USF Robot - ROS 2 Joystick Control Demonstration

GitHub Repository: github.com/Nin...
This project, developed over the summer of 2024 for my university's Electrical Engineering department, features a 3D-printed robot designed and created by me for use in an Applied Robotics class. The robot's mechanical design was crafted using Autodesk Fusion, and it is programmed in Python on a Raspberry Pi 5 running Armbian OS (Ubuntu 22.04 LTS) and ROS 2 Humble Hawksbill.
** Update: Ramp logic is now implemented for link 1 and link 2 (buttons A, B, X and Y) **
Control System:
- Joystick: 8BitDo Ultimate C
- Mapped Controls:
Analog Stick (Axis 0, 1): Controls base rotation. Values from -32767 to 32767 are converted to degrees, then the angle difference is calculated to determine clockwise or counterclockwise movement.
Analog Stick (Axis 2, 3): Controls wrist rotation using the same conversion method as the base rotation.
Button LB: Closes the gripper. The position of the gripper is incremented by 480 units per press.
Button RB: Opens the gripper. The position of the gripper is decremented y 480 units per press.
Button A: Moves link 1 forward. The ramp logic gradually and quadratically increases the position of link 1.
Button B: Moves link 1 backward. The ramp logic gradually and quadratically decreases the position of link 1.
Button X: Moves link 2 forward. Gradually and quadratically increases the position of link 2 using ramp logic.
Button Y: Moves link 2 backward. Gradually and quadratically decreases the position of link 2 using ramp logic.
Mechanical Design:
- End Effector: Gripper secured with two racks and a pinion gear connected to the last servo (servo 4).
Wiring Schematics:
The Raspberry Pi 5 connects to a level shifter via TTL serial (Tx and Rx). The level shifter safely interfaces with the Raspberry Pi 5 with the Pololu Micro Maestro 6-channel servo controller by adjusting voltage levels. The system operates five servos (servo 0 to servo 4) powered by a 6V power supply.

[@ChrisLocke1969]

add ramping to servos, you'll be much more satisfied! Looking good, kudos!

[@Ninja_Ballerina]

Thank you for the suggestion! It moves more smoothly now with the gradual ramping. I updated my repository with the ramp logic in robot_controller.py. I appreciate the encouragement!

[@ChrisLocke1969]

@@Ninja_Ballerina you've done an amazingly great job - multiple axis robots are a challenge, you should be proud - can't wait to see what challenge you take on next! New subscriber, I am!

[@Ninja_Ballerina]

​@@ChrisLocke1969 Thank you so much for the kind words and for subscribing! Mapping the joystick inputs was indeed a fun challenge for a multiple-axis robot. I used jstest /dev/input/js0 to observe that the axes range from -32767 to 32767, which are 16-bit signed integer values. Seeing these ranges made me think of Cartesian coordinates, where the joystick's x and y positions can be interpreted as points on a 2D plane. I calculated the arctangent of the y and x values and converted them to degrees. After I determined the angle difference, I was able to map the joystick's motion to the robot's rotation direction. Believe it or not, the part I enjoyed the most was the mechanical design in Autodesk Fusion. I look forward to any more challenges and projects that I will partake in during my academic journey. Thanks again for the support!

[@ChrisLocke1969]

@@Ninja_Ballerina now THAT's how its done!! Impressive!

[@Nikalym]

gotta love engineering, gonna leave a sub right away!

[@ayishanecholi1353]

Farida Rocks!! Awesome🤩👏👏👏

[@Hajdew]

Cool Robot

[@sandulchandila]

That is awsome

[@savagesarethebest7251]

That is cool

[@user-om3ik2rl3o]

Smart ❤ and gorgeous ❤

[@Negmo]

HeHe