Overview
The CNC robot tending cell is a full end-to-end integration — mechanical frame, electrical panel, robot programming, PLC sequencing, safety architecture, and commissioning documentation. The cell uses a FANUC robot to load and unload a CNC machine, with a 7th-axis linear track for extended reach.
This was a significant project spanning all engineering disciplines simultaneously. The mechanical frame was designed and fabricated in-house, the electrical panel built from scratch, and the PLC/robot programs developed in parallel with the hardware.
The brief
Automate the tending of a CNC machine using a FANUC robot. The robot needed to collect raw parts, load the CNC, wait for cycle completion, unload the finished part, and place it at a handover point — all within a guarded cell with full safety interlocking.
Key decisions
The 7th-axis linear track was added to give enough reach without requiring a larger (heavier, more expensive) robot. The safety architecture uses dual-channel STO with door monitoring via a Pilz safety relay — tested and verified to PLd.
PLC sequencing handles all handshakes between the robot and CNC — door open/close requests, part-in-position confirmations, and fault/recovery states. The robot program uses a Karel-based recipe system so different part families can be selected from the HMI without reprogramming.
"The constraint that forced the best decision was the floor space limit — working around it gave us a better layout than the original plan."
What was delivered
- ✓Fabricated 7th-axis linear track and cell frame
- ✓Full electrical panel with safety relay and STO wiring
- ✓FANUC TP programs with recipe system
- ✓Siemens TIA Portal PLC program with full alarm set
- ✓WinCC HMI with status display and recipe selection
- ✓Commissioning report and acceptance test records
Project milestones
Floor plan, reach study in Roboguide, equipment selection
7th-axis track, cell frame, EOAT design and build
Scheme, panel build, safety circuit wiring, IO schedule
Sequence logic, alarm structure, recipe system, HMI
Trace-based bring-up, acceptance tests, punch list resolution
Documentation pack, training session, operator guide
Gallery
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