IJMO 2026 Vol.16(1): 1-5
DOI: 10.7763/IJMO.2026.V16.875
Digital Twin-Based Control and Monitoring of Industrial Robotic Arms Using Cloud CAD Platforms
Dragos-Alexandru Cazacu 1*,
Mihail Hanga 2, Carmen-Cristiana Cazacu 2, and Florina Chiscop 2
1. PTC Eastern Europe SRL, Romania and Robots and Production Systems Department, The Faculty of Industrial Engineering and Robotics, National University of Science and Technology Politehnica Bucharest, Splaiul Independenței 313, 060042 Bucharest, Romania
2. Robots and Production Systems Department, The Faculty of Industrial Engineering and Robotics, National University of Science and Technology Politehnica Bucharest, National University of Science and Technology Politehnica Bucharest, Romania
Email: acazacu@ptc.com (D.A.C.); mihail.hanga@stud.fiir.upb.ro (M.H.); carmen.cazacu@upb.ro (C.C.C.); florina.chiscop@upb.ro (F.C.)
*Corresponding author
Manuscript received November 5, 2025; accepted December 16, 2025; published January 14, 2026.
Abstract—This paper presents a low-cost, CAD-centric Digital Twin (DT) framework for joint-level control and monitoring of robotic arms using a cloud Computer Aided Design (CAD) platform. A Raspberry Pi 5 prototype (DRV8825 stepper driver and AS5600 magnetic encoder) is coupled to an Onshape assembly so that CAD mate values act as both command inputs and state variables. A lightweight Flask web interface provides local operation (slider/inputs, start–stop, emergency stop), while RESTful GET/POST requests synchronize the physical joint and the CAD model in near real time. To keep the motor loop responsive under cloud delays, encoder feedback is acquired on a dedicated 100 Hz thread and CAD updates are batched. Experiments report mean API round‑trip latencies of ~195 ms (GET) and ~205 ms (POST), an average cloud synchronization delay of ~200 ms, and a mean angular error of 0.33° ± 0.05° at 1/8 microstepping; local commands execute in ~0.8 s, while Onshape-mediated commands take 1.0–1.5 s depending on network load. Software interlocks, watchdog timeouts, and driver current limiting complement the mushroom-type E‑stop. A simple scalability analysis shows that sequential per-joint calls would accumulate latency (e.g., ~1.2 s for 6 joints), motivating batched updates for supervisory DT operation and future multi‑DOF validation
Keywords—Internet of Things (IoT), Raspberry Pi, digital twin, Computer Aided Design (CAD)
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Cite: Dragos-Alexandru Cazacu, Mihail Hanga, Carmen-Cristiana Cazacu, and Florina Chiscop, "Digital Twin-Based Control and Monitoring of Industrial Robotic Arms Using Cloud CAD Platforms," International Journal of Modeling and Optimization, vol. 16, no. 1, pp. 1-5, 2026.
Copyright © 2026 by the authors. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
