It showed up as .stp.txt to me. I renamed it .stp and it worked.
I loved your robot this year. I have to say it was one of my favorite tall shooters this year and an elegant intake to boot.
Thanks for these resources and I look forward to seeing you in the future.
I’ll be rifling through the CAD later, but for now:
What changes were made between the wooden prototype and the real bot? Specifically, did anything perform significantly better or worse on one version? Was the wooden prototype better in any areas?
Will you be bringing the prototype bot to any offseason events?
How were you able to construct the prototype so quickly!?
Can I ask how you decided what locations on the field to shoot from? While most teams selected either the batter or the Outer Works as their primary shooting location for protection, you tended to set from a variety of unorthodox locations in addition to some of the more common ones.
I’d love to hear the thought process that went into deciding those, or did those come after the robot was already functioning?
I’m counting 15 medium sized BB wheels for each roller
At $2 each for bulk purchasing that’s only really $30 with probably $5-10 worth of spacers if using VEXpro ones
If you look at a decent alternative such as 1.5” OD Latex tubing stretched over an aluminium tube, you are probably going to be looking at $20-30( depending on what length you purchase) just for the Latex tubing, and $5 for the Al tube so there isn’t much of a price difference.
Plus a ½ hex shaft is much easier to interface with other COTS parts
After analyzing the game during the first weekend of build, we realized that there was only one protected zone - the outerworks. We also realized that shooting from the outerworks would be tough to do if we wanted to maintain a 95%+ accuracy rate which we set as one of our criteria. Therefore, we ensured that we had a multitude of locations to shoot from regardless of any defence being played.
Our primary shot requirement was the batter shot and the just off batter shot, where we would sit off the batter and shoot. We felt that this shot should be our primary shot because we would be closer to the goal, thus also increasing the accuracy of the shot.
Our secondary requirement was to ensure we could shoot from where we liked to call the “spy” box. It was in the far left corner of the courtyard where we could press up against both the side rail and opponent wall to shoot from. We did not use this shot come competition much but we felt like this shot would be slightly more accurate than the outerworks shot because we could not be moved once in that location and it was slightly closer than the outerworks.
Finally, our third requirement was to shoot from the outerworks. This was the last requirement because its distance to the goal was the farthest (and subsequently the hardest to nail).
Combining these shot ranges, we realized this allowed us to shoot from nearly anywhere on the field after doing some calculations and building the prototype. To ensure a higher degree of accuracy we designed a fixed shooter angle with only speed as the varying quantity. Our “diamond plate” shot became our most effective, but in reality it was the same as the just off batter shot. The turret just helped adjust for the angle difference.
TLDR: Shot locations were decided based on accuracy (the farther the shot location, the less accurate the shot would be). In addition, the turret helped increase our shot range.
That is an excellent prototype! I can see how you had one of the best robots in the world this time around. Out of curiosity, which week did you have that prototype completed?
This robot is so beautiful! What a great resource, thank you so much for posting this.
Very nice! You were fun to compete against in North Bay - tough competition, but if we had to get knocked out of the semifinals, at least it was by the best ones there!
Would you be able to explain the timeline you guys went through to produce your prototype robot so quickly? How many people were involved with prototype CAD? 8 days seems incredibly quick to turn out a fully working prototype (none the less a fully competitive one). Great work, one of my favorite robots this year!
The prototype was completed by the end of week 1.
Day 1 :
- Read/understand the rules
- Scoring analysis and determine game play strategy
- Outline clear needs, wants and wishes for what the overall robot should include.
Day 2:
- Determined detail requirements for each sub assembly of the robot
- Broke off into groups and brainstormed various ideas for each sub assembly
- These ideas were presented and voted for. Ideas with the most votes are prototyped
- Parametric analysis is conducted
Day 3-4:
- CAD prototype - About 10 students were involved in this, 2 students per subgroup (drive, intake, conveyor, popper, shooter).
Day 5-7:
- Build prototype
Day 7-8:
- Test Prototype
In order to survive the first week, we included things to look forward to such as a mentor vs student dodgeball game at the end of the first week. We also ensured the students had different food to eat every day when they came in (aka, not just pizza) - they were quite happy about this. 
