6-axis robot arms: a specification and setup checklist

A six-axis robot arm can place its tool at a chosen position and angle within its working space. That flexibility is why six axes are so common. It does not tell you whether a particular arm can carry your tool, reach every point in your task, repeat the movement closely enough or fit safely into the place where it will work.

This checklist helps you compare arms around the job. The figures below are manufacturer specifications from the linked pages, not results from Robodromo testing, and each applies to the stated model and conditions.

What six axes mean

Each axis is a rotating joint. Broadly, the first three move the wrist around the working space and the last three orient the tool, so the arm can approach a point from more than one direction.

Axis count only describes the mechanism. Two six-axis arms can differ greatly in payload, reach, stiffness, software and support, and a joint that cannot turn far enough may block an approach angle your task needs.

Three manufacturer examples

These examples show how widely six-axis designs vary. They are not a ranking or a recommendation.

• Elephant Robotics myCobot 280 M5: 6 degrees of freedom, 250 g payload, 280 mm working radius and ±0.5 mm repeatability, according to the manufacturer's parameter table. It uses M5Stack and ESP32-based control hardware.
• Niryo Ned3 Pro: a 6-axis arm listed with a 500 g payload measured at a 20 mm tool centre point offset, 500 mm reach and ±0.3 mm repeatability on Niryo's product page, which also lists block-based programming in NiryoStudio, with Python and ROS access.
• Unitree Z1: 6 axes, 740 mm reach and repeatability of around 0.1 mm, with 2 kg payload for Z1 Air and at least 3 kg for Z1 Pro. Unitree's specification page notes that accuracy varies greatly with test conditions and that position control stiffness is low unless the control mode is optimised.

Read the footnotes as carefully as the headline numbers. For more on the Z1, see our Unitree Z1 overview.

Payload: count everything on the flange

Payload is the total load on the tool flange: gripper, adaptor plate, cables or vacuum parts, and the heaviest object held. A 500 g payload does not mean a 500 g object if the gripper weighs 200 g.

Position matters as well as mass. Universal Robots' manual describes setting both the payload and its centre of gravity in the controller. A long tool or an off-centre object increases the load on the joints, so ask the supplier to check your actual tool, offset and object against the rated conditions.

Reach: check the whole motion

Maximum reach is a single radius. Points near that edge may only be reachable at certain angles, points close to the base can be awkward, and the tool length changes the useful envelope.

Map the start, pick, place and return positions with the orientation needed at each, plus clearance around fixtures, conveyors and people. Ask for the motion to be simulated or demonstrated with your layout.

Repeatability is not accuracy

Repeatability is how closely an arm returns to a taught position. Accuracy is how closely it reaches a position defined by coordinates, for example from a drawing or camera. An arm can be highly repeatable yet offset from where you expected. If your task depends on calculated positions or vision guidance, ask how accuracy and calibration will be handled and checked.

Programming, integration and support

The arm is one part of a working cell. Confirm how it will be programmed, which interfaces and software versions are supported and what connects it to your grippers, sensors or conveyors.

• Who writes and maintains the program?
• What training is included, and for whom?
• What routine maintenance does the manufacturer specify?
• Who diagnoses faults, and how are spare parts supplied?

Collaborative does not mean no assessment

A collaborative robot is designed to work closer to people, but each application still needs its own risk assessment. HSE research report RR1214 notes that in collaborative applications safety relies on software configuration and parameter settings rather than physical separation by guards, and that tools can add hazards. A sharp or heavy tool, a fast movement or a pinch point can change the risk completely.

In Great Britain, PUWER requires work equipment to be suitable for its intended use, maintained, and used only by people with adequate information, instruction and training. This is Great Britain guidance; other jurisdictions have their own requirements. A competent person should assess each application before use.

Budget for the working package

Price the complete arrangement: arm, controller, tool, mounting, any guarding or sensing the risk assessment requires, software, integration, training and support. Keep one-off and recurring costs separate.

Before ordering, agree written acceptance tests covering the task, objects, cycle, positions, tolerances and how many attempts must succeed, who runs the test and what happens if it fails.

Next step

Compare options in our robot arms and manipulation collection, read our FAQs or tell us about your task. Configuration, price, delivery and support must be confirmed in writing before any order.

Sources

• Elephant Robotics: myCobot 280 M5 parameters
• Niryo: Ned3 Pro
• Unitree: Z1
• Universal Robots: payload settings
• HSE RR1214 (2024)
• HSE: PUWER overview

Original ROBODROMO editorial graphic. A buying checklist, not an operating or safety procedure. Sources checked 8 October 2026; confirm specifications with the manufacturer for your exact configuration.