For the week before that, we want to focus on improving the robot. We know we have a solid, controllable drivetrain. It's slower than past years, but due to the characteristics of the field, this can be a good decision to keep its current configuration. It gives us the torque to push other robots and resist defense. We can accelerate quickly, which counterbalances speed boosts of other robots slightly. Plus, it's good for training new drivers. We also know that the lift system is good as well. We braced the lift so shaking is minute, It has a fast raise, it's very obvious when the lift is in scoring position, and we have enough torque to right ourselves if tipped. The arm also gives us the ability to turn into a wall bot if need be. We also know the intake is in good condition. It can slowly grab balls and It can grab balls while driving. We also know that our large ball manipulator grabs large balls
We do know that the robot isn't in optimal condition however. The robot can tip itself if the lift is raised past the mast. Moving the center of gravity forward shouldn't be too big of a deal. We can also install roll guards. The lift system also lacks the torque to hang. Our hanging prototype is built, but testing it is difficult with our members scattered. We also know that our large ball intake is fairly slow. However, we can engineer the large ball rollers to be wider apart. Another thing that hurts us is our large ball storage and funnel system. Currently, both of these systems aren't operational. The funnel system can't close well and the large ball storage doesn't fold down. Both of these additions sap at our motor power without contributing to the robot
But as I've said before, we want to focus on improving the robot in this last week. Because of this, we decided to improve the funnels system and the large ball storage. Both of these systems hold great promise. The funnels helps the robot score 3-6 additional points in autonomous and quickly score bucky balls from the middle zone at the cost of a motor. Also, the large ball storage gives us the storage capacity of 3 large balls. Not only will that speed up our scoring in driver control and skills, it gives us major damage control.
Today was mainly a maintanance day. We tightened up the bolts for the demonstration tomorrow. We also flipped the cortex to attach the usb cable more easily. The scary part was when we found out the lift couldn't raise. We still need to determine why this occurs. We have a feeling that the flipping tests damaged the lift. We doubt that we broke the motors because electronics didn't contact the floor, we knew all motors were plugged in, and we knew that our batteries were green. Chances are, the axle bent.
Today, we had a demonstration at Tampa General Hospital. We organized this demonstration early last month. At the demonstration, we brought the waffle ball shooter, the frisbee shooter, and the vex robot. We let patients drive our robot and score game pieces into gateway crates/ We also made it a game to flip the crates and obtain the ball. We talked to a few parents about the robotics team at Hillsborough High School. as well as the competitions we participate in. The demonstration did run into a few problems. We forgot the communication modules needed to run the waffle ball robot, and we didn't have an area to shoot the frisbee shooter. However, the vex robot went very well.
During the demonstration, we felt how difficult it was to control the robot for the first time. For example, we didn't realize how difficult it would be to grab the ball, align the ball, and score in a goal. We had difficulty maintaining lifting height and finding the correct depth with the drivetrain. Part of this was due to miscommunication from the team and part of this was due to single driver controls. The programmers programmed the controls differently from what we expected. Plus, in a competition setting, we want to use 2 drivers. By adding these changes, we can simplify our engineering challenge and gain an identical result. During the 10 minutes we had before the demonstration however, the drivers gained fairly fluid control over the robot.
From the demonstration, we noticed the robot had 3 critical problems: It wasn’t durable, the lift relied on elastic power, and the funnels collided with the drivetrain bracing. Screws fell of quickly, the funnels kept on popping out, the lift was angling and much more. Because of this, we swapped all of our keps nuts with lock nuts. From experience, we know that locknuts attach to metal a lot better than keps nuts. To keep the funnel from popping out, we applied a screw within the linear slides which lock against another screw. To improve the tower rollers, we attached another column of standoffs to increase the points of contact. We knew the lift relied on elastic power because the lift couldn’t raise. For the sake of the demonstration, we added extra elastic to help raise the lift. After closer inspection, we saw that our axle was bending significantly and our holes were rounded out. Since our pillow blocks and motors were loose, the axle started grinding into our rail, inhibiting my lift system. Because this was such a big issue, we had to take apart the lift system and reconstruct it with better materials. As for the funneling system, we noticed one of our biggest problems was that the gears didn’t mesh. The funnels operate through one motor, and due to the opposing/hugging motion of the funnels, we need gears to change the direction of rotation. The gears didn’t mesh because the gears were cantilevered. So because of this, we started adding a plate which would squeeze the gears into place
Game pieces finally came in!!(only took them a month >.>) The primary focus of today was the lift system, intake, and funnels. Half of the team worked on rebuilding the lift system, a quarter worked on the intake, and the remainder worked on the funnels. The lift system was dismantled more, and the team worked on modularizing the system. We feared that the strain of competition could damage our lift and as a result, we would need new axles. So, we mounted our motors on 1x25 bars and used standoffs to attach to the gear tower/mast. That way, we can unscrew the 1x25 bars and reinsert motors or axles. Unfortunately, we didn't have access to many of our photos and the photos we did have were poor. This made reconstruction a lot longer than it should be. Also, due to the double motor design, single tower orientation, and our lack of pieces, we need to make custom axles. Meanwhile, we tested out the intake with the official game objects. Results came out a little better than expected. We thought game objects would react almost identically to our gateway tests. However, we could grab balls slowly pushed in, grab balls against walls, and we could grab balls racing towards the robot to an extent. Which is better than our gateway results. The main downside however is that balls have more difficulty going into the storage. Many of us believe it's due to the lack of ramp, however our mentor is suggesting that we keep the intake the way it is. For now, we'll stick with the intake, however if time frees up, we can improve the system. Also, since consistency within the funnels were a problem, we worked on that as week. We attached a 1 x 25 bar, linking the gears. Thanks to this, the gears don't skip anymore. However, the funnels still sag and catch on our drivetrain. To fix this, current ideas include reinforcing the joint, counter weighing the funnel, and using elastic to force the system into the desired position
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