How to Choose an Industrial Robot Arm: The 2026 Buyer's Guide

Most plants buy the wrong arm because they shop from the payload column of a catalog. A production engineer needs to move a 6 kg part into a CNC, reads that one robot lifts 7 kg and another lifts 12 kg, picks the bigger number for headroom, and discovers on the floor that the reach was 200 mm short of the chuck, the cycle time missed the takt by a second and a half, and the wrist could not tilt the part into the fixture without a collision. The payload number was the least of the constraints that actually mattered, and it was the only one they checked.

The order that works starts from the cell, not the robot. Define the task first: what the arm picks, from where, to where, how fast the line demands it, what the part weighs at full reach with the gripper attached, and what the environment does to the machine (coolant, weld spatter, wash-down, dust, heat). That single description fixes the architecture, then the reach envelope, then the payload including end-of-arm tooling, then the repeatability your process can tolerate, and only then does a specific model number fall out. An industrial robot arm is a reach envelope with a payload rating at the wrist, a repeatability spec, an environmental seal, and a controller with a fieldbus, and you are buying all five at once, wrapped in an integration project that usually costs more than the robot.

This guide is the buying hub for industrial arms on this site. It gives you a decision framework by architecture (6-axis articulated, SCARA, delta, cartesian), the specs that actually decide a cell and how to trade them, the payload-at-reach math that catches most buyers, cost bands with what each one buys, the vendor landscape by category, the cobot-versus-industrial-arm question, and the integration and total-cost-of-ownership math that decides whether the project pays back. Throughout it points at the deeper industrial robot arms guide and at the live industrial arm leaderboard, where you can sort real robots by payload, reach, repeatability, and axes instead of trusting a datasheet.

The take: Choose the task before the arm. The motion and the environment pick the architecture (6-axis for dexterity, SCARA for fast planar pick-and-place, delta for high-speed light sorting, cartesian for long straight strokes), the geometry of the part flow sets the reach envelope, the part weight plus the gripper sets the payload you must rate at full extension, and the process tolerance sets the repeatability. Get those four right and the shortlist is three or four models across two vendors. The two questions that eliminate the most robots fastest are "what is my payload at maximum reach, including the tooling" and "what does my environment demand of the seal and the mounting." Answer those first and the datasheet stops lying to you.

Companion reading: industrial robot arms, how to choose a cobot, machine vision, robot safety & functional safety, end effectors & grippers, and motion planning & kinematics.

Table of contents

1. Key takeaways
2. Start with the task, then pick the architecture
3. The specs that decide a cell
4. Payload at reach: the math that catches buyers
5. Repeatability, speed, and the takt-time trade
6. Environment, protection, and mounting
7. Controller, I/O, and the fieldbus question
8. Cobot vs industrial arm
9. Cost bands and what each buys
10. Integration and total cost of ownership
11. The vendor and ecosystem landscape
12. A repeatable selection process
13. Frequently asked questions
14. Changelog

Start with the task, then pick the architecture

Four architectures cover almost every industrial arm purchase, and each wins a different class of task. Find your motion here, then let it tell you which specs to weight and which sibling guide to read next.

Architecture	Motion it is built for	Typical payload	Typical reach	Repeatability	Where it wins
6-axis articulated	Arbitrary position and orientation	3 to 300+ kg	0.5 to 3.5 m	plus or minus 0.03 to 0.1 mm	Welding, material handling, machine tending, assembly with orientation
SCARA	Fast planar pick-place, vertical insertion	1 to 20 kg	0.1 to 1 m	plus or minus 0.01 to 0.03 mm	Electronics assembly, dispensing, high-speed pick-place
Delta / parallel	Very fast, light, top-down picking	0.1 to 8 kg	0.3 to 1.6 m diameter	plus or minus 0.02 to 0.1 mm	Food/pharma packaging, sorting, high-rate line picking
Cartesian / gantry	Long straight strokes, large area	5 to 1000+ kg	meters, custom	plus or minus 0.05 to 0.5 mm	Palletizing, large-part handling, machine loading over distance

A sentence each on what actually decides the fit, because the headline spec is often a distraction.

