Types of Industrial Robots
Each robot architecture is optimized for a specific task envelope. Selecting the wrong type wastes budget and underperforms:
| Type | Axes | Payload | Best Applications | Key Trade-off |
|---|---|---|---|---|
| Articulated (6-axis) | 6 | 3–2,300 kg | Welding, painting, heavy handling | Most flexible but larger footprint & cost |
| SCARA | 4 | 1–20 kg | Assembly, insertion, pick-and-place | Very fast in XY plane; limited Z reach |
| Delta (parallel) | 3–4 | 0.5–8 kg | High-speed picking, food, pharma | Extremely fast cycle; small payload only |
| Cartesian (gantry) | 3 | Up to 100+ kg | CNC loading, dispensing, large-area | Simple & precise but rigid and slower |
| Collaborative (cobot) | 6–7 | 3–25 kg | Machine tending, inspection, assembly | Safe near humans; slower & lower payload |
Cobots vs. Traditional Robots
Cobots can operate alongside humans without full safety fencing — but they are not a universal replacement:
| Factor | Cobot | Traditional Robot |
|---|---|---|
| Safety standard | ISO/TS 15066 (force & pressure limits) | ISO 10218 (fenced cell, light curtains) |
| Max speed | <1.5 m/s (safety-limited) | Up to 10+ m/s |
| Payload | 3–25 kg typical | Up to 2,300 kg |
| Setup cost | $25K–$80K (arm + gripper) | $80K–$400K+ (arm + cell + guarding) |
| Best fit | High-mix / low-volume, flexible | High-volume, dedicated cells |
Cobot Misconception: "No Risk Assessment Needed"
Cobots still require a thorough risk assessment per ISO/TS 15066. A cobot holding a sharp tool or hot part can still injure an operator. Assess the end-effector, the part, and the environment — not just the robot arm.
Common Robot Applications
PLC Basics — The Brain of Automation
A Programmable Logic Controller (PLC) controls sequences, monitors I/O, and coordinates equipment in every automation cell:
- Inputs — signals from sensors, switches, encoders ("part present," "door closed")
- Outputs — commands to actuators, motors, valves ("extend cylinder," "start conveyor")
- Ladder logic — the most common PLC language; each "rung" maps a condition → action relationship
- Scan cycle — reads inputs, executes logic, writes outputs in a continuous 5–20 ms loop
- I/O modules — digital (on/off), analog (4–20 mA), and specialty (thermocouple, encoder) cards
Robot Programming Approaches
| Method | How It Works | Skill Level | Best For |
|---|---|---|---|
| Teach pendant | Jog robot to positions, record waypoints | Moderate — vendor syntax | Dedicated high-volume cells |
| Hand guiding | Physically move cobot arm through the path | Low — hours to learn | Simple cobot tasks, quick redeployment |
| Offline programming | 3D simulation (RoboDK, DELMIA) | High — CAD + kinematics | Complex paths, pre-validation |
| No-code platforms | Drag-and-drop flowcharts | Low — process knowledge | Frequent changeovers, high-mix |
Programming Tip
Always define a home position the robot returns to after every cycle and after any fault. Name every waypoint clearly — "P1" means nothing six months later.
Automation ROI — Calculating Payback Honestly
Projects that ignore integration and ongoing costs routinely miss payback targets:
✅ Include in Your ROI
- Labor savings (fully burdened rate × shifts eliminated)
- Quality improvement (scrap reduction, fewer reworks)
- Throughput gain (faster cycle, higher uptime)
- Safety benefits (reduced injury costs, lower insurance)
- Flexibility value (faster changeovers, new capability)
❌ Hidden Costs Often Missed
- Integration engineering (30–60% of arm cost)
- End-of-arm tooling (grippers, fixtures, sensors)
- Safety systems (guarding, scanners, light curtains)
- Programming, commissioning, & debug time
- Maintenance & spares (3–5% of system cost/year)
- Operator & maintenance training
Risk Assessment for Robot Cells
Every installation requires a formal risk assessment per ANSI/RIA 15.06 or ISO 10218 + ISO/TS 15066:
When NOT to Automate
Automate When
The task is repetitive, high-volume, hazardous, or quality-critical — and the process is stable with standard work in place. Automating a broken process just produces bad parts faster.
Do NOT Automate When
Designs change frequently. Volumes are too low. The task requires human judgment technology cannot replicate. Or — most critically — when you have not standardized the work first. Apply lean principles to stabilize, then automate.
Building an Automation Roadmap
A plant-wide strategy prevents random "islands of automation" that cannot communicate:
🎯 Key Takeaway
Successful automation is not about buying robots — it is about solving specific production problems with the right level of technology. Start with a clear problem, select the simplest robot type that addresses it, include ALL costs in your ROI, and never skip the risk assessment. The best roadmap begins with standard work and lean foundations, then layers in automation where it delivers proven, measurable value.
Interactive Demo
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