After kickoff, we jumped right into prototyping! We researched designs used by teams in years past to get a general idea of what we wanted our storage system to look like. After we found some good references, we tested out two types of systems; pulley and wheel.
We started by using belts to move the cargo, but quickly found out that the belts would not stay seated in their wheels. Then, we started using smaller black rubber wheels to move the cargo, which worked better. We ended by trying to connect the two rows of black wheels, and were close to getting it working.
We finished the fist prototype design and tested it to see how well it worked. We found that we needed to do some small tweaks like make the back board a little closer and move around the height of the wheels. We tested the capability of it by hand feeding two balls and out taking them as needed.
Today, our storage team worked extremely closely with intake in order to get the intake and storage to work as one mechanism. We mounted it 11" away from the bumper, and then we added Lexan in a curve following the trajectory in order to make the transition smoother. We attached the top two axles to belts and pulleys in order to make them move simultaneously and then tested intaking the balls up the storage. Our goal when intaking was to try to find a point that the ball jammed, in order to find flaws in our design. We discovered that the ball got stuck between the second intake axle and the first storage axle when we out-took the ball, so we put Lexan over that gap to solve the issue.
Since our storage and intake mechanisms were fully functional together, we decided that we should start planning for our actual storage system while shooter was still prototyping. First, we had to consider how our storage mechanism would be oriented in order to allow for the intake to retract into the starting frame perimeter. We figured that the simplest method would be to pivot the storage back at an angle into the robot and have the storage in that fixed position to allow for the intake to have enough room to fold back in. Our only concern with this method was that the storage might interfere with the hang in this orientation. From there, the cargo team and the hang team sent one representative to make a rough robot real-estate to give us an idea on the amount of room we had. While we were waiting, the rest of cargo began to consider other options, including spring loading the second intake axle so that it becomes flush with the first axle when inside the robot and folding the intake up, with the second axle being the pivot point. After dinner we verified dimensions and used those dimensions to create a shopping list so that we can get started on designing our storage mechanism.
After a team integration to get everyone on the same page, cargo joined as a group to assemble our prototypes in CAD in order to figure out how to retract intake and what angle storage/shooter will be in order to maximize space efficiency. We each made separate assemblies for each mechanism and then placed them in a drive base assembly. Once the intake, storage, and shooter were all in one assembly, we were able to properly constrain and align the mechanisms to what we believe is the most beneficial positions. By placing the storage 48.82 degrees from the top of the drive base and by setting the intake pivot point to the top of the storage, we were able to retract the intake into the frame perimeter. Tomorrow, we will try to assemble this complete cargo pathway using the tools in our shop and see if all of our dimensions are still accurate.
CAD Prototyping 1/20/22
today we started putting the robot together based on the cad model we made. we made the storage to spec as it is in the cad model and are planning to add the intake and shooter soon. we put the storage on a base mock up on a 26 by 28 frame of our robot.
CAD was redesigned to more accurately reflect what the mechanism will likely become. An adjustable bracket was modeled after one of our designs from 2017 and the top 2 axles of the storage conveyor were placed on this bracket for easy and quick adjustments to the mechanism. A new mounting bracket was started to better integrate the bottom axle of the storage mechanism as the pivot point and back axle of the intake.
Today, we made a mounting bracket for the second and third storage axle motor. We also examined the belts that we would need for the axles. Then, we began to look into where we will mount the intake pistons on the storage. We made a CAD model of the intake, storage, and shooter in one assembly to see how it all fits together and to determine where we will place the sensors.
We moved the wooden backboard of the storage back an inch so that it's 9.5 inches from the center of the rollers.
We worked on the storage assembly, then combined it with the intake assembly. Then we fixed an issue with the hex shaft length by creating a new part, and continued to adjust the combined assembly.
Today we continued trying to fix the storage and intake combined assembly, but didn't finish.
We fixed the assembly, and started working on connecting storage to the Lexan plate. We also started working on a piece to mount a camera on next to the motor on storage. Then, we worked on creating structural support for the Lexan panels because we discovered that the Lexan bends when subjected to the force of the cargo entering the system. We quickly realized that our support was too frail and long, so we decided to change it to a 1x1 tube connected to the storage by two support beams. These support beams have additional support pieces, attaching it to the drive base and stopping the Lexan from moving.
We made minor adjustments for the storage support and cleaned up the CAD. Then, we created a motor mount that simultaneously stabilizes the transition space between the storage and the intake. We continued to work on infrastructure; By making part of the Lexan support piece mounted to the drive base and the Lexan C channel connecter, we were able to stabilize the entire Intake/Storage mechanism to the best of our abilities. We put an arc in our motor mount to maximize room for the cargo available. We finished by making dimensioned shop drawings for all of our pieces.
We added the Storage Cross Brace to both sides, and made Harris shop drawings for them. We also removed the rivet holes in the Storage Lexan Connector. The Storage Cross Brace now has rivet holes on both of the flanged sides, and the length of the Lexan Support Piece was adjusted accordingly to fit within the Storage Lexan connecting pieces. We also made sensor mounting brackets for our beam breakers. We placed one in between the first and second stage of intake so that we can stop the cargo in first stage if necessary. We placed the second one right after the second second stage axle, so that we can stop the cargo before we preheat to shoot. The first beam break will also act as a ball counter.
Finalizing CAD!! 2/6/2022
Looking at our sensor mountings, we realized that the sensor in second stage storage was very close to the belts and pistons. Although it did not directly interfere with the beam break, we felt a little uneasy about mounting a sensor near so many moving parts. After consulting with our Cargo programmer, we made the decision to move the second stage sensor from the end of second stage to the beginning. This is the updated version of how our sensors will work: the cargo will enter through intake and into storage. Sitting on the edge of the first storage axle is a beam break. When the cargo breaks this beam, the ball is now considered to be at the end of first stage. This will allow for us to stop the cargo and store it in first stage. This sensor will also serve as our ball counter, mainly for auto purposes. Next, the ball will enter second stage, marked by two more axles. There is a beam break at the first axle of second stage. When the cargo breaks the beam, then stops breaking the beam, the cargo is considered to be in second stage.
The majority of storage work for today was spent making shop drawings and minor adjustments. We are hoping to start fabrication soon as we are now finished with the CAD assembly itself.
Shop Drawing/ Fabrication 2/8/2022
Today, we got to begin fabrication! We made minor parts, such as the axles, and then spent the rest of the time making shop drawings. Our shop drawing efforts are going great, as we are flying through most of cargo, which allowed for us to divert most of our focus to hang, which needs some assistance.
We assembled our Storage assembly!! Starting with the superstructure, we worked our way up. We even added the beam breaks at a 110 degree angle. We just have to add the first stage axle, the Lexan and then test!
The assembly was slightly adjusted because the bars were not parallel, the first stage axle was added, and the Lexan pieces have been made and mounted. The Lexan transition piece from the intake to the storage still needs to be attached, but otherwise the assembly is mostly done.
Rally in TWO DAYS!
The past few days, we haven't done much work to benefit storage, but did have to frequently move the axles to make room for the other mechanisms (intake pistons and shooter). Because we made the axles able to shift independently, this was relatively easy. Design wise, the only major things we have fixed is leveling out the axles, attaching the support beams, and attaching the Lexan ramp to lead into the storage from intake.