6-axis articulated. The general-purpose workhorse. Six rotary joints give the wrist full position and orientation freedom, so it can approach a part from any angle, tilt it into a fixture, follow a weld seam, or reach around an obstacle. You pay for that dexterity in complexity, footprint, and cost per unit of speed. Choose it when the task needs orientation control or reach into awkward geometry: arc and spot welding, machine tending, complex assembly, painting, and general material handling. This is the category most of this guide is about, and the deep treatment is in the industrial robot arms guide.

SCARA. Selective Compliance Assembly Robot Arm. Rigid in the vertical axis and compliant in the horizontal plane, it is built for fast pick-place and top-down insertion where the part moves in a plane and drops straight down. It beats a 6-axis arm on cycle time and cost for that motion and holds the tightest repeatability in the field, down to plus or minus 0.01 to 0.02 mm. Choose it for electronics assembly, dispensing, screwdriving, and planar pick-place at high rate. It cannot tilt or reorient a part, so the moment your task needs orientation you are back to 6-axis.

Delta / parallel. Three or four arms driven from a fixed base above the work, moving a light platform at extreme speed and acceleration. It picks hundreds of light items per minute off a moving belt. Choose it for food and pharmaceutical packaging, sorting, and high-rate line picking of small light parts. Payload is low (often under 3 kg) and it works top-down over a defined volume, so it is a specialist, not a general handler.

Cartesian / gantry. Linear axes in X, Y, and Z, often overhead, giving a large rectangular work volume and long straight strokes with high stiffness. It scales to very large parts and very heavy loads that would need an enormous articulated arm. Choose it for palletizing, large-part or long-part handling, and loading machines spread across distance. It trades dexterity for reach and stiffness, and it usually needs more floor or overhead structure. The linear-motion building blocks are covered in linear motion systems.

Rule of thumb: If you cannot describe the motion in one sentence with a rate attached, you are not ready to pick an architecture. "Pick a 2 kg part off a moving belt at 90 per minute and place it in a tray" points straight at a delta. "Tend two CNCs, load a 6 kg blank and unload a finished part with a flip" points at a 6-axis. "Move a 4 kg part in a plane and press it down at 120 cycles a minute" points at a SCARA.

The specs that decide a cell

Once the architecture is fixed, a handful of numbers do the real work. Here is what each one means and, more usefully, what it trades against.

Payload. The mass the arm can carry at the wrist, but the rating is a best case at a defined center of gravity and inertia. Your real payload is the part plus the gripper plus any hoses, cameras, or sensors on the wrist, evaluated at your actual reach and orientation. See the next section, because this is where most buyers go wrong.

Reach. The maximum horizontal distance from the base axis to the wrist. The useful number is the work envelope shape, not the single reach figure, because a 6-axis arm cannot reach its maximum radius at every height or orientation. Overlay your part flow (infeed, machine, outfeed, fixtures) on the manufacturer's envelope diagram before you trust a reach number. Buying too much reach costs payload, speed, and cost; buying too little strands a fixture out of range.

Number of axes. Six is standard for general articulated arms and gives full orientation. Four-axis arms (many SCARAs and palletizers) are faster and cheaper for planar or top-down tasks that do not need tilt. Seven-axis arms add a redundant joint for reaching around obstacles and into confined spaces, at added cost and control complexity. Buy the axes the motion needs; extra axes are speed and money you carry for a day that may never come.

Cycle speed. The number that decides whether you hit takt. Manufacturers quote standard cycle times (a defined pick-move-place path, often the 25/300/25 mm "adept cycle") and maximum joint speeds, both best-case with a light load. Real cycle time depends on your path, your payload, and the acceleration limits with your inertia, so derate quoted figures and, for a tight takt, ask the vendor or integrator to simulate your actual path. Speed and payload trade against each other through inertia.

