The Ohio State University Ri3D 2020

Hi everyone! We represent the FIRST® Alumni group at The Ohio State University and are looking forward to an exciting first year participating in Robot in 3 Days and providing valuable resources to both local teams and the ChiefDelphi community! We will also be competing at the second annual FIRST Alumni Collegiate Competition on February 2nd.

We have created our project team based on these specific goals:

  • Encourage continued involvement in FIRST , thus strengthening the presence of our student organization within the FIRST community by filling volunteer and mentor positions across the state of Ohio
  • Focus on prototyping, documentation, and strategic analysis to present to the FIRST community
  • Allow members to gain project experience and develop individual engineering skills

Twitch (live stream):

Constant updates, documentation, and whitepapers will be released throughout and after the 72 hours and will be provided on this thread and on our website. Let us know if you have any questions!


’Twas the night before kickoff…

Video created by @alexronnebaum. Footage shot at FRC 677’s workspace.

The live stream has now started on twitch! We plan to have the stream live and people working for the entire 72 hours.

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We recently finished our initial strategy discussion. The strategy is highlighted in the text below as well as in our initial strategy video! Please ask any questions on the Twitch stream or on this thread.

General Strategy

This season, we kept the principle of a simple, robust, and fast robot. These three ideas are so important to us because we prefer to be consistently good over occasionally great. Our strategy at-a-glance is to focus on scoring five power cells at a time to the bottom port of the loading bay. Additionally, we want to be able to spin the control panel to be able to advance to the next stage of scoring and activate the shield generator. We also plan to climb onto the generator switch and be able to level ourselves while we are on the switch to get the fifteen point level bonus. This general strategy allows us to do multiple things. First, we are able to be a very reliable alliance partner as we have fast and consistent cycle times. Second, we are able to keep the robot as simple as possible (KISS principle) since we are not planning to have any major actuated mechanisms. And finally, we are able to perform easy maintenance on our robot as a result of simple mechanisms.

Power Cell Scoring

We are focusing on scoring in the bottom port of the loading bay. The main discussion on this was about the time vs point values. We thought that we would be able to dump five power cells at a time into the bottom port but that, due to the space needed to add a shooter mechanism, we would only be able to shoot a maximum of three power cells at a time. Thus, one cycle at the lower port would give us five points (five power cells scored at one point each) while one cycle in the upper would only give us one point more (three power cells scored at two points each). We decided that the one point difference was not worth the added complexity and inevitable time needed to line up to shoot in the high port. Additionally, the target zone offers protection (G10) while we’re shooting whereas if we were to back up from the alliance wall to shoot, we would no longer be protected while we were lining up and shooting.

Control Panel Scoring

We feel that being able to spin the control panel in order to advance to the next stage and activate the shield general will be integral in achieving high scoring volume and low cycle time. In addition, being able to both spin the control panel the required amount to advance to the next stage ( at least three rotations, but no more than five - game manual page 28) will make us a more versatile alliance partner as we are able to complete more tasks. We also decided that being able to automate this task will drastically decrease our cycle times as we would be able to quickly drive up to the control panel and clasp on, then, in a matter of seconds, perform the required task for our current stage in match scoring.

Generator Switch Climbing

For endgame, we are planning on climbing, alone or with other teams, on the generator switch to receive the climb bonus of 25 points. Our big idea for the climb is to be able to auto level to be able to be very flexible when climbing with other teams. Additionally, we are planning on being able to adjust our position on the generator switch while we are already hanging so that if we are the first team to get on the switch, we will be able to maintain levelness while other teams climb on the generator switch. To account for matches where we might be the only team climbing, we have decided to go with a two-prong climbing system so that we will be able to climb in the center of the generator switch need be.

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Hey everyone! We’re having a a live update and Q&A session on our Twitch stream at 9:45 PM ET! Come ask questions!

Doing another live Q&A Session on our twitch along with updates at 3:00 PM today, so get your questions ready!

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Here’s our Day 1 recap!


We attended the PAST Foundation Kickoff ( alongside many teams from the Columbus area. At this event, we began by talking a little bit about our organization and how we can assist teams during our robot-in-three-days 72 hours build. Additionally, we spoke about how teams can request college mentors for their teams and other ways they can use our organization as a resource. After the challenge reveal we helped distribute kit-of-parts to teams and then headed back to the Center for Automotive Research to continue our strategy discussion.


