Cody

Cody is a robot for the next season of WRO Robomission Senior.

The World Robot Olympiad (WRO) is a global robotics competition. For the Robomission challenge, you have to design, build and program a robot to complete a set of challenges on a board in under 2 minutes. Cody is our attempt at making our best robot so far, and I'm designing it to be faster, more precise and more reliable than all of our previous.

This year's challenges

1. There is a mosaic with a randomized pattern of colors at the center of the board. You have to place a block of the right color in each square of the grid to score.

2. There are blocks of "cement" of different colors on the board. You have to carry the blocks of each color to their corresponding area.

Our solution

1. A toolhead grabs and drops blocks for the mosaic by using wheels

2. A mill picks up, carries and releases two colors of cement at a time

How it works

• Electronics: I'm using an ESP32 as the microcontroller, an MPU9250 IMU for orientation and a TCS34725 color sensor for detecting the lines on the board. I'm also using an ADS1115 ADC for measuring the voltage of the battery and a PCF8575 GPIO expander.
• Camera: I'm using an ESP32-CAM to detect the color pattern of the mosaic.
• Actuators: I'm using JGB37-3530 motors for the wheels and N20 motors for the toolhead and for the mill. I'm using TB6612FNG drivers to control them.
• Power: I'm using a 3S 2200mAh LiPo battery for powering the robot. I'm also using a voltage regulator for powering the ESP32.
• Structure: I'm using 3D printed structural parts that have attachments for the components. I will be printing them out of PETG. I'm also using standard hardware such as bearings, carbon fiber rods and castor wheels.
• Software: I'm using odometry and a Pure Pursuit algorithm for control.

Why I made this

My team has been using Lego Spike since we started competing, but it's starting to show its limitations. Last year, we went to the international final for the first time. Robomission had opened up to all hardwares for the first time this year, which means other teams could make faster, more precise and more reliable robots than what we could possibly do with Lego. I'm designing this robot to be faster, more precise and more reliable than our previous robots with the power of open hardware.

PCB

Wiring diagram

Onshape Document

https://cad.onshape.com/documents/a1e1109ed4daddff079aebb8/w/75daa850bdae83d3a805f11b/e/0ab81b698f3d6ebcf8c57589?renderMode=1&uiState=69baba64dff3c3ac052b00d2

Cart screenshots

Note: I will be buying two of the carbon fiber rods above but AliExpress didn't feel like allowing me to add more than one to my cart at the moment

BOM

Note that the amount to buy might be higher than the amount to be used because the item is sold in bulk

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Made with ❤️ for Blueprint thanks to Hack Club