Repeatability. How closely the arm returns to a taught point, run to run, typically plus or minus 0.02 to 0.1 mm for industrial arms. Distinct from accuracy (how close it gets to a commanded coordinate it was never taught), which is looser and matters for offline programming and vision-guided work. Buy the repeatability your process tolerance needs; see the dedicated section below.

Mass and footprint. A heavier arm needs a stiffer mount and eats floor. Some tasks want a compact, wall- or ceiling-mounted arm to keep the floor clear; confirm the robot is rated for your mounting orientation, because not all are.

Here is how the common trades line up:

You want more	You give up	When it is worth it
Reach	Payload, speed, stiffness, cost	Large parts, spread-out fixtures
Payload	Speed, cost, footprint	Heavy parts, multi-part grippers, palletizing
Cycle speed	Payload headroom, sometimes accuracy	High-rate lines, tight takt
Repeatability	Cost, sometimes speed	Precision assembly, tight fits
Axes (7 vs 6)	Cost, control simplicity	Reaching around obstacles, confined cells
Environmental sealing	Cost, sometimes payload	Coolant, wash-down, foundry, cleanroom

War story: A shop bought a 20 kg-rated arm to tend a lathe with a 9 kg part, confident the 11 kg of headroom covered the gripper. The two-jaw gripper with its cylinder and mount weighed 6.5 kg, the part sat 250 mm off the flange, and at the machine door, near full reach, the effective rating dropped to 13 kg. The 9 plus 6.5 equals 15.5 kg load exceeded it, the arm faulted on inertia limits at speed, and they had to slow the cycle 30% to run it at all, blowing the takt. The next size up would have run the cell as designed. Rate the load at reach, with tooling, then add margin.

Payload at reach: the math that catches buyers

The single most common industrial-arm buying mistake is treating payload as a flat number. It is a curve that falls off with distance and with the inertia of the load, and the wrist rating on the front of the datasheet is the peak of that curve at an ideal center of gravity.

Three things reduce the payload you can actually use:

Reach. A 6-axis arm's usable payload drops toward the edge of its envelope. A robot rated 12 kg at the wrist may deliver 8 to 10 kg at full horizontal extension. Read the payload diagram (the load-versus-distance chart in the datasheet) rather than the headline number.

Center of gravity offset. The rating assumes the load's center of gravity sits within a small distance of the wrist flange. A gripper that holds the part 200 to 300 mm out from the flange creates a moment the wrist motors have to hold, and it eats into the rating fast. Long or offset tooling can halve the usable payload.

Inertia and speed. Moving mass fast means accelerating and decelerating inertia, and every arm has moment-of-inertia limits at the wrist joints. Run the robot fast with a high-inertia load and it will fault or force you to slow down, giving back the cycle time you bought the robot for.

The practical procedure: add the part mass and the full end-of-arm tooling mass (gripper, cylinder, mount, sensors, cables), locate the combined center of gravity relative to the flange, evaluate it against the payload-at-reach diagram at your worst-case reach and orientation, and then leave 20 to 30% margin. Most serious vendors offer a payload-check or load-verification tool (FANUC, ABB, KUKA, Yaskawa all publish one); run your numbers through it before you commit. The gripper choices that drive this are covered in end effectors and grippers.

Rule of thumb: The number that matters is (part mass + tooling mass) at (your reach, your orientation, your speed), with 20 to 30% margin left over. If that lands you between two size classes, size up. Undersizing payload is the mistake you pay for every cycle for the life of the cell.

Repeatability, speed, and the takt-time trade

Repeatability and speed are the two specs buyers most often over- and under-buy, because the datasheet numbers are seductive and rarely reflect the process need.

Repeatability by class. Precision SCARAs hit plus or minus 0.01 to 0.02 mm. General 6-axis arms sit around plus or minus 0.02 to 0.05 mm for smaller, precise models and plus or minus 0.05 to 0.1 mm for larger handling arms. Heavy palletizers and long-reach arms are looser, plus or minus 0.1 to 0.5 mm, and that is fine for their job. Match the spec to your tightest process tolerance with margin: if you are placing a connector into a socket with 0.1 mm clearance, you want repeatability well inside that; if you are palletizing boxes, plus or minus 0.5 mm is plenty and buying tighter is wasted money.

