§3 xArm 6
Major Components
The parts of the system, what each one does, and how they connect.
Start Here
This section names the parts of the system, says what each one does, and shows how they connect. Every tier below starts from the same three facts.
12
pins on the tool connector1
6
pins on the arm cable's connector: ground and two RS-485 pairs2
AC or DC
the two control boxes in the manual's hardware list3
- The system is more than the arm. UFACTORY's manual lists a control box, an emergency stop button, cables, a mounting tool and end effectors beside it3. The end effector mounts on the wrist and carries the tool that does the work4.
- The control box is the core of the system: it holds the arm's control system4.
- The emergency stop button is on the control box5.
S6 in one line: S6 is the xArm 6 arm that handles parts after processing, routing them to inspection, rework or shipping6.
Look Back
A question from earlier on, to keep it fresh. Skip it if you like; nothing depends on it.
Choose your depth
1Beginner
The Parts You Can See
For: Anyone with no robotics background: a visitor, a new operator, a manager
Kind of task: Recognize and recall, with plain-language explanations and pictures
In this part you name each part of the system and find the one button everyone near the arm must be able to reach. No robotics background is needed.
What the System Is Made Of
- UFACTORY's manual lists the hardware as the arm, an AC control box, a DC control box, an emergency stop button, a power cable, a communication cable, a mounting tool, and end effectors: a force-torque sensor, the BIO Gripper, the Vacuum Gripper and the xArm Gripper3.
- A control box is included with the arm by default7.
The Arm
- The arm is made up of a base and rotary joints. Each joint is one degree of freedom, and they are numbered from the bottom up: Joint 1, Joint 2 and so on8.
- The xArm 6 has six of these joints. The last one is the tool side, where a tool such as a gripper connects8.
- The arm is made of aluminum and carbon fiber9.
The Control Box
The control box is the core of the system: it holds the arm's control system4.
- It has three lights. ROBOT PWR is on when the arm has power, STATE flashes when the controller has power, and LAN is on when the arm is communicating normally10.
- The emergency stop button is on the control box5.
- That is why the manual says the control box must sit outside the arm's working range, where the button can be pressed in an emergency11.
The Tool on the End
- The end effector mounts on the front of the wrist. It carries the tool, such as a gripper or a vacuum gripper, that does the work4.
- UFACTORY's official accessories are the Gripper, the Vacuum Gripper, the BIO Gripper G2, a six-axis force-torque sensor and a linear motor12.
- At S6, the arm's attachment has five suction cups13.
Brakes in the Joints
The joints have brakes inside. When the power is lost, they hold the arm in its pose14.
The Software
Check Yourself
Answer, then check. Each option has its own feedback, and nothing is scored.
2Novice
How the Parts Work Together
For: Someone who will work near or with the cell: operator, trainee technician
Kind of task: Explain and sequence: put steps in order, match parts to their functions
In this part you follow a command from a computer all the way to the gripper, and learn the handful of rules that look after the arm and its cables. It is for someone who will work near or with the cell.
From a Click to a Moving Gripper
This platform pieces together the path a command takes from UFACTORY's descriptions of each part, so the path is Inferred, and its reasoning is printed with the record21.
- A computer, running Studio or a program using the SDK, sends the command over Ethernet to the control box, using UFACTORY's private TCP protocol2122.
- The control box runs UFACTORY Studio2116.
- The control box reaches the arm through two separate cables, one for power and one for communication2123.
- The cable connector lists separate RS-485 lines, one for the arm and one for the tool2124.
- The gripper at the flange gets its power and control signals from the 12-pin tool connector211.
The flow gives no voltage for the power cable. The intermediate tier explains why.
Two Kinds of Control Box
- The manual's hardware list has both an AC control box and a DC control box3.
- The AC box accepts 100–240 V AC at 50/60 Hz25. The DC box accepts 24–72 V DC26.
What Studio Holds, and What Is Missing
- In Studio you can set parameters, move the arm in Live Control, and build a motion by dragging and dropping Blockly code blocks15.
- No dedicated teach pendant is documented for the xArm 6. The manual and the product page describe programming it through Studio, the SDKs and hand teaching27.
- In manual mode you can drag the joints by hand. Teach sensitivity runs from level 1 to 5, and the higher the level, the less force it takes28.
