Roller Claw Update - Power!!!

By Fernando

Over the past few weeks we have been working on getting V3 of our roller claw, now forever to be known as Speciminer, into working order. V2 of Speciminer worked well enough at intaking but could not eject or tell if we collected the correct sample color. Additionally, while V2 was sturdy enough, it likely would have failed in some capacity after just a few times of us using it for testing or practice.

What's New:

• Color Sensor
• Dyed Rollers
• Carbon Fiber Braces
• GoBilda Super Speed Servos
• TPU Belts

To optimize strength and speed we had to make a few changes to the parts we used. Our new braces for the claw halves are made out of 3mm carbon fiber and mix the geometries of both the old CoPa (Nylon) braces and the aluminum servo mounts. This was done to increase the strength of the braces and remove the extra bulk and weight added by the aluminum brackets. We replaced the REV servos with GoBilda Super Speed servos to increase intake/eject speeds and decrease cycle times. We decided to go down this route as even mere seconds can be the difference between a win and a loss.

Something that V2 of Speciminer was not equipped with was a color sensor. Being able to detect a block's color does not affect specimen scoring, however; having it will make cycling samples a lot more efficient.. Speciminer's main purpose is to score specimens, but we would still like it to be able to manipulate samples in case something goes wrong with Sampler (our sample intake system). Because of this, we redesigned the tip of the center aligner to house a color sensor that sat flush against its outer wall. Unfortunately, due to the sensor's position directly adjacent to our *red* Ninjaflex rollers, Speciminer became basically useless once our auto stop/eject program was implemented. Because the sensor would constantly read red the automatic stop was always enabled while on Red alliance. While on Blue Alliance, the constant red reading would lead to continuous auto ejection. Because of this issue, we decided to dye our rollers a different color using black Rit liquid dye.

What Went Well:

• Color Sensor
• Carbon Fiber Braces
• Super Speed Servos

After off-robot testing, coding, and tuning, we've gotten promising results. Once we resolved the red ninjaflex snafu, we could write and properly tune code that automates Speciminer's functions. Adding the color sensor has allowed us to automatically stop intaking once the correct color has been detected and automatically stop ejecting once no sample/specimen is detected. Additionally, Speciminer is now able to automatically eject a sample/specimen of the wrong color and automatically start intaking once it is no longer detected. The switch to super speed servos has made the rollers and the overall intake speed significantly faster than that of V2. The 3 mm Carbon Fiber braces are much stronger and will last for way longer than the 4mm CoPa braces of Speciminer V2. Plus, they look way cooler :>

Plans for the Future:

While we've done some off-robot testing Speciminer still has a lot of trials to undergo before it can be certified and ready to go. The next step will be to put Speciminer on either the robot itself or a test rig that simulates almost the exact same conditions as our current robot. This step is being done to see how it will interact with specimens and samples while on a linear slide arm. Once it's on the robot, we will focus on getting it to work primarily with specimens during both auton and teleop. After that, we plan to make sure that it can work in sync with Sampler when trying to manipulate samples in our favor.