Repeatability differs from accuracy. Repeatability is return-to-taught-point consistency; absolute accuracy (hitting a coordinate you never taught) is looser, often ten times worse, and matters when you program offline from a CAD model or guide the robot with vision. If your workflow is offline programming or machine vision guidance, ask about absolute accuracy and calibration, and budget for a calibration routine, because the taught-point repeatability spec will not tell you what you need to know.

Speed and takt. Cycle time is what pays back the cell. Quoted cycle times assume a light load and a standard path; your part, your path, and your inertia will be slower. For a tight takt, do not trust the standard cycle figure. Have the vendor or integrator simulate your exact path with your payload in their offline software (RoboGuide, RobotStudio, KUKA.Sim, MotoSim), which is the same tooling used for simulation and digital twins. A simulation that shows 4.2 seconds against a 4.5 second takt with no margin is a warning, not a pass.

Process	Repeatability you need	Why
Palletizing, box handling	plus or minus 0.1 to 0.5 mm	Coarse placement, big tolerances
Machine tending	plus or minus 0.05 to 0.1 mm	Chuck/fixture entry, moderate fits
Arc welding	plus or minus 0.05 to 0.1 mm	Seam following, path consistency
General assembly	plus or minus 0.02 to 0.05 mm	Part mating, moderate clearances
Electronics / precision assembly	plus or minus 0.01 to 0.02 mm	Tight fits, small components

Rule of thumb: Buy repeatability tighter than your worst process tolerance with a safety margin, then stop. A plus or minus 0.02 mm robot on a palletizing job is money spent on a number nobody measures. A plus or minus 0.1 mm robot on a 0.05 mm assembly fit is scrap you will chase forever.

Environment, protection, and mounting

The environment is a hard filter that removes models before performance matters, and buying the wrong seal is a repair contract you signed by accident.

Ingress protection. The IP code rates sealing against solids (first digit) and liquids (second). Standard industrial arms are often IP54 on the body and IP65/67 on the wrist. Machine tending in coolant spray, or any wash-down cell, wants IP67 or a dedicated wash-down variant with sealed connectors and food-grade materials. Buying an IP54 arm for a coolant-drenched CNC cell means coolant in the wrist bearings and a service call, not an if but a when.

Specialized variants. Vendors offer purpose-built versions for hostile environments: foundry-grade arms with extra sealing and heat protection for die casting and forging, cleanroom-rated arms (ISO Class 3 to 5) for semiconductor and pharma with low particle generation, wash-down and food-grade arms with smooth surfaces and food-safe grease, and paint/explosion-proof (ATEX) arms for spray booths. These cost more and sometimes trade a little payload for the sealing, and they are non-negotiable where the environment demands them.

Mounting. Confirm the robot is rated for your mounting orientation. Floor mount is standard. Wall, ceiling (inverted), and angled mounts keep the floor clear or fit the cell geometry, but not every model supports every orientation, and inverted mounting can change the usable envelope and payload. If you plan to invert or wall-mount, verify it in the datasheet and in the payload tool, because a floor-only arm hung from a ceiling is a warranty problem waiting to happen.

Environment	What to specify	Why
Dry assembly / handling	Standard IP54/65	No liquid exposure
Machine tending in coolant	IP67 wrist, sealed body	Coolant intrusion kills bearings
Wash-down (food, pharma)	Wash-down/food-grade, IP69K	Caustic cleaning, hygiene
Foundry / forging	Foundry-grade, heat + seal	Heat, scale, spatter
Cleanroom (semi, pharma)	ISO Class 3 to 5 variant	Particle limits
Paint / solvent	ATEX / explosion-proof	Flammable atmosphere

Safety rule: Specify the environmental variant before you compare performance, and confirm the mounting orientation is rated. An arm that cannot survive the cell it lives in has no other specs worth reading, and retrofitting sealing after the fact is not possible; you rebuy.