Choosing and Fitting a Tool
- In Studio's End Effector setting you choose the tool that is fitted. The list includes the Gripper, the Vacuum Gripper, the BIO Gripper and the Robotiq 2F-85 and 2F-140 grippers, among others. Any tool that is not on the list is set as "Other"29.
- The Gripper in the manual's specifications has an 84 mm working range, a maximum clamping force of 30 N and weighs 802 g30.
- The Vacuum Gripper (AS1200) has a payload of up to 5 kg and weighs 610 g31.
- Installing the end effector is the fifth and last of the manual's installation steps32.
The Tool at S6
- S6 uses an attachment with five suction cups13.
- S2's and S6's suction tools are basically the same attachment: a rounded mount with the cups attached as one unit. S6's tool uses all five ports on the mount; S2's uses just one33.
Looking After the Arm and Its Cables
- Use only the arm's original cable, and do not use the arm where that cable has to bend. For a longer or flexible cable, ask the supplier34.
- The manual says to place the controller between 0.6 m and 1.5 m high35.
- The arm's shell is carbon fiber. It can be wiped with 95% alcohol or 70% isopropanol, as long as no liquid gets into the joints36.
Check Yourself
Answer, then check. Each option has its own feedback, and nothing is scored.
3Intermediate
Installing and Connecting the Parts
For: Someone who will set up, program or maintain the arm: technician, student engineer
Kind of task: Apply: work through written scenarios that need a decision (which mode, which setting, what to do about this error), with feedback on each choice
In this part you work through what installing the system involves: power, cables, the tool flange and what the tool end offers, and the rules for storage, the brakes and the emergency stop. It is for someone who will set up, program or maintain the arm.
Power into the Control Box
- The AC control box takes mains power through a standard IEC C20 inlet, with an IEC C19 cable42.
- The manual's power-supply section says the box takes 100–240 V AC and that a switching power supply inside turns it into 12 V and 48 V DC, for the box itself and the arm43.
- The manual's specification table says otherwise: it gives the arm's input as 24 V DC, 20.8 A, and the AC controller's output as the same44. So the manual disagrees with itself on what the AC control box supplies45.
- The DC control box has VP+ (24–72 V DC in), GND and PE terminals. PE connects to the housing for leakage protection and is not a must46.
- The power cut-off is a plug and socket, so the manual recommends a switching device with enough breaking capacity, such as an air switch with 400 V AC insulation voltage and 10 A rated current47.
Cables
- The manual lists the arm's power cable and communication cable separately, and both plug into the arm and into the control box23.
- The cable connector's table lists six pins: GND on pins 1 and 4, the arm's RS-485 A and B on pins 2 and 3, and the tool's RS-485 A and B on pins 5 and 648. The same pin definition is given for the AC and DC controllers2.
- I/O cables from the control box to other equipment must not be longer than 30 m, unless extension testing shows a longer run works49.
The Tool Flange and Connector
- The manual gives the end flange as DIN ISO 9409-1-A50/63 (M6*6)50.
- A 12-pin female aviation-style socket at the tool side supplies power and control signals for grippers and sensors1. It supplies 24 V (20–30 V) at up to 1800 mA51.
- The product page gives the tool end's I/O as 2 digital inputs, 2 digital outputs, 2 analog inputs and 1 RS-485 port, and the manual's pin table has matching signals52.
The Battery, and the Brakes
- The arm has a built-in battery. If it is not used for 3 months or more, the manual says to power it on for 6 hours every 3 months to charge it, without enabling the arm41.
- Studio can unlock a single joint so it can be turned by hand. Someone must support the arm while the brakes are released, to stop it falling, and every joint must be locked again afterwards53.
What the Emergency Stop Does
- Pressing the button sends the control box a command for software deceleration, which stops the arm and clears its cached commands. Power to the arm is removed within 300 ms5.
- When it is pressed, the arm's posture brakes slightly and falls. The manual says the e-stop should not be used as a risk-reduction measure54.
- The manual lists the e-stop button and the emergency input (EI) as Stop Category 1, and the safeguard stop input (SI) as Stop Category 255.
- These descriptions do not fit together: power removed within 300 ms, but a Category 1 stop that decelerates with drive power on for up to 885 ms. The contradiction card sets out both sides56.