The team I was on last year made it a point to enlist parents’ help to provide team meals during build season. Each family would sign up for a different night in rotation. We really enjoyed having a different hot meal each night, and we saw lots of cultural diversity represented: butter chicken, stir fried noodles, pulled pork, perogies, lasagna, pasta, …
We also discovered that gathering everyone together for a meal was the perfect time to do team meetings and status reports. We didn’t do the meals this year due to the nature of our build space, and we really missed that team touchpoint.
+2. We did the same thing and it was great.
There weren’t any significant changes we made between the prototype and the real robot. The prototype was designed and constructed with the purpose to ensure the mechanisms all worked consistently and cohesively together. That meant that most of our mounting/pivot points which were set on our prototype directly translated over to our real robot. Some big differences were we did not power the drive and the intake arm on the prototype as it was not worth the time, effort and resources to test. These aspects did not necessarily require an accuracy test and we have had enough experience to know we could power them in the final design. Some minor changes included the intake arm being one straight extrusion on the real robot versus the multiple extrusions used on the prototype. We realized we could use the lexan “fangs” above the front of the intake on the real robot instead of using multiple extrusions to achieve the same purpose (to pass through the portcullis while clearing the shooter head as well be able to do the drawbridge), leading to less weight and complexity. Also, the shooter was repeatedly revised on the wooden prototype to confirm our calculations and various tweaks were made to give us the 97% accuracy. That was the prototype we worked on extensively as that was where majority of our points would come. In the first revision, we messed around with the different wheel configurations/ number of wheels to ensure enough exit velocity was being achieved on the ball along with the correct exit angle of the shot. The second revision was a more refined version of the first as at that point we had locked in the combination of stacking 3 urethane wheels 4" in diameter with a 2" pinch as the ideal shooter configuration. We further tested using this configuration and determined our set shooter speeds. Finally, our third and final revision was simply our second revision with a better choice of materials for robustness and durability. We used denser material on the shooter head and beefed up the gearbox by making minor changes like using round bearings vs. hex bearings. This final shooter on the wooden robot is what ended up on the real robot. As for the conveyor, no significant changes were made other than reshuffling of the number of belts required and using banebots on the axles running the belts. Overall, our prototype was extensively used to translate the exact variables from the wooden prototype to our final robot. This meant we strictly used the parameters we discovered from our prototype to the real robot.
The real robot performed better in all the aspects, but not significantly as we repeatedly revised the prototype to the point it could be used as a functioning robot. Our goal was whatever ends up on the real robot HAD to be tested on the prototype.
Our final robot was as good if not better in all areas than our wooden prototype due to the reasons listed above. One feature we decided not to keep for the real robot that was in our prototype, was a pusher bar to expel the ball from the shooter bowl into the conveyor. We decided not to keep this feature due to its lack of usefulness vs. requirement of weight.
Unfortunately, we have disassembled our prototype as we used some of the parts on the real robot, so we will not be bringing it to offseason events.
Take a look at our prototyping process which Jash has outlined above. Following this process religiously is what led us to construct the prototype so quickly.
After testing with different materials, we found the banebots to be the most reasonable solution. We initially started by obtaining custom rollers from a sponsor with a urethane exterior and a harder abs core including a hex cutout extruded through. We found this to be quite heavy compared to the banebot spacer combination. Furthermore, after extensive testing we found that the banebots actually gripped the balls a lot better and did not stall the the rollers at all. We were worried about the wear of banebots throughout the season but the pros outweighed the cons significantly. Fortunately, we did not have wear issues with the banebots either. You can actually see we have used the orange urethane rollers on our practice robot.
I’m curious to hear how you manage to make the CADing and prototyping proccess so fast, but yet very effective?
The way I see it, deciding to forgo the low bar must have saved you folks a lot of time in coming up with a prototype so fast.
Your robot along with 3476, 2481, 368 who we played with in Hawaii, etc. proved that the tradeoffs between tall robots and having to go under the low bar were non-existent.
This was a great tall shooting robot. Thanks for sharing.
This is such a beautiful and thorough example of effective prototyping, and putting in exactly as much effort as each subsystem requires in order to be effective. Everything on the robot was prototyped, but the systems that required more attention got it and the systems that didn’t were kept simple and quick. If more teams prototyped like this, the entire league would be so much more competitive and inspirational. Thanks for setting such a great example and putting your work and process out into the public eye like this.
Better than 2013? Great season, look forward to seeing what you guys do in the future. Awesome robot this year, we had fun with you on Newton - well deserved 1st seed.
I would love to have a copy of your code mostly for the vision tracking part.