Controller, I/O, and the fieldbus question

The robot is half the purchase; the controller and how it talks to the rest of the line is the other half, and it is where integration cost hides.

Controller and teach. Each vendor ships its own controller and programming environment (FANUC's R-30iB, ABB's OmniCore/IRC5, KUKA's KR C5, Yaskawa's YRC1000), and standardizing on one vendor across a plant saves real money in spares, training, and integrator familiarity. The teach pendant, the programming language, and the offline tools differ enough that a maintenance team fluent in one is slow on another. This is a quiet but strong argument for platform consistency.

I/O and fieldbus. The robot has to exchange signals with PLCs, safety controllers, vision systems, grippers, and the line. Confirm the controller supports your plant's fieldbus (EtherNet/IP, PROFINET, EtherCAT, PROFIBUS, or DeviceNet on older lines) and has enough digital and analog I/O, or the network card and slots to add it. A robot that speaks the wrong fieldbus needs a gateway, which is cost and a failure point. The broader factory-network picture is in industrial automation, PLC, SCADA, and fieldbus.

Real-time and coordination. Cells that coordinate multiple robots, track a moving conveyor, or synchronize with a press or CNC lean on the controller's real-time behavior and its conveyor-tracking and multi-robot options. If your cell does any of that, confirm the option is available and licensed. The control-loop fundamentals are covered in real-time control systems, and if you are integrating with ROS 2 on the cell side, the ROS 2 guide covers the bridge.

Rule of thumb: Pick the controller ecosystem before the model, and pick it for the plant, not the cell. A second vendor's controller on the floor doubles your spare-parts inventory, your training burden, and your integrator's learning curve, and it rarely pays for the marginal performance that justified it.

Cobot vs industrial arm

The fork that reshapes the whole purchase is whether you buy a fenced industrial arm or a collaborative robot. They solve overlapping problems with opposite tradeoffs, and choosing wrong is expensive either way.

A cobot is force- and speed-limited so it can work next to people without a fence, subject to a risk assessment. That buys you a small footprint, fast redeployment, and easy programming, at the cost of speed and payload: cobots run slower and top out around 3 to 35 kg. A fenced industrial arm runs full speed and full payload behind a guard, which wins on cycle time and cost per part for a fixed, high-rate cell.

The honest decision rule: if the cell is fast, heavy, fixed, and runs high volume, a fenced industrial arm wins on cost per part. If the cell is lower-rate, shares space with people, changes often, or has no room for a fence, a cobot earns its premium through flexibility and floor space. Note that a cobot without a fence still needs a risk assessment, and adding a gripper with sharp edges or running it fast can force you to fence it anyway, at which point you bought a slow industrial arm. The full cobot decision is in how to choose a cobot, and the safety framework for both is in robot safety and functional safety.

Factor	Fenced industrial arm	Cobot
Speed	Full (1 to 4+ m/s)	Reduced when collaborative
Payload	3 to 300+ kg	~3 to 35 kg
Guarding	Fence, light curtains, scanners	Often fenceless after risk assessment
Redeployment	Slower, integrator-led	Fast, often in-house
Cost per part (high volume)	Lower	Higher
Best for	Fixed high-rate cells	Flexible, shared-space, changeover-heavy

Rule of thumb: Volume and speed favor the fenced arm; flexibility and shared space favor the cobot. Do not buy a cobot to save on a fence and then run it fast with a sharp gripper, because the risk assessment will hand you back the fence and you will have paid a premium for a slow robot.

Cost bands and what each buys

Industrial-arm pricing steps by size and capability, and the robot is only part of the cell cost. These bands are for the robot and controller in 2026; the integration multiplier comes in the next section.

