Force Sensitive Resistor

We were trying to use a force sensitive resistor (FSR) to detect if we have two minerals in our scoring mechanism. If there where two minerals in the scorer it would turn on lights so the drivers can see if they were holding two minerals easier.

We fond that the gold mineral was too uniform to be detected by the FSR if it was placed flat on the floor of Scorer. Then we tried putting the FSR on the left and right side wall which had the same problem. Then we put the FSR  on the back wall which could detect the gold mineral, but could not tell the differences between the two minerals types. (This is shown in the graph below) Then finally we put the FSR back to its original position but used a cut zip tie to prop up one side this allowed the gold mineral to deform The FSR.

Decision: We decided to use the final meted of using a cut zip tie to prop up the FSR 

TeleOp Smoothing

Our summer robot’s controls aren’t great. It accelerates far too quickly and it does’t allow for fine control. Our goal today is to make the robot easier to drive, building on our exploration of quadratics last week..

We started with a very basic linear teleop.

Our first attempt at drivetrain input functions

Our first attempt at smoothing was to apply a quadratic to joystick input.

Quadratic smoothing of drivetrain functions

This still accelerated too fast. We decided then to create a “slow” zone
in the first half of the joystick range that would always drive a consistent
speed.

Quadratic with a dead zone

This proved best. We could easily go fast when we needed to, and we
can easily turn and inch slowly when we need to. If we use a 6WDC
chassis this year, this will be our teleop drive function.

Ryan and Chase testing the drivetrain

Summer Chassis Assembly

Today we started assembling our practice drivetrain and coding a
teleop for it. Jonah taught Chase and Kristoffer basic trigonometry and how to program mecanum wheels. Chase and Kristoffer didn’t know how to use polar coordinates yet and our programming wasn’t very functional so, Jonah gave them a quick overview. Afterwards Chase attached new gear boxes on the motors and helped Emilio and Ryan assemble the drive train. They got the wood we cut out earlier, filed out the wholes for the motors, and fit the motors and bearings. After, Emilio and Ryan put the two halves together. Jonah tested a new language for programing the teleop, tested, and fixed issues.

Jonah teaches Kristoffer the trig he’ll need to program a drivetrain
Chase assembles Vex VersaPlanetary gearboxes

Summer Chassis Assembly

Last Saturday, we cut out our side panels and top panel out of wood for our “Summer Demo Robot.” Today we finally started putting together our robot using the cut-out panels. We found that using Fusion 360 easily allowed us to design a functioning robot. With this knowledge we were easily able to assemble one side pod this meeting and plan to assemble the rest in the following meetings.

Emilio and Ryan assembling side pods
Our first assembled sidepod

CNC Cut Chassis Sides

After fully completing the CAD Robot, we decided on reaching out to a
former Suit Bots alumni Brian because he invited us to use his CNC Machine to cut some of our various custom parts for our robot. He said we could come over on July 6th. Upon arrival, we wentover how to use Fusion 360 in a way that allows us to view a simulation on how the CNC Machine will cut the stack of wood and create our panels. After that, we uploaded the 6WDC file onto the machine’s program that allows us to send the information to the machine. After 2 ½ hours, we had cut out all our panels. After we cut them out we sanded them down to be more usable and proper.

Our first CNC milled part: a side panel for the 6WDC chassis

Finalized CAD Model For 6WDC Chassis

Today one of our new freshman members Andrew came in. We showed him around and taught him how to use F360. Additionally with Andrew’s help we finished the side panels and top design for the 6WDC chassis.
Now the top and side panels are now ready to be CNC machined.

Rendering of our summer 6WDC robot

Fusion 360 Tutorials

Today we met one of our incoming freshmen. His name is Kristoffer and
he was drafted out of one our local middle schools, Clifton. We also
found that he is the youngest Disneyland Rider on this side of
Anaheim.

We also began the engineering tutorials for Fusion 360. We watched
several tutorial videos before having to leave. Jonah found it
inconvenient that you cannot mate in Fusion 360.

Jonah and Kristoffer learning how to use Fusion 360

Budget Planning For Next Season

Today we worked on creating an outline for the presentation for our
local rotary club. The meeting will be on Wed June 13. The purpose of
the meeting is to start a mentor network for Monrovia Robotics. We
will also ask them to commit to cover some of the teams’ travel costs
(any of the MHS teams moving on to the World’s championship).

We discussed the budget for next year. We came up with likely sponsors
and how much they will most likely give us.

For our cost estimates for next season, we assumed that we would reuse
most of the parts on our past robots, which is why our listed robot cost
is so low.

Our potential sponsors and how likely we think they are to donate
Our budget estimates for the Rover Ruckus season
Our budget estimates and potential sponsors, legibly.

Post Worlds

Goals

  • Reflect on the Relic Recovery Season
  • Determine the team’s level of commitment for the Rover Ruckus season
  • Decide how many new team members to recruit for next season
  • Discuss summer schedule

Summary

The returning Suit Bots sat down for the first time since Worlds to collect our thoughts. We talked about whether we wanted to try to be competitive again next year after losing so many seniors (we do), and how we want to go about that for next year. Since LA is losing several qualifying spots to worlds (relative to supers), we’ll have to be more broadly competitive for awards than before (as opposed to concentrating entirely on the Connect award) which means more concentration on the notebook and outreach.

Our upcoming summer events are as follows:

  • 5/19 Monrovia Day demo
  • 6/6 Chamber of Commerce Lunch presentation
  • 7/14 Cal State Games in San Diego

During the summer, we’d like to pick up some new skills, Fusion360 and
CNC milling. We’re going to meet next Tuesday to do a F360 walkthrough
with Mr. Porter and will design several robots over the course of the
summer to get the feel for the software.

We also need to learn a more formal engineering design process. Two
weeks from today we’re going to go over NASA’s process and see if it’s
a good fit for our needs.