Gripper Figures You Will Be Asked For
- The Gripper in the manual's specifications runs on 24 V DC (28 V absolute maximum), with 1.5 W quiescent power and 1.5 A peak current57.
- It talks RS-485, with programmable position and speed and position feedback58. Its protocol is disputed: the manual's table says Modbus TCP, while the product page says Modbus RTU over RS-48559.
- The manual and the product page list the BIO Gripper G2, the force-torque sensor and the linear motor by name only, with no specifications60.
- S6's own attachment is a suction tool rather than the xArm Gripper: five suction cups13.
Which xArm 6 Is It?
- UFACTORY's serial-number guide tells an xArm's model from its serial number: the axis-count letter is S, I or F for the xArm 7, 6 and 561.
- UFACTORY distinguishes four versions of the xArm 6 by serial number. This project's advice: read the arm's serial number before relying on any figure the sources disagree on, such as its weight or the Joint 2 and Joint 3 ranges62.
Check Yourself
Answer, then check. Each option has its own feedback, and nothing is scored.
4Expert
Electrical and Kinematic Detail
For: Someone who designs, integrates or changes the cell: integrator, engineer, agent developer
Kind of task: Analyze and decide: weigh trade-offs, resolve contradictions, critique a configuration
In this part you read the arm's geometry, its model numbers and hardware versions, and the electrical detail of its inputs, outputs and tool pins, and learn where the detail in the UFACTORY sources runs out. It is for someone who designs, integrates or changes the cell.
The Arm's Geometry
UFACTORY's modified D-H parameters give the xArm 6's link lengths in millimeters, and the xarm_ros2 kinematics file gives its joint origins in meters6566.
- Joint 1: d = 267 mm. The ROS file puts the Joint 1 origin at z 0.267 m6768.
- a2 = sqrt(284.5² + 53.5²), which works out to 289.48661 mm; UFACTORY's notes print 289.48866 mm, 0.002 mm more6970. The ROS file instead gives the Joint 3 origin as x 0.0535 m, y -0.2845 m71.
- Joint 4: d = 342.5 mm and a = 77.5 mm; in the ROS file, x 0.0775 m, y 0.3425 m7273.
- Joint 6: d = 97 mm and a = 76 mm; in the ROS file, x 0.076 m, y 0.097 m7475.
- The notes also give the joint-angle offsets between the mathematical and mechanical zero positions: T2_offset = -1.3849179 rad (-79.34995°), and T3_offset = +1.3849179 rad69.
Model Numbers and Hardware Versions
- The online manual says it applies to models XF1305, XI1305 and XS1305. UFACTORY's displacement test lists the xArm 6 as XI1305, and its serial-number guide reads SN XI130506D43A0A as an xArm 6, model 476.
- UFACTORY publishes separate mass parameters for four versions of the xArm 6, Model 1 to Model 4, and tells them apart by serial number. The manual says the 1305 model is model 477.
- So an arm's version decides which mass parameters apply, and it has to be read from its serial number62.
Inside a Joint
UFACTORY's product page names only harmonic drives and servomotors for the joints78.
Motor model and rating, harmonic-drive ratio, encoder type and resolution, and joint-module sizes are not in the manual or the product page. Unlike the 850's page, the xArm page gives no encoder resolution78.
The Controller's Inputs and Outputs
- The control box has two fixed safety inputs, an emergency stop input and a protective stop input. All safety I/Os come in pairs and must be kept in two separate branches79.
- The configurable inputs CI0–CI7 support Stop Moving, Safeguard Reset and Reduced Mode. The general inputs DI0–DI7 do not80.
- The digital outputs are NPN open-collector or open-drain, rated 0–100 mA, with no current protection81.
- The internal 24 V I/O supply delivers up to 1.8 A and is the default. An external 24 V supply of up to 3 A can be connected instead82.
- Analog inputs and outputs work at 0–10 V with 12-bit resolution, and are not isolated from the control box83.
The Tool Connector, Pin by Pin
- Pins 1–2 carry +24 V, pins 3–4 are 0 V, pins 5–6 are User RS-485 A and B, pins 7–8 are tool outputs TO0 and TO1, pins 9–10 are tool inputs TI0 and TI1, and pins 11–12 are analog inputs AI0 and AI163.
