A robotic arm is defined less by its appearance than by three numbers: payload, reach and repeatability. Everything else — the number of axes, the mounting, the controller — follows from the task the arm has to perform.
Configurations
- Articulated — the general-purpose 6-axis arrangement; the widest range of applications.
- SCARA — horizontal arm for fast, precise assembly and pick-and-place.
- Delta — parallel-link design for very high speed over a small workspace.
- Cartesian and gantry — linear axes for large envelopes and heavy loads.
- Collaborative — force- and speed-limited arms designed to share space with people.
The selection figures
- Payload — including the weight of the gripper and any cabling; the rated figure is at the wrist, not at the tool.
- Reach — must cover the working envelope with margin, and payload falls as reach extends.
- Repeatability versus accuracy — repeatability is the figure quoted, and it is not the same as absolute accuracy.
- Cycle time — determined by the arm dynamics and the mass it is carrying.
- Mounting and environment — floor, wall or ceiling; IP rating for washdown or dusty areas.
The cost that is not on the datasheet
The integration is usually larger than the arm: guarding, safety-rated control, end-of-arm tooling, vision, and the engineering to make the cell productive. A cheaper arm that is difficult to integrate is not cheaper.
Spares and life cycle
Arms are long-lived, but reducers, harnesses, encoder batteries and controller boards wear. Establish the spare-part situation before purchase, and confirm that the controller backup and calibration procedures are documented — losing the mastering data turns a routine repair into a full recalibration.
References we have recently quoted in this category
E290B005 BLJS1002521 564-4927 1S60907350422000 586204U001 1S61011291101200 1S61401230000112 KRA-1009 BD4241 W2E142-BB01-01 JOYH100 3363120961 SC132GS 21460-1Z600 SCP460C2 90BF006 AMB150-312000-000 MC3336-7240 5109643 AT1634AS22 DTSL-2N BD-SC-2410 HG123T-D48 YTK-SF2 HOA2007-001 DX220LC-9C S4S-149380 WK0920702 MRC3100 H1P100RBAA5C2N-1 1S60907291101100 Kc868-H32b ITY3-TW030B BMHFi-6/23B DAT4531A DCN890P2 SVL75-3 LRBS2-702M MTZ1-630A TY04221-20341-71
Need a specific reference? Send the exact number to [email protected] with quantity and target date — we reply with sourcing options, equivalent/replacement candidates, condition and lead time.
Related reading
- Obsolete PLC, Sensor & Motor Parts: A Cross-Reference Workflow
- MRO Spare Parts Management
- Spare Parts Management: Principles and Practice