Three-shift bar-lathe cell
A robot cell that keeps a bar lathe running three shifts, while the machine stays fully usable by hand.
2018–20 · GreenBau, Romania · Industrial robotics
The problem
A maker of rods and tubes for pneumatic and hydraulic cylinders could not hire enough skilled operators to staff all three shifts. They already owned the lathe. They needed a cell that feeds it three part types in series production on its own, without losing the option to walk up and run the machine manually.
Requirements
- Three cylindrical part types, Ø30–50 mm, 500–650 mm long
- Work with the wooden crates the plant already uses
- As few moving parts as possible
- An open cell, no full fence
- Manual work at the machine without the robot in the way
- Full integration with the lathe
- A simple HMI for the operator
What was built
- A double gravity conveyor that holds a 4–5 hour buffer, so the cell runs through a shift unattended
- Half the cell fenced, the other half open and guarded by a safety lidar, with several zones where the robot slows down or stops when a person walks in
- The robot mounted on an inclined base, which keeps the machine front free for manual work
- Full machine interface through a dedicated connection, plus pneumatic actuators that open and close the lathe doors
- An inclined station for the crates the plant already works with, and a workbench for manual mode
- Pneumatic magnetic grippers that pick the whole range of diameters
- An HMI built inside the robot’s teach pendant to switch programs, set parameters and read status and faults
Challenges
- Pick every diameter without a tool change, fast
- A double magnetic gripper, pneumatically actuated, with routed cabling to keep the cycle short
- Let people and forklifts work around an open cell
- Safety lidar with layered zones instead of a full fence
- Hand loading must stay safe even with the robot present
- Robot current monitoring and force sensing while a worker feeds the machine
Technology
Kawasaki · Okuma · Safety lidar · Magnetic gripper · Pneumatics · HMI on teach pendant · Ethernet/IP
At a glance
- ROBOT
- Kawasaki
- MACHINE
- Okuma GENOS L3000E-M
- PARTS
- 3 types, Ø30–50 × 500–650 mm
- BUFFER
- 4–5 h gravity conveyor
- SAFETY
- half fence, half safety lidar
My role. Designed and commissioned the cell layout, gripper, safety, robot programs and PLC
Screens
