Objective: Repair the lift's bending axle from competition + make some progress in other areas
Tasks: Insert the linkage support and flat bar support to prevent axle from bending by distributing load towards other parts of the robot. Replace bent axles. Work on de-scoring system. Work on code
Problems: Using the linkage support will prevent the chain bar from going behind the robot. This prevents us from doing the wall-bot strategy, and due to the characteristics of a chain bar, we cannot hang.
Solutions: Take advantage of the chainbar support to limit max raising height, making it easier to score buckies. Improve autonomous so we do not need the wall-bot strategy. Use other means, such as de-scoring, to make up for the inability to hang.
Today, the attendance was low for vex. Because of this, we siphoned a few members from the programming team because programming isn't needed immediately. With this flux of members, we broke into 2 main groups. One group worked on repairing the lift, the other group worked on the de-scoring system. Before the lift team started on the lift, the took the parts they needed from the FRC intake prototype. This prototype had the new, long axles they needed to repair the lift.The team then developed a linkage support made from a piece of steel C-Channel trimmed to 5 inches long. We chose this length because we didn't need something long. The short length was compact, readily available, and useful at bracing the lift system. To repair the lift, we had to take it apart. We took advantage of the modularization and speedily took off the motors. Then, the tower itself was carefully disassembled. We took 2 pieces of 1 by 25 bars, and trimmed it to 7 holes. This new hole length will encapsulate the bottom 3 axles. We could not surround the top axle because of spacing issues, which would soon lead to frictional issues. The tower was not reconstructed yet. Meanwhile, 2 members from the programming team started developing the de-scoring system
The de-scoring system is a bendable fork which enters the column goal and folds in one direction. When it enters, it folds into a small area, however when the fork is raised, it should pull about 2 buckies up. To create the system, motor power is shared with one of the intake rollers. A sprocket will run from underneath the roller, which leads to a larger sprocket that powers the de-scoring system. This gear reduction helps add the torque needed to de-score, and the range to allow the intake to grab during competition. Anyhow, this larger sprocket leads to a set of beveled gears, changing the direction of power. That 90 degree change then allows the robot to raise the fork up and down.
The de-scoring team was guided by a CAD model. The team found parts which mimicked the model, and used it to construct the system. The main exception was that the real system did not use a long angled bar, rather a scrap piece to minimize weight. After the system was built, a few problems arose. For one, the model was built too compact. Some conflictions arose. Another problem was that the beveled gears didn't mesh completely. It's uncertain whether it was due to the bent angled bar, or a possibly bent axle. Because of this, the model didn't have the same range of motion as it should have, and it couldn't raise past the sprocket without gears skipping
Objective: Complete De-scoring system, Reinforce lift, and improve code
Problems: De-scoring system’s beveled gears skip, and there are collisions between pieces. Lift axles are twisting. Code does not accomplish all tasks within the 15 second period
Solutions: Rebuild the beveled gear mount, use new axles, and rebend metal back into place to fix the de-scorer. Install the linkage support and 1 by 7 hole metal for support. Combine tasks to minimize steps and use limit switches to shave time.
Tasks: Rebuild mount, bend metal, install gears on linkage, and format the code
Today we worked on the De-scoring system, Lift, and Code for next competition. Our competition is on February 8, which is 8 meetings away. We concluded that if we maximize on our bucky balls, large balls, and autonomous, we can formulate an effective strategy in programming skills, robot skills, and qualifiers for another excellence award, while building sufficient synergy for states on March 1st. We took the same concept of automatically starting at the start of the match from last code, and sped up the wait codes with a limit switch. Thanks to this limit switch, we can trigger the next sequence of code without waiting for a timer value to go off. In addition to this, we sped up the code by removing unnecessary decelerations and combining the step of expanding the robot and backing up. With this, we can shave a few seconds of time from our autonomous program. For the lift system, we added 2 gears to the linkage support to get a bit of progress in that area. For the rest of the meeting, we hashed out the de-scoring system. We knew from last meeting, the beveled gears skip. Because of this, we closely analyzed the mounts of the beveled gears. Because the mount was re-bent into place, the beveled gears didn’t mesh completely. We took a trimmed angled bar, and trimmed it further to a 2 by 3 hole angled bar. Because this angle bar wasn’t bent, the gears should mesh better then the last mount. After making this mount, we realized holes didn’t align with our current design. Because of this, we had to reposition our pillow blocks, allowing holes to align. After the holes aligned, we then tested out the system. We realized there were collisions between the de-scorer’s mounting screws and the rail. However, we noticed the rail was bent to an irregular position. We bent the rail back to the factory position the best we could, and eventually, the de-scorer had the clearance it needed. After this, we worked on the de-scoring fork. We placed locknuts to hold the forks in place, but we slightly loosened the pieces to provide a stable connection with smooth motion. We also attached a standoff to the back of the fork connected to rubberbands. Thanks to this connection, when the bucky balls push the fork, the fork will bend, but when the ball completely passes the fork, the fork will flip out completely, latching onto the balls.
