Autonomous Pen Grasping

In this project, I developed a vision-guided robotic arm capable of detecting and retrieving a pen from a human hand. The system uses an Interbotix robotic arm controlled via a ROS 2 Python interface, integrating computer vision, kinematics, and motion planning to achieve precise grasping.


School: Northwestern University
Location: - Evanston, IL
Duration: September 2025


Github Link: https://github.com/ncknight-un/Interbotix_Pen_Grasping

Enclosure & CAD Designs:


Core Challenge

The primary challenge was coordinating perception with manipulation:

  • Detect the pen’s position and orientation in real time
  • Plan a feasible trajectory given the arm’s 5-DOF constraints
  • Execute a smooth and accurate grasp

System Implementation

  • Python scripts interface with ROS 2 nodes
  • Camera input is processed to extract target coordinates
  • Motion commands are generated and sent to the robotic arm
  • Kinematics and planning ensure feasible and precise movement to grasp pen

Skills Improved:

  • Perception: Vision-based object detection and pose estimation using an Intel RealSense camera
  • Python: Data processing, trajectory planning, and robotic control
  • System Integration: Combined perception and control into a unified pipeline
  • Calibration: Sensor and system calibration for accurate perception and motion

Key Takeaway:

This was my first hands-on experience with ROS 2 and robotic manipulation. It provided practical insight into how robots perceive their environment and execute controlled movements.

Working on this system strengthened my understanding of vision-based perception, motion planning, and precise control, allowing me to demonstrate how these components come together in the real-world for robotics applications.