Robot selection should be the result of a task and cell study. Payload is important, but cycle, reach, tooling, people, safety, presentation and lifecycle determine whether the system works.
Begin with the application, not the label
“Robot” and “cobot” are useful shorthand, but they do not define the final cell. A collaborative robot may still require guarding or other protective measures, while a conventional industrial robot may be the more appropriate platform for a fully enclosed high-rate task.
Describe what the system must do, how people interact with it and what happens during normal production, replenishment, cleaning, setting, recovery and maintenance. Platform selection follows from that operating model.
Cycle and utilisation
Start with the complete cycle: approach, grip, process, travel, release, confirmation and return. Include product presentation, machine dwell, vision, tool changes and fault recovery. A headline robot speed does not reveal the sustainable cell output.
Where the required cycle is close to the theoretical limit, model realistic acceleration, payload, path, settling and upstream variability. Add a sensible operating margin rather than designing around a perfect demonstration.
Payload, reach and inertia
Payload includes the tool, product, adapters, services and any change mechanism. Reach must cover the real path while maintaining suitable joint positions and clearance. Large or offset loads can be limited by inertia and moment before nominal payload is reached.
A good concept plots the complete envelope and checks the difficult poses: low pick points, deep machine access, rotated tools and service routing.
Human interaction and safety
Decide why people need to be near the task. Is proximity essential to the process, useful only for replenishment, or simply inherited from the current manual method? The answer affects layout, safeguarding and economics.
Collaborative operation is an application-level decision that requires assessment of the robot, tool, workpiece, speed, contact possibilities and operating modes. A product marketed as collaborative does not remove the need for competent risk assessment and validation.
Tooling and part presentation
End-of-arm tooling can dominate reliability. Surface finish, porosity, flexibility, tolerance, contamination and orientation all affect the grip method. The feeding or fixture concept must present the part within the window the tool can tolerate.
Trial representative parts early when the grip is uncertain. A robot cannot compensate indefinitely for inconsistent presentation or an unstable pack.
Whole-life economics
Compare the complete cell: robot, controller, tooling, base, guarding, sensors, conveyors, integration, programming, training, maintenance and changeover. Include the cost of lost output if the concept has insufficient cycle margin or is difficult to recover.
The right platform is the one that meets the production objective with an acceptable risk, operating model and lifecycle—not the one with the most attractive standalone specification.
- Define the complete task and operating modes first.
- Model sustainable cell cycle, not headline robot speed.
- Include tooling and product in payload and reach decisions.
- Treat collaboration as an application assessment, not a product label.
- Compare whole-cell economics and recovery, not robot price alone.