Under $30,000: small arms, SCARAs, light cobots. Small 6-axis arms (up to roughly 7 to 10 kg), SCARAs, and entry cobots. This tier handles light assembly, small-part pick-place, dispensing, and light machine tending. The robot is cheap enough that integration dominates the project cost.

$30,000 to $80,000: mid-payload 6-axis, mainstream workhorses. The volume tier: 6-axis arms from roughly 10 to 50 kg payload with 1.4 to 2.5 m reach, the machines that do most welding, machine tending, and general handling. Deltas for packaging and larger SCARAs live here too. Most manufacturing robot purchases land in this band.

$80,000 to $150,000: heavy payload and long reach. Arms from 50 to 150 kg payload and 2.5 to 3.5 m reach, for palletizing, heavy material handling, and large-part welding, plus specialized environmental variants (foundry, cleanroom, wash-down) that carry a premium.

$150,000 and up: very heavy, specialized, and multi-robot. Arms above 150 kg payload (up to 700 kg and beyond for automotive body handling), gantry systems, and multi-robot coordinated cells. The robot is often a modest line item next to the structure, tooling, and controls.

Band	Get	Do not expect	Best for
< $30k	Small 6-axis, SCARA, light cobot	High payload, long reach	Light assembly, small pick-place, dispensing
$30k to $80k	10 to 50 kg 6-axis, delta, large SCARA	Heavy lift, specialized sealing	Welding, machine tending, general handling
$80k to $150k	50 to 150 kg, long reach, env. variants	Body-in-white payloads	Palletizing, heavy handling, harsh environments
$150k+	150 to 700 kg, gantry, multi-robot	A cheap integrated cell	Automotive, heavy industry, coordinated cells

Sort the industrial arm leaderboard by price against payload, reach, and repeatability to see where the value steps fall in the current generation rather than trusting a band chart in the abstract.

Rule of thumb: Buy the size class your payload-at-reach and takt require, then stop. Over-buying reach and payload costs speed and money every cycle; under-buying strands a fixture out of range or faults the arm on inertia. The robot price is the easy part of the number; the cell is the hard part.

Integration and total cost of ownership

The robot is 20 to 40% of a turnkey cell. The rest is the work that makes it do something, and the buyers who compare robot prices and ignore this are comparing the wrong number.

A rule integrators use: the installed cell costs two to three times the robot for a straightforward application, and more for complex vision-guided or multi-robot work. The line items are end-of-arm tooling (grippers, tool changers, force sensors), machine vision and lighting, safety (fencing, light curtains, scanners, safety PLC), part presentation and fixturing, the controls and electrical panel, mechanical guarding, and the engineering and programming labor to design, build, install, and commission it. Fixturing and part presentation quietly eat a large share, because a robot needs the part in a known place.

Total cost of ownership then adds the operating years: energy, maintenance and spare parts (the vendor's spares availability and pricing matter here), operator and maintenance training, software and controller licenses, and eventual retooling for the next product. Uptime and mean time to repair dominate the economics of a production cell, which is why spares availability and local service support are worth paying for even when a cheaper robot's datasheet looks better.

Buy, integrate, or RaaS. Three procurement paths. Buy the robot and hire an integrator for a custom cell, which is standard for anything non-trivial. Buy a pre-engineered work cell (many vendors and integrators sell packaged welding, palletizing, and machine-tending cells) to cut engineering cost and risk for a common application. Or, increasingly in 2026, take Robotics-as-a-Service, a monthly fee for a deployed and maintained cell, which shifts capital to operating expense and moves the uptime risk to the provider. RaaS suits lower-volume users, uncertain product lifecycles, and buyers who want to avoid an integration project, at a higher lifetime cost than owning a well-utilized cell.

Rule of thumb: Budget the cell, not the robot. Aircraft-carrier math applies: the robot is the visible cost and the smaller one. Price tooling, vision, safety, fixturing, controls, engineering, and two years of spares and training, and the robot brand you agonized over is a rounding difference next to the integration.

The vendor and ecosystem landscape

The industrial-arm market is concentrated, and picking a vendor is picking an ecosystem of controllers, spares, integrators, and support you live with for a decade.

