Gripper Bot: Ackermann Steering

Introduction:
I’ve begun working on an exciting new project: Gripper Bot, a robot designed to autonomously navigate its environment, avoid obstacles, build a map of its surroundings, and respond to voice commands. Its standout feature is a gripper assembly that allows it to pick up objects on command, imagine telling it, "Go grab my phone from the table," and watching it do exactly that.

Initial Design:
So far, I’ve completed the chassis, wheel assembly, and camera placement. I imported a DC motor and a Pi Camera module from GrabCAD, while designing and customizing the wheels in Fusion 360 to fit the motor mounts and chassis layout. This gave me a good foundation to virtually prototype the robot.

Ackermann Steering
The robot uses 4 wheels, but only the rear two are powered by DC motors, making this a 2-wheel differential drive system. However, I’ve taken inspiration from Ackermann steering to add a layer of realism to the front wheel design.

In traditional cars, when turning, the inner front wheel must rotate at a sharper angle than the outer one to follow their respective turning radii. This is what Ackermann steering handles through a steering linkage system. In my design, the front wheels are connected using a steering linkage based on Ackermann geometry, which allows them to rotate at different angles while turning — just like in real-world vehicles

Pictures:

What’s Next:
The next steps are crucial and exciting:

• Mounting the LiDAR and IMU: Strategically placing the sensors so that the robot gets accurate spatial awareness for SLAM and path planning.

• Designing the Gripper Mechanism: Creating a functional "hand" for the robot that can pick up and hold various household items.

• URDF Integration: Bringing the entire design into a Unified Robot Description Format (URDF) file for use in ROS, which is critical for simulation, motion planning, and control.

• Voice Command Integration: Using speech recognition tools to enable natural language commands, the goal is for the robot to understand and execute phrases like “Go to the kitchen” or “Bring me the book.”

Conclusion:
As I go forward, I’m documenting every step, successes and roadblocks alike, to learn how each subsystem contributes to building a truly autonomous assistant.