We also ran a quick test with chain. We looped 1 round of vex chain around the FRC intake. We placed it on a hanging bar, and we found out that chain could hold the intake. This indicates that we might be able to hang with a chain bar as long as we do not turn the chain too much from a far angle
Objective: Continue reconstructing the lift, Continue constructing the de-scorer, Finish up the new autonomous program
Problems: Mismatched holes on the lift, Inserting chain, minor errors in code (not having a properly named pragma, using mindstorms robot C not cortex)
Solutions: Move the lift accordingly, practice putting in chain, renamed pragma appropriately, changed robot c version from mindstorms to “cortex 2.0”
Tasks: Screw together lift, cut metal, chain the de-scorer, apply rails for de-scorer, make the code trigger the next stage with a touch sensor.
We’re continuing to optimize on bucky ball and large ball abilities with the lift system, de-scoring system, and autonomous program. For the lift, we need to fix the axle bending problem between the 2 60-tooth gears. To do so, we mounted the linkage support onto the gear tower. However, writing this now, I realized we forgot to insert metal strips of 1 by 7 metal bars to support the axles. The linkage support assists the axle by splitting power to the 60-tooth gears. That way, all the force does not transfer through the center axle. The 1 by 7 bar will support the axle by transferring any force to the other axles. We made these 1 by 7 bars by cutting the 1 by 25 bars to dimension. In addition to this, we’re copying the support we had previously. We’re placing a standoff adjacent to the bending axle adjacent to the bottom most axle. That way, we can support the bottom axle for the future incoming forces.
As for the de-scoring system, the main problem we have now is supporting the de-scoring fork. Because the fork is mounted on chain, the entire fork has the tendency to rock back. To fix this, we added guide rails to slide against the structure of the de-scoring system, limiting how much the intake can slide back. A freshmen was assigned to do this job. Naturally, they had issues installing chain. Because of this, we guided them through the process, and gave them repetitive tasks to help build up their skill. Now that this is compete, we need a way to test the mechanism. Because of this, we need to construct a goal soon.
For autonomous, we started developing code which would progress when a person triggers a touch sensor. By doing this, we can cut down seconds of time on our autonomous program. To do this, we created an integer called “burst”. With this integer, we can trigger a series of while loops as needed. In English, with this number, we can trigger autonomous sequences as needed. The interger, burst, is set to 0 at the start of the match. Because of this, the first stage of code will run automatically. However, at the very end of the code code, we placed an additional while loop. It’s important to have a while loop inside of a while loop because you don’t want the code to repeat to the beginning like it does with a single while loop. By adding this while loop at the end, you prevent the code from completing, and thus repeating. Within the while loop, we inserted the last bit of code we want to run continuously. Usually, it was just set all motor power to 0, and an If statement. By setting the power to 0, the driveteam can orient the robot as needed. The if statement is critical however, because since the code is stuck within the while loop, the robot will only receive commands from the while loop. With this if statement in the inside, we can push the touch sensor, changing the burst value, and thus, changing the while loop. We can then use this next number to trigger the next sequence within the code. As for the actual code, We broke the autonomous program into 4 stages.
Stage 1: This occurs at the very start of the match. The robot backs up as fast as possible and raises the lift to get in position to grab the bump buckies and expand the robot to size. Once in position, the robot opens up the funnels, and power is cut to the lift system. This gets the robot to ready to grab bucky balls, and lowers the lift. The robot then drives forward as fast as possible and uses the funnels to push Bucky balls into the grabbing intake. Meanwhile, the lift is slightly powered down to prevent the lift from raising. The robot continues to drive forward and closes the funnels. From there, the human driver can help guide the robot to grab bucky balls against the field perimeter and reorient the robot towards the first large ball. The switch is pressed to go to the next stage of code
Stage 2: The robot drives forward and raises lift at the same time. The robot decelerates slightly to avoid damage to motors. The robot drives back to the alliance tile, but maintains lift height with slight power to the lift. The human player reorients the robot to the second large ball and triggers the next line of code with the switch
Stage 3: The robot drives forward and hits large ball. It decelerates to avoid motor damage and it returns back to the alliance tile. The human player reorients the robot the column goal to prepare for a bucky ball stash
Stage 4: This stage may vary based on time. The robot has a delayed acceleration with varying power values to avoid wheel slip. The robot gets close as possible to the goal, raises lift, and drops all 3 bucky balls into the goal. The robot then backs up to prepare for driver control
Now that the code is written, the robot needs to be rebuilt to test it.
