Where Are Safety Mats, Safety Edges, and Safety Bumpers Used?
Typical applications, design tips, and compliance notes for pressure-sensitive protective devices in modern automation cells.
1) Quick definitions (so we’re talking about the same things)
- Safety mats (pressure-sensitive mats): floor sensors that trip when a person steps on a defined area to command a safe stop before contact.
- Safety edges (pressure-sensitive edges): deformable rubber profiles mounted on a moving edge (gates, AGVs, machine tables) that trip on first contact.
- Safety bumpers: thicker, energy-absorbing versions of edges for higher inertia or larger stopping distances.
Standards context you’ll see in data sheets: ISO 13856 series (pressure-sensitive protective devices), ISO 13849 (control reliability/PL), ISO 13855 (positioning of safeguards), IEC 60204-1 (machine electrical).
2) Safety mat applications — presence before contact
- Robot cells & gantries: define stop/slow zones when optical devices struggle with glare/coolant.
- Press brakes & forming: foot area detection near danger zones; integrates with SS1/SS2.
- Packaging & palletizing: perimeter entry points where gates must stay open for flow.
- Assembly/test cells: quick to deploy and re-layout during line changeovers.
- Stage machinery (industrial class): keep -out zones near lifts and moving platforms under low light or smoke.
3) Safety edge applications — contact on a moving edge
- Automatic doors & shutters:bottom/vertical edges halt motion on contact.
- Machine tables & moving guards:prevent crushing between moving/fixed parts.
- Conveyors & shuttles: front lip and side edges on pushers and transfer carts.
- AGVs/AMRs: perimeter edges provide last-ditch contact stop complementing lidar/cameras.
- Theater scenery (industrial builds):edges on moving set pieces for crew protection.
4) Safety bumper applications — high-energy zones
- Large AGVs & transfer carts: thick bumpers add energy absorption and safe stop.
- Heavy carriages & gantries: bumpers at ends/undersides where slow but massive impacts can occur.
- Automotive body shops: rotating fixtures and tight entrances that need longer pre-travel.
- AS/RS systems: maintenance-aisle bumpers on shuttles and lifts.
5) Choosing between mat, edge, or bumper
| Question | Choose… | Why |
|---|---|---|
| Need presence detection before reaching the hazard? | Mat | Detects a person stepping in; contact not required. |
| Clearly defined moving edge may strike/pinch? | Edge | Stops motion at first contact along that edge. |
| High mass or non-negligible speed? | Bumper | Energy absorption and larger pre-travel. |
| Optical sensors fail (steam, chips, glare)? | Mat | Unaffected by light and airborne reflections. |
| Space extremely tight? | Edge | Low-profile device on the moving member. |
Many cells combine devices: e.g., lidar for warning + edge/bumper for contact stop; gate switch + mat at the operator station.
6) Integration & performance (what engineers check)
Safety control architecture
- Use a certified safety relay/PLC to meet required PLr (ISO 13849-1).
- Dual-channel devices with EDM are typical for PL d/e.
Stopping distance & placement
- For mats: position so a person cannot reach the hazard before safe state is achieved.
- For edges/ bumpers: pre-travel + controller response + drive stop ≤ available clearance (ISO 13855).
Environment & diagnostics
- Check IP rating, chemical resistance, temperature range; protect cables with sealed glands.
- Prefer short/open-circuit monitoring; add HMI alarms/beacons for downtime reduction.
Reaction time budget
- Sensor response + cabling/relay + drive stop; consider worst-case AGV speed/gradient.
7) Examples that work well in practice
- Press brake: front mat + rear light curtain into a safety PLC for SS1.
- AGV: lidar for slowdown + front bumper for the last 50–100 mm contact stop.
- Roll-up door: bottom edge stops/reverses on contact; side photoeyes add pre-contact detection.
- Robot cell: dual mats (operator panel & feeder zone) with local teach zoning.
8) Installation & maintenance checklist
- Mats: use beveled ramps; remove trip hazards; seal cable entries; proof-test each shift.
- Edges/ bumpers: mount rigidly for proper compression; verify actuation along the full length, including corners.
- Control system: validate safe stop category (STOP/SS1/SS2) and restart interlock; enable EDM.
- Records: keep PL calculations, layouts, and periodic test logs in the technical file.
9) FAQs
Can I use mats where pallets roll through?
Yes—use modular layouts with robust ramps and protected cable channels. Keep caster impact angles shallow to avoid premature wear.
Do edges replace laser scanners on AGVs?
No. Edges/bumpers provide contact stop; scanners/cameras provide pre-contact detection and speed control. Use both.
How long do mats last?
Quality mats are rated for millions of operations. Life depends on traffic, chemicals, and mechanical abuse—plan inspection and replacement intervals.