The big four. FANUC (Japan) is the volume leader, yellow arms everywhere, deep in automotive and machine tending, known for reliability and a huge installed base and spares network. ABB (Switzerland/Sweden) is strong across general industry, welding, and packaging, with the OmniCore controller and RobotStudio offline software. KUKA (Germany, Midea-owned) is prominent in automotive and heavy handling, orange arms, with a strong European integrator base. Yaskawa Motoman (Japan) is a leader in arc welding and handling, with a large range and strong motion control heritage.

Strong specialists and regional leaders. Kawasaki (Japan) covers general handling, welding, and palletizing with a long automotive history. Mitsubishi Electric offers compact 6-axis and SCARA arms tightly integrated with its own PLCs and drives, attractive if your plant is already Mitsubishi automation. Staubli (Switzerland) is the premium choice for cleanroom, pharma, and high-precision applications, with excellent sealing and accuracy. Epson and Omron lead in SCARA for electronics and precision assembly; Epson in particular is a SCARA volume leader. For high-speed delta packaging, ABB (FlexPicker), FANUC, and Codian are common. Universal Robots, Techman, Doosan, and FANUC's CRX line lead the cobot segment discussed above.

How to choose among them. For a first robot, weight the local integrator and service network and the fieldbus fit with your existing controls at least as heavily as the spec sheet, because a well-supported robot from a vendor with a strong local integrator beats a marginally better robot you cannot get serviced. For a plant standardizing a fleet, pick one primary vendor for spares, training, and integrator familiarity, and treat a second vendor as an exception you justify per cell. Match SCARA and precision-assembly needs to Epson, Staubli, Mitsubishi, or Yaskawa; match heavy handling and welding to FANUC, ABB, KUKA, Yaskawa, or Kawasaki.

You can filter the industrial arm leaderboard by vendor, payload, reach, and repeatability to build a like-for-like shortlist before you talk to a sales team, which keeps the comparison honest.

A repeatable selection process

Put it together into a checklist you can run for any purchase, first robot or fleet addition.

1. Write the task in one sentence with a rate, including the part, the motion, and the takt. "Load a 6 kg blank into a CNC and unload the finished part with a flip, every 22 seconds." If you cannot, stop here until you can.
2. Pick the architecture from the motion: SCARA for planar pick-place, delta for high-speed light picking, cartesian for long strokes and large parts, 6-axis for orientation and dexterity.
3. Map the part flow onto the work envelope. Overlay infeed, machine, fixtures, and outfeed on the envelope diagram and fix the reach the cell actually needs.
4. Compute payload at reach with tooling. Part plus full end-of-arm tooling, at the combined center of gravity, at your worst-case reach and orientation, checked against the payload diagram and the vendor's load tool, with 20 to 30% margin.
5. Set the repeatability from the tightest process tolerance, with margin, and no tighter. Ask about absolute accuracy if you program offline or use vision.
6. Specify the environmental variant and mounting (IP rating, foundry/cleanroom/wash-down, floor/wall/ceiling) as a hard filter.
7. Confirm the controller and fieldbus fit your plant's automation, and check I/O count and the options you need (conveyor tracking, multi-robot, safety).
8. Decide cobot vs fenced arm on volume, speed, shared space, and changeover frequency, then run the safety risk assessment.
9. Simulate the actual cycle with your path and payload in the vendor's offline tool to confirm you hit takt with margin.
10. Build the real budget: robot plus tooling, vision, safety, fixturing, controls, engineering, and two years of spares and training, or price the RaaS alternative. Shortlist on the leaderboard and validate with the integrator before you commit.

Run this in order and the shortlist narrows to two or three models across one or two vendors you can buy with confidence. Skip the task and the payload-at-reach steps and you will do what most first-time buyers do, which is fall for a payload number and discover the constraint on the floor.

