To achieve fluid "reach-and-grasp" capabilities in a simulated environment, I developed a comprehensive control framework that treated the Kuka YouBot’s omnidirectional platform and 5-DOF arm as a single, cohesive unit. By deriving and implementing custom Forward and Inverse Kinematics (FK/IK) from first principles, I enabled the robot to execute complex object-moving tasks with mathematical precision while respecting the physical constraints of real-world hardware.

Technical Challenges & Solutions

• The Redundancy Problem: With 8 total degrees of freedom (3 from the base, 5 from the arm), there are infinite ways to reach a coordinate. I engineered a solver that optimized for the "sweet spot" of the arm's reach, using the mobile base to position the robot so the arm always operated within its most dexterous workspace.

• Singularity Avoidance: Custom IK solvers often fail at extreme joint angles. I implemented numerical methods in Python to handle mathematical singularities, ensuring smooth, continuous motion during high-precision pick-and-place maneuvers.

• Sim-to-Real Fidelity: To ensure the simulation was a true Digital Twin, I integrated the exact mass, torque limits, and velocity constraints of the physical YouBot. This allowed the Python-based controller to govern the CoppeliaSim model as if it were the physical machine.

Technical Stack

• Control Logic: Python (NumPy for high-speed matrix calculations)

• Simulation Environment: CoppeliaSim (formerly V-REP)

• Communication: ZeroMQ / Remote API for real-time synchronization

• Mathematical Modeling: Denavit-Hartenberg (D-H) parameters and Holonomic Drive equations

Engineering Highlights

• Unified Motion Planning: Developed a "Whole-Body Control" approach where the base and arm move simultaneously, significantly reducing the time required to complete manipulation tasks.

• Custom Geometric Solvers: Built the FK/IK engine from scratch rather than using black-box libraries, allowing for granular control over individual joint priorities and obstacle avoidance.

• Holonomic Precision: Leveraged the 4-wheel omnidirectional drive to allow for translation and rotation in any direction, providing a level of maneuverability that standard differential-drive robots cannot achieve.