- Tool outputs are NPN open-collector, sinking up to 100 mA, with no current protection84.
- Tool inputs have a pull-down resistor, so a floating input always reads low. Logic low is at most 1.0 V, logic high at least 1.6 V, and the inputs are rated -0.5 to 30 V85.
- Tool analog inputs are non-differential, accept -0.5 to 3.3 V in voltage mode, have 12-bit resolution and have no over-voltage protection86.
- Third-party RS-485 devices can be driven through the tool port; UFACTORY's own tool uses ID 9. Standard Modbus RTU tools are set up under the Studio page that the xArm manual calls Settings-Externals-Modbus RTU, a section the Studio manual, as read on 2026-10-13, heads RS-485; others are driven with getset_tgpio_modbus_data using transparent transmission6487.
The Vacuum Gripper in Figures
The Vacuum Gripper (AS1200) in the manual gives -55 kPa and more than 4 L/min. It runs on 24 V DC (28 V absolute maximum), draws 20 mA quiescent and 500 mA peak, uses digital I/O as its communication mode, and feeds back air pressure as low or normal88.
Check Yourself
Answer, then check. Each option has its own feedback, and nothing is scored.
Not settledOpen Questions · 10
What the sources do not settle for this section. Nothing here is papered over with a plausible number.
- Kind: Gap
No dedicated teach pendant for the xArm 6 is documented in the xArm manual or the product page: they describe programming through the browser-based UFACTORY Studio, the SDKs and hand teaching.
See reference 27 - Kind: Contradiction
Sources disagree on how the xArm AC control box powers the arm: the manual's controller chapter says its internal supply converts 100-240 V AC into 12 V and 48 V DC for the control box and the arm, while the common specification table gives the arm's input as 24 V DC, 20.8 A and the AC controller's output as 24 V DC, 20.8 A.
See reference 44 - Kind: Contradiction
The xArm manual disagrees with itself on what the AC control box supplies: its specification table (and the product page) give the AC controller's output as 24 V DC, 20.8 A, but its 3.2.2 Power Supply text says the internal switching power supply converts 100–240 V AC into 12 V and 48 V DC, which powers the control box and the robotic arm.
See reference 45 - Kind: Contradiction
The xArm manual describes the Control Box emergency stop in ways that do not fit together. Section 2.1.2 says the arm's power supply is removed within 300 ms and that pressing the button powers off the xArm; section 3.2.2 says the button allows the user to cut off the arm's power in the shortest time possible. Section 7.9 says the same button is Stop Category 1, which decelerates the robot 'with drive power on', and section 7.10 gives Stop Category 1 stopping times of 521 to 885 ms. The manual does not explain how power removal within 300 ms fits a powered deceleration lasting up to 885 ms.
See reference 56 - Kind: Contradiction
Sources disagree on the xArm's end-effector communication protocol: the manual's common specification table says Modbus TCP, but the product page says Modbus RTU over RS-485, and the manual's own Tool RS485 section configures standard Modbus RTU end effectors. The manual's Gripper table likewise pairs RS-485 communication with a 'Modbus TCP' protocol.
See reference 59 - Kind: Gap
No specification for the BIO Gripper G2, the 6-axis force/torque sensor or the linear motor (payload, force range, resolution, stroke) was found in the xArm manual or the product page; only their names are listed.
See reference 60 - Kind: Gap
Per-joint component data for the xArm 6 (motor model and rating, harmonic-drive ratio, encoder type and resolution, joint-module sizes) is not published in the xArm manual or the product page; the product page names only harmonic drives and servomotors and, unlike the 850's page, gives no encoder resolution.
See reference 78 - Kind: Contradiction
UFACTORY's documents give one page of UFACTORY Studio two names. The xArm manual says a standard Modbus RTU end effector is debugged under 'Settings-Externals-Modbus RTU'. The Studio manual's Settings chapter, as read on 2026-10-13, heads its section 7.2.5, under 7.2 Externals, 'RS-485'; until that date the section was headed 'Modbus RTU'. UFACTORY's release note for Studio V2.8.2 names the page 'Settings - Externals - RS-485'; no fetched source says from which Studio version the page carries that name.
