By the EVST Applications Engineering Team · Last updated 1 June 2026 · Reviewed by EVST robotics integration engineering
Choose a collaborative robot (cobot) when payloads stay under about 20 kg, layouts change often, and the robot must share space with workers; choose an industrial six-axis robot when you need heavy payloads, high sustained throughput, or harsh-environment duty. The decision is set by three factors — payload, environment, and flexibility — not by brand or price. This guide gives the selection rules, a side-by-side table, the safety standards that apply to each, and where most plants end up using both.
Key takeaways
- Payload / speed: cobots ≤ ~20 kg light work; industrial arms span ~3–800 kg, heavy and high-takt.
- Environment / people: a cobot can run fenceless after an ISO/TS 15066 risk assessment; an industrial arm runs guarded to ISO 10218 behind a fence or light curtain.
- Flexibility / changeover: cobots switch products in minutes via drag-teach; industrial arms excel at fixed-takt high volume.
- One-line rule: light + frequent changeover + beside people → cobot; heavy + high takt + harsh → industrial.
- Most real lines combine both — match each station to the right class.
This article is for engineers and decision-makers selecting robots for a new line or cell. It compares collaborative and industrial six-axis robots; it does not cover SCARA, delta or gantry/truss systems, or AMR transport.
The wrong way and the right way to choose
The wrong way is to start from price or brand. The right way is to look at the job. EVST scopes selection with what our engineers call the Job-First method: define each station’s payload, human interaction, takt and changeover frequency first, then match it to the class of robot — because the same plant often needs different classes at different stations.
Factor 1 — Payload and speed
A collaborative robot is built for light work, typically up to around 20 kg, at moderate speed, right alongside people. An industrial six-axis robot spans the full ~3–800 kg range at high, sustained speed — heavy handling, palletizing, structural welding and high-volume lines are its home turf. If the part is heavy or the takt is tight, the cobot’s force- and speed-limits will cap you; if the work is light and the value is in flexibility, an industrial arm is overkill and needs guarding the cobot avoids.
Factor 2 — Environment and people
This is where the safety standards diverge, and it matters more than payload for layout:
- A cobot has force control and collision detection. After an ISO/TS 15066 risk assessment sets force and pressure limits for the specific task, it can run fenceless, sharing a bench with operators — saving the floor space a safety cage needs.
- An industrial six-axis robot is fast and powerful. It runs guarded to ISO 10218 behind a fence or light curtain; you don’t put a hand in its envelope while it moves.
The key nuance: “fenceless” is a property of the task, not the robot. The same cobot is only fenceless within the limits the assessment sets — change the tool, part or speed and the assessment is redone.
Factor 3 — Flexibility and changeover
A cobot is drag-to-teach: hand-guide it through a path and the program is generated, so it switches products in minutes — ideal for many variants, small batches and frequent line changes. An industrial arm excels at fixed-takt high volume, where unit cost is amortized by output and changeover is less frequent. If you change products daily, the cobot’s minutes-not-hours changeover is decisive; if you run one high-volume part, the industrial arm’s speed wins.
Side-by-side comparison
| Factor | Collaborative robot (cobot) | Industrial six-axis robot |
|---|---|---|
| Typical payload | ≤ ~20 kg | ~3–800 kg |
| Speed / takt | Moderate | High, sustained |
| People interaction | Shares space (fenceless, ISO/TS 15066) | Guarded, ISO 10218 |
| Safety hardware | Force/collision limits | Fence or light curtain |
| Changeover | Minutes (drag-teach) | Slower; fixed-takt strength |
| Footprint | Compact, movable | Larger guarded cell |
| Best fit | Light, high-mix, beside people | Heavy, high-volume, harsh |
| Fastest payback driver | Flexibility, fast setup | Throughput, heavy duty |
The one-line decision rule
- Light payload + frequent changeover + work beside people → cobot.
- Heavy load + high takt + harsh or guarded environment → industrial six-axis.
- Look at the job first, the machine second.
It’s usually not either-or
In practice many lines combine both: cobots hold the precise, flexible, human-adjacent stations (fastening, light assembly, inspection), while industrial arms carry the heavy main line (palletizing, structural welding, die-casting tending). Selecting isn’t choosing a brand — it’s matching each station to the right class by process, payload, takt, human interaction and changeover frequency. A plant that forces every station onto one class usually overpays on the light stations or under-serves the heavy ones.
Where this plays out across industries
- Automotive powertrain — cobots for traceable bolt fastening and light assembly; industrial arms for heavy handling and structural welding.
- 3C and appliances — cobots for high-mix small-batch assembly and changeover-heavy lines.
- Metalworking and building materials — industrial arms for machine tending, heavy palletizing and die-casting.
Looking ahead, the line between the classes is blurring as higher-payload cobots and easier-to-program industrial arms appear, but the three-factor logic holds: pick by payload, environment and flexibility, not by the label on the arm.
FAQ
Is a cobot just a small industrial robot? No — the defining difference is collaborative operation: force/speed limits and a task-level ISO/TS 15066 assessment let it run fenceless beside people, which an industrial arm cannot.
Can a cobot really run without a fence? Only within the limits an ISO/TS 15066 risk assessment sets for that specific task; change the tool, part or speed and the assessment must be redone.
Which is cheaper? Neither universally — a cobot wins on light, high-changeover work by saving guarding and setup time; an industrial arm wins on heavy, high-volume work by throughput. Total cost depends on the job.
What payload is the cutoff? Roughly 20 kg is the practical line for cobots today; above that, or at tight takt, an industrial six-axis is usually the better fit.
Can I use both on one line? Yes, and most mature lines do — cobots at the flexible, human-adjacent stations and industrial arms on the heavy main line.
Making the call
Cobot or industrial robot — the answer is in your process, set by payload, environment and flexibility. EVST selects by station with the Job-First method and integrates whichever class fits each step, rather than pushing one brand — see our application guides to robot machine tending, heavy palletizing and die-casting tending, or talk to EVST about a station-by-station selection for your line.
About the author — The EVST Applications Engineering Team designs and integrates both collaborative and industrial robot cells for manufacturers across automotive, electronics, appliance and metalworking industries. The team selects by station — payload, human interaction, takt and changeover — using the Job-First method described above, rather than standardizing on a single class or brand. Reviewed by EVST robotics integration engineering for technical accuracy; payload and takt figures are typical ranges, not guarantees, and are confirmed per project. Corrections and updates: see the Last Updated date.