Day 6 – Mail! (1/9/2020)

Authors: Andrew Georgioff, Ritik Mishra


Unfortunately, progress was a little slow compared to the other days due to other meetings (FTC mentoring, mentor meeting, SW Hub meeting).

We did, however, get a bunch of parts in the mail, including

  • Spacer stock for the drivetrain
  • Metal parts for our 3D printed vectored intake wheels
  • A lazy susan for our turntable v2

There will be a prototype design review meeting on 1/10/20 at 7PM. Be there or be square, because you won’t be around. 

3D Printed Vectored Intake Wheels

The following blog section is brought to you by Stratasys, because they 3D printed a bunch of parts for us. Thanks, Stratasys! 

Today we received the 1/16” dowel pins and thread-forming screws in the mail to make the 2 inch vectored intake wheels. Vectored intake wheels are a special kind of wheel (also called mecanum wheels) that have rollers at a 45 degree angle to the wheel’s axis of rotation. When used on ball intakes, these rollers allow the ball to center itself relative to the robot.

Above: A video demonstrating the centering effect of vectored intake wheels
Above: A picture of two vectored intake wheels we assembled today

 We drilled out the center of all of the rollers to fit the dowel pins. We also figured out the specific order in which parts had to be assembled so that they would fit together properly even though there are no specific assembly instructions. Tomorrow, we will likely assemble more wheels now that we have all of the necessary parts prepared.

Above: A picture of all of the parts we have received from Stratasys so far

Sgt Sammy 

Thanks to the effort put in by the programmers, Sgt Sammy is now operational! We checked the encoders, and they definitely give readings, although the accuracy of their readings have yet to be verified. We will need to adjust the readings since the encoders have recently been demonstrated to sometimes show a red light (indicating that the readings will not be very reliable).

Next steps include testing the accuracy of the encoders, fixing their mount so that the readings are more reliable, and figuring out the inherent properties of Sgt Sammy’s drivetrain (e.g max acceleration, velocity feedforward, etc).

By the way, since it does not seem to have been mentioned before, we are using the SRX Mag Encoder sold by CTRE.

Double Flywheel

The double flywheel prototype has had some improvements today. We added gears and a belt to connect the two shafts together instead of running them both separately. This change also will enable use to test this design with the NEO brushless motors, which we hope to test tomorrow. 

Quote of the Day: “Plug and play on Talon Robotics means plug it in and go play outside for 4 hours because it won’t work” — Isaac Ash-Johnson. Senior Engineering Captain trying to debug a plug-and-play system