, but solid distance. After changing the angle by elevating the back, we were able to shoot the ball nearly 40'. Even though this was fairly successful, we definitely could add more surgical tubing to increase power.
(For grins and giggles, we also shot the 2012 game piece, the foam basketball, which has a radius one-third of the big ball. Makes for one impressive shot, and that video can be found here.)
This prototype showed us the surgical tubing concept was definitely the way to go in terms of types of catapults/shooters, at it was just a matter of beginning to move into the detailed design process finally for the shooter.
Intake
Since most of the day was taken working on the shooter, the intake side rollers were only partially designed today, in terms of their position and their mounting. Other than that, not much else happened, since the shooter was the big event today.
Drive Base
Similar to what happened with the intake today, not much really happened for the drive base, since everyone was outside socializing and watching the shooter, although the new kit of parts drive train should be coming reasonably soon.
Approximate times of working: 10:00 AM - 5:00 PM
1/19/2014 Day 15: Beginning of Week 3 and Time to Judge Prototype Robot
As yesterday the robot was modified based on what happened early in the morning, it was time to test everything again with the modifications. We pulled out the carpet (what the robot drives on at competition) and the wood/rope truss we made (didn't quite finish the wooden high goal yet, but fairly close to done) and setup on the docks, so we could test general mechanisms, and make sure everything works the way it is supposed to. Pictured below is the prototype robot with a couple students and a mentor.
Shooter
As can be seen (or not seen) in the picture above of the robot, the shooter takes up very little space, and cannot really even be seen from a front view, although the ball is currently sitting on it (the front of the shooter peeks out a little, but not much. After attaching the latch to pre-pressurize the shooter, the shooter worked much better, shooting around 18' on average, and had one shot of 20'. In addition, each of the shots went over the practice truss easily, and had the right height to score in the high goal (bottom of high goal is only 8" above the top of the truss). While this worked for now, we decided this was the best it could do, but that means it isn't strong enough for our requirement of scoring from the white zone in autonomous mode. Because of this, we decided the pneumatic shooter is not the way to go, and surgical tubing is much better, since adjusting power is a matter of putting on more or taking off more surgical tubing. Also, the maximum power for the surgical tubing catapult just depends on how strong the steel bar on top is, and the indicator of too much is the bending of the conduit.
Intake
Since we had everything out, we retested the intake with less coarse plastic, so more of it was in the middle. Unlike what we thought, that didn't do much, and just did the same as making a smaller intake, since the ball has to be picked up with the middle of the intake, so any ball that hit the side would not get pulled in. While this was somewhat disappointing, we came up with an idea of having rollers on the sides also. This would easily solve the problem of the ball getting rammed into the structure, as it would quickly roll the ball into the middle of the intake. To test the idea, the only things needed would be a small motor, a small wheel, and extra motor controller, so we were ready to start designing this by tomorrow, since the day was already beginning to end by this time.
Drive Base
As the drive base was now decided upon to be wide, we were just waiting for the new kit of parts to come in the mail. We wanted to keep this 32'x32' base together as something to test the intake and the shooter, then cut it once the other drive base is finished, and get the currently built one anodized. As of now, everything on the base works well, and there is space for mounting everything.
Catcher
Today was the first day in a while we worked on the catcher. As we already had the folding sides idea prototyped, we just had to build a prototype a folding out corners idea, which we did out of PVC pipe and PVC crosses. The difference in surface area was very noticeable, as the surface area of the robot frame with the catcher folded in was about a quarter of the surface area with the catcher folded out. This presents a huge target for other teams and human players to hit, at approximately 20 square feet, as opposed to the tiny 5 square foot 23"x32" area before. This shows the general concept can definitely work, and it's just a matter of figuring out how to mount it after everything else is mounted.
Approximate times of working: 12:00 PM - 6:00 PM
Shooter
As can be seen (or not seen) in the picture above of the robot, the shooter takes up very little space, and cannot really even be seen from a front view, although the ball is currently sitting on it (the front of the shooter peeks out a little, but not much. After attaching the latch to pre-pressurize the shooter, the shooter worked much better, shooting around 18' on average, and had one shot of 20'. In addition, each of the shots went over the practice truss easily, and had the right height to score in the high goal (bottom of high goal is only 8" above the top of the truss). While this worked for now, we decided this was the best it could do, but that means it isn't strong enough for our requirement of scoring from the white zone in autonomous mode. Because of this, we decided the pneumatic shooter is not the way to go, and surgical tubing is much better, since adjusting power is a matter of putting on more or taking off more surgical tubing. Also, the maximum power for the surgical tubing catapult just depends on how strong the steel bar on top is, and the indicator of too much is the bending of the conduit.
Intake
Since we had everything out, we retested the intake with less coarse plastic, so more of it was in the middle. Unlike what we thought, that didn't do much, and just did the same as making a smaller intake, since the ball has to be picked up with the middle of the intake, so any ball that hit the side would not get pulled in. While this was somewhat disappointing, we came up with an idea of having rollers on the sides also. This would easily solve the problem of the ball getting rammed into the structure, as it would quickly roll the ball into the middle of the intake. To test the idea, the only things needed would be a small motor, a small wheel, and extra motor controller, so we were ready to start designing this by tomorrow, since the day was already beginning to end by this time.
Drive Base
As the drive base was now decided upon to be wide, we were just waiting for the new kit of parts to come in the mail. We wanted to keep this 32'x32' base together as something to test the intake and the shooter, then cut it once the other drive base is finished, and get the currently built one anodized. As of now, everything on the base works well, and there is space for mounting everything.
Catcher
Today was the first day in a while we worked on the catcher. As we already had the folding sides idea prototyped, we just had to build a prototype a folding out corners idea, which we did out of PVC pipe and PVC crosses. The difference in surface area was very noticeable, as the surface area of the robot frame with the catcher folded in was about a quarter of the surface area with the catcher folded out. This presents a huge target for other teams and human players to hit, at approximately 20 square feet, as opposed to the tiny 5 square foot 23"x32" area before. This shows the general concept can definitely work, and it's just a matter of figuring out how to mount it after everything else is mounted.
Approximate times of working: 12:00 PM - 6:00 PM
Subscribe to:
Posts (Atom)