Multi-Arm Coordination — 2-DOF QUANSER
Master-slave force/position control for coordinated dual-arm object manipulation.
Per Arm
Architecture
Research Lab
Tech Stack
The Problem
When two robot arms work together to move the same object, they can accidentally pull in opposite directions — bending, dropping, or damaging whatever they're holding. Getting them to truly cooperate requires one arm to constantly sense the forces the other is applying and adjust in real time, which is much harder than it sounds.
The Challenge
Coordinating two independent robotic arms to manipulate a shared object requires real-time synchronisation of force and position feedback. One arm acting purely on position commands would cause the object to slip or deform if the other arm exerted unexpected forces. The system needed a control architecture where one arm "felt" the interaction forces and the other precisely tracked the desired trajectory.
Architecture & System Design
Two robot arms coordinate to manipulate shared object: master arm controls trajectory, slave arm adjusts force/compliance based on real-time feedback. Hybrid control law balances position accuracy with force regulation.
The QUANSER 2-DOF arms were interfaced through QUARC real-time control software running MATLAB/Simulink models. The master arm was configured in position control mode, providing the desired trajectory. The slave arm ran an impedance controller that regulated the contact force, adjusting its compliance based on real-time force/torque feedback. A hybrid force-position control law was derived analytically and validated in simulation before hardware deployment.
Code Walkthrough
3-step walk-through of the production implementation — file paths and intent shown above each block.
Results
The master-slave system successfully demonstrated coordinated object manipulation with stable force regulation. The impedance controller maintained contact forces within ±0.2 N of the setpoint during dynamic manipulation tasks, enabling safe and compliant interaction with the shared object.
Gallery & Demos
QUANSER Dual-Arm Hardware
Two 2-DOF robot arms configured in master-slave arrangement for coordinated object manipulation.
Experimental Setup
Laboratory test configuration with shared object, force/torque sensors, and real-time control interface.
Force Tracking Performance
Time-series plot showing impedance controller regulation of contact forces during object manipulation.
Simulink Control Model
Real-time block diagram of the hybrid force-position control law running on QUARC.
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Interested in this work?
Full architecture walkthrough and code review available during interviews.