We also looked at a few flaws of our engineering notebook. Last competition, we found out from the judges that we had a slight advantage then the other teams in the excellence award. Because of this, we want to optimize on what we’re good at. This may increase our edge even more, and it may help guarantee our chances for the design award in the states competition, which can advance us to worlds.
-Budget doesn’t show fundraised amount
-Budget doesn’t show amount of recycled parts
-The about us is Lacking
-Add a Quotes Page
-Add photos to Fundraising Page
-Elaborate on material list
-Update events (end of fundraising)
-Thanksgiving break meetings
-exam week meetings
-Describe the strategies in the strategy page
-Add tabs signifying competition days
-Add newest code to programming page + Explain
-Add to community outreach page
-Add a Section just for CAD
Objective: Fix the Gear tower, Continue with the de-scoring system
Problems: Getting the right spacing to minimize wiggle room of gears, the de-scoring system mount was too short. Lots of resistance on the gear tower
Solutions: Spend a lot of time carefully adding spacers, elongate the mount for the de-scorer, loosen lock nuts, and replace bad gears
Tasks: Rebuild the gear tower, add spacers, mount gear tower,
Today, we focused on finishing up the gear tower with an extremely high build quality. We first added the metal strips we forgot last meeting. Using these strips, the axles can’t bend past a specific point. In addition to this, we carefully added spacers to ensure the gears would mesh perfectly. After about an hour of attention, 2 of the axles were perfectly spaced, while the remaining 2 had gaps of less than a quarter inch. Moving on from this, we moved the gear tower by hand. Shockingly, we noticed there was a lot of resistance. After closer inspection, we noticed 2 main things contributed to this problem. The first problem was that the top left gear was chewed up. The damaged teeth explain why there was heavy resistance in some places and not in others. After we swapped out the gears, resistance became much less. The second thing we realize was that the lock nuts on the linkage were quite tight. Because of this, we loosened the locknuts, allowing the linkage to rotate, reducing friction greatly. As time went on, we also realized the holes didn’t perfectly match up. Because of this, we can guess that the axles we are currently using are slightly bent. After fixing a majority of the frictional issues, we started working on the intake and de-scoring system. We tried mounting the de-scoring system onto the intake, but it’s mounting bar was too large. Because of this. We had to swap out the mounting bar for an 8 inch rail. We used that rail to mount onto the side of the intake system. After mounting, we realized how bulky this system is. Because of this, we need to make more modifications to the mounting system to make the de-scorer more compact, and thus more stable. Currently, we can slide the de-scorer on the mounting bar a few holes, shrinking the width of the system by a bit over an inch. To power the de-scoring system, we placed a 6-tooth sprocket underneath the right intake roller. This creates a gear ratio for 3:1 torque, giving the driver large tolerance with grabbing, and high torque for de-scoring.
On the side, we think we know how to create an optimized robot for worlds that can manipulate buckies, large balls, de-score, and hang, but we plan on modeling out the robot first to see if dimensions work well.
Objectives: Work on intake, Finish Lift, repair the funnels, work on de-scorer
Problems: Large lift slop, bowing in the tower system
Solutions: Add counterweight to one side of the lift, reinsert the tensioners, mount braces, fitting into dimensions
Tasks: Move rollers to appropriate heights, mount braces to the lift, chain the chain bar, tweak the de-scoring system, reinforce the funnel system, retension the chains on the funnels, reduce the size of the de-scoring system
Today, we worked on 4 things: the intake, funnels, lift, and de-scorer. For the intake, we moved the left roller down to match the height of the other roller. Meanwhile, we added a strip of metal to the motor mount on the funnels system. Thanks to this, the axles on the axles do not bend the mounting plate. This added more tension to the system overall. For the de-scorer, we noticed that the weight of the system is causing the arm to bend to the right. Because of this, we did our best to bring the system closer towards the intake roller, minimizing torque and thus weight. Despite this change, the system continued to bend. We also tried fitting the system into dimension. Unfortunately, it makes us out of dimensions by an inch. For the lift system, we rechained the lift and made the intake angle as short as possible. We then tried adding tensioners, but one of our members got injured by bending an axle and nearly blacked out due to a vasovagal attack. The member was told to sit down, drink water, and eventually lay down with his feet elevated. He recovered soon after.