Our strategy discussion took about two hours starting at 11:45 AM. First, we went through and listed relevant robot requirements and important rules so we could keep them in mind during our strategy discussion. Then, we listed out point values of every possible task in the game and the ways to accomplish those tasks. For example, there are many different ways to both pick up and score power cells. Listing out these possibilities enabled us to dive deeper into our strategy and make sure we considered all options before locking any down. After we listed out all possible ways of scoring, we started to discuss possible tele-op strategies beginning with what we wanted to do with the loading bay. After lots of discussion and point calculations (explained more in our strategy document), we decided to focus on low port. Additionally, we decided to build a control panel mechanism so we are able to advance to the next stages of power cell scoring. Finally, we are planning to have an adjustable climb so we are able to level ourselves out while we are already elevated on the generator switch.


We started prototyping by drawing different versions of mechanisms and discussing both if we have the time and resources to complete it. Almost all of our prototypes were finished in a matter of hours and we also performed some proof-of-concept demonstrations to test certain parts of designs without having to construct the entire mechanism. An example of this is when we were testing out our power cell intake. We constructed a sample bar out of ½ inch pvc and wrapped it in a pool noodle spiral so that it would passively center the power cells. A lot of our prototyping was proof-of-concept style in an effort to save time and resources.

Chassis Assembly

We decided to use the kit of parts chassis in order to save time and make sure that we could get designing with a solidified idea of what our drive base would be. We went with the six traction wheel drop center chassis. Originally, we were planning on using omni wheels in the corners of our design. However, we realized that we would have to re-drill a lot of our bearing holes and other mounting holes. After discussing this a little bit, we decided that it would be better and more time efficient to just use the traction wheels in the corners.

Intake Bar and Ramps

A lot of fabrication for the intake bar and ramp has been completed, pocketed, and even painted. We are going with a “tube” design with a bar roller that actuates outside of the frame perimeter approximately eight inches to collect the power cells from a range of approximately 25 inches with mecanum wheels to automatically center the power cells before they’re pulled into the robot by compliant wheels on the same axle. After the power cells are rolled into the robot, they are transferred up to the delivery system by poly-cord rails on a ramp through the center of the robot. Then, the power cells are held in the ramp by a pneumatic lever. When we have collected enough power cells and are ready to score, the pneumatic lever releases and a bar roller at the end of the robot shoots the power cells into the low port.

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Current CAD Pictures, it’s a work in progress! More to come soon! Check them out soon on Screen!


Live Q&A at 9:30 in the livestream at !

Here’s our Day 2 recap!

We have officially finished our robot, named “THE”!

The following documentation will be released throughout the next couple of days, so check back frequently:

[Video] From Prototype to Finished Product: Intake
[Video] From Prototype to Finished Product: Control Panel Spinner
[Video] From Prototype to Finished Product: Climber
[Video] Robot Reveal Video

[Whitepaper] Robot Resume (1 page)
[Whitepaper] Subsystem Memos
[Whitepaper] tOSU Ri3D Overview and Strategy Whitepaper

[Other] Full Robot CAD


Good evening! We’ll be releasing documentation daily up until next Wednesday (schedule can be found on our webpage). Our Robot Resume includes basic technical facts about each subsystem.

You can find a video describing our low port scoring Intake Subsystem in detail, from its prototyping phase all the up to to the finished product, below:

Additionally, we also presented our robot to nine local FRC teams in the Columbus, Ohio area on Wednesday, January 8 (linked is the Instagram post).


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Just a question.

Is this “The Ri3D made by Ohio State University”?
or “A Ri3D made by THE Ohio State University”?


Can you show some more videos of intaking multiple balls, and having multiple balls in your indexer near each other moving up the polycord ramp?

I really like the gate idea.

I hope this answers your question:



Yes! Prior to being able to access the field, we only had one power cell to prototype with, so we did not consider what would necessarily happen if multiple balls go through our intake. As seen in the video below, the polycord moves erratically, which directly influences the movement of the power cells.

However, this design can be improved upon in order to prevent the polycord from moving around erratically, such as creating some type of guard on both ends of the nylon rollers and creating a top plate above the polycord to maintain the same amount of compression throughout the intake.


Wow that is a great video. Exactly what people need to see regarding the terrible ball-ball interaction. I still really like the gate idea to have polycord slip when you want it to slip. If a team added a bottom side polycord it would help or fix the jamming and keep the same functionality

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So it’s “The”, Ri3D made by Ohio State University?

Also, it was great getting to hear from you at the 3324 event Wednesday!


Here’s our Control Panel Spinner mechanism in detail.

Alternatively, you can watch this short Instagram story clip of our mechanism in action:

This post summarizes all our documentation released so far.

Video documentation:

Written documentation:

We’ll be releasing a full robot CAD model by this Tuesday! Ask questions on this thread!