OPC UA Server

This guide describes how to connect to the Spin Robotics OPC UA server and consume tightening results. Unified Automation UAExpert is used as the reference client throughout.

Prerequisites

• UAExpert installed (available from unified-automation.com)

• Network access to the device running the Spin Robotics OPC UA server

• Default server endpoint: opc.tcp://<host>:4840

Connecting to the Server

1. Open UAExpert.

2. In the Project panel (top-left), right-click Servers and select Add Server…

3. Enter the server endpoint URL, e.g., opc.tcp://spinbridge.local:4840.

4. Click OK. The server appears under Servers in the project tree.

5. Double-click the server entry (or right-click → Connect) to establish the connection.

Once connected, the Address Space panel (bottom-left) populates with the server’s node tree:

Objects
└── TighteningