Apkudo Robotics Systems Engineer interview questions

1. Factory Automation Systems PLC/SCADA: How does a PLC differ from a DCS in a large-scale factory, and when would you choose one over the other? Describe how you’d architect a SCADA system to monitor and control 500+ I/O points across multiple production lines. Fieldbuses & Networks: Compare PROFIBUS, EtherNet/IP, and PROFINET in terms of topology, determinism, and bandwidth. How do you troubleshoot intermittent data loss on a Ring Ethernet topology? Sensors & Actuators: Explain how you’d select and calibrate different types of proximity sensors for a high-speed pick-and-place robot. A pneumatic cylinder is drifting—what diagnostic steps and measurements do you take? Safety & Standards: What are the key safety functions defined by IEC 61508/SIL, and how would you implement a SIL 2 emergency stop? How do you integrate functional safety into a conveyor-belt interlock? 2. Mechatronics Fundamentals Control Systems: Derive the transfer function of a DC-motor driven axis with gearbox and load inertia; how do you design a PID for it? Explain how sensor noise affects closed-loop performance and methods to mitigate it. Mechanical Design: How do you perform a modal analysis on a robotic arm link to avoid resonance at 5 Hz? Describe how you’d choose materials and cross sections to minimize deflection under a 50 N load. Electronics & Embedded: What considerations go into designing a PCB for an H-bridge motor driver (EMC, thermal, current)? How would you implement current sensing and protection to prevent stall damage? Integration Challenges: Walk me through integrating a new servo drive into an existing motion-control network. What’s your process for verifying alignment between mechanical encoder feedback and actual shaft angle?