See reference 87 - Kind: Gap
No Ethernet connection, camera port, force-torque sensor interface or user button at the xArm 6's tool end is described in the xArm manual or the product page; the product page lists the end-effector I/O as 2 DI, 2 DO, 2 AI and 1 RS-485.
See reference 98 - Kind: Contradiction
The xArm manual's specifications page has given two thread sizes for the xArm's end flange: 'DIN ISO 9409-1-A50/63 (M5*6)' until 2026-10-15, and 'DIN ISO 9409-1-A50/63 (M6*6)' as the page read on 2026-10-15 (publisher's commit 0d30e6b, in English and Chinese). The current reading is spec-582; spec-573 is kept as history.
See reference 99
ProvenanceReferences · 99
Each number in the text points here. Every entry states its confidence class in words and keeps its evidence one click away. How to read the labels.
Key to the badges
- Confidence: Verified
- A manufacturer or IntelliMake document says so, or it was observed directly. It does not mean anyone measured it at S6.
- Confidence: Inferred
- Reasoned from Verified facts. The reasoning is printed with the record.
- Confidence: Assumed
- Plausible but untested. The record says how it would be checked.
- Kind: Gap
- Not known. No figure or answer is given in its place.
- Kind: Contradiction
- Sources disagree. Both sides are shown, and the site does not pick one silently.
- Kind: Recommendation
- Project advice drawn from the records it cites. Not a fact about the machine and not a confidence class, so the filter never hides it.
- Awaiting cell access
- Awaiting cell access: could be confirmed or corrected once the physical S6 cell can be observed.
- This project's simulation and agent design, not the physical cell
- This project's simulation and agent design, not the physical cell.
Image Credits
- 3D model: © 2018 UFACTORY Inc., BSD-3-Clause, from UFACTORY Inc. (xArm-Developer/xarm_ros2). License text · Source
Sources for This Section
- 0.1 mm Displacement Test for 850 and xArm 6 (support article) · UFACTORY (manufacturer)
- CODE_SESSION 01 — xArm 850 Interactive Learning Platform (project specification) · Derek Stringfellow (project owner)
- IntelliMake Phase 1 Factory: Autonomous Production Demonstrator (infographic) · IntelliMake.org (IntelliMake)
- Kinematic and Dynamic Parameters of xArm Series: telling the model by SN (support article) · UFACTORY (manufacturer)
- Kinematic and Dynamic Parameters of xArm Series: telling the xArm model from the SN (UFACTORY support article) · UFACTORY (manufacturer)
- Kinematic and Dynamic Parameters: xArm 6 (support article) · UFACTORY (manufacturer)
- Owner statements from 2026-09-24 onward (verbatim; S40 and later) · Derek Stringfellow (project owner)
- UFACTORY 850 product page · UFACTORY (manufacturer)
- UFACTORY Release Note v2.8.2 · UFACTORY (manufacturer)
- UFACTORY Studio product and download page · UFACTORY (manufacturer)
- UFACTORY Studio User Manual (online), 1. Preface · UFACTORY (manufacturer)
- UFACTORY Studio User Manual (online), 2. Glossary · UFACTORY (manufacturer)
- UFACTORY Studio User Manual (online), 4. Live Control · UFACTORY (manufacturer)
- UFACTORY Studio User Manual (online), 7. Settings · UFACTORY (manufacturer)
- UFACTORY Studio User Manual, 7. Settings, as it read until 2026-10-13 (publisher's repository, commit 533b75d) · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 1. Safety · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 2. Hardware Installation · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 3. Controller Electrical Interface · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 4. Robotic Electrical Interface · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 5. Maintenance and Inspection · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 7. Production Information · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 8. Technical Specifications · UFACTORY (manufacturer)
- UFACTORY xArm Hardware Manual (online), 8. Technical Specifications, as it read until 2026-10-15 (publisher's repository, commit e474ecb) · UFACTORY (manufacturer)
- UFACTORY xArm product page · UFACTORY (manufacturer)
- xarm_ros2 (branch humble), xarm_description/config/kinematics/default/xarm6_default_kinematics.yaml · UFACTORY (manufacturer)
IntelliMake diagrams are redrawn as native figures, © IntelliMake.org. UFACTORY does not endorse this platform.