Frequently asked questions

How much does an industrial robot arm cost? The robot and controller run roughly $25,000 to $60,000 for a mainstream mid-payload 6-axis arm, under $30,000 for small arms and SCARAs, and $80,000 to $150,000-plus for heavy or specialized models. The installed cell typically costs two to three times the robot once you add tooling, vision, safety, fixturing, controls, and engineering, so budget the cell rather than the robot. For low volumes or uncertain product lifecycles, Robotics-as-a-Service turns that capital into a monthly fee.

6-axis or SCARA: which do I need? Pick by motion. A SCARA is faster and cheaper for planar pick-place and top-down insertion and holds tighter repeatability (down to plus or minus 0.01 to 0.02 mm), but it cannot tilt or reorient a part. A 6-axis arm gives full orientation freedom for welding, machine tending, and any task that approaches the part from varying angles, at higher cost and slower cycle for the same planar move. If your part moves in a plane and drops straight down, SCARA; if it needs orientation, 6-axis.

Why is payload at reach different from the headline payload? The wrist rating is a peak at an ideal center of gravity and short reach. Usable payload falls off toward the edge of the envelope, drops with any center-of-gravity offset from long tooling, and is limited by inertia at speed. A robot rated 20 kg at the wrist may only carry 12 to 14 kg at full reach with a 200 mm gripper offset. Always rate the part plus tooling at your actual reach and orientation, then add 20 to 30% margin.

What repeatability do I actually need? Match it to your tightest process tolerance with margin, and no tighter. Palletizing is happy at plus or minus 0.1 to 0.5 mm, machine tending and welding at plus or minus 0.05 to 0.1 mm, general assembly at plus or minus 0.02 to 0.05 mm, and precision electronics assembly at plus or minus 0.01 to 0.02 mm. If you program offline or use vision, ask about absolute accuracy too, because it is looser than repeatability and it is the number that matters there.

Should I buy a cobot or a fenced industrial arm? Buy the fenced arm if the cell is fast, heavy, fixed, and high-volume, because it wins on cycle time and cost per part. Buy the cobot if the cell shares space with people, changes often, runs lower rate, or has no room for a fence, because it earns its premium on flexibility and floor space. Remember that a cobot still needs a risk assessment, and running it fast or with a sharp gripper can force you to fence it anyway. See how to choose a cobot.

Which robot brand is best? Mission fit, local service, and controller and fieldbus consistency matter more than brand. FANUC, ABB, KUKA, and Yaskawa are the volume leaders for general handling and welding; Epson, Staubli, and Mitsubishi lead precision SCARA and cleanroom work; Kawasaki and others are strong regional and application specialists. For a first robot, weight the local integrator and spares network heavily; for a fleet, standardize on one primary vendor. Filter the leaderboard by your ranked specs to see the real shortlist.

How long does integration take, and can I do it myself? A straightforward cell (palletizing, simple machine tending) commissions in weeks with an integrator or a pre-engineered work cell; a complex vision-guided or multi-robot cell can take months. In-house integration is realistic for cobots and simple pick-place if you invest in training, and it is a stretch for fenced high-speed cells with vision and safety systems, where an integrator's experience pays for itself. Pre-engineered work cells and RaaS both cut the engineering risk if you lack in-house robotics staff.

Do I need machine vision? Only if the part arrives in an unknown position or orientation, or you need to inspect as you handle. If fixturing presents the part in a known place every time, you may not need vision, and mechanical fixturing is often cheaper and more reliable. If parts come loose in bins or on a belt, vision (2D for planar location, 3D for bin picking) is what makes the cell possible, at added cost and tuning effort. See machine vision.

What environmental rating should I specify? Match it to the cell. Standard IP54/65 for dry assembly and handling, IP67 or a coolant-rated wrist for machine tending in spray, wash-down and food-grade for food and pharma, foundry-grade for die casting and forging, cleanroom variants for semiconductor and pharma, and ATEX for paint and solvent atmospheres. Specify it up front, because you cannot retrofit sealing and buying a standard arm for a hostile cell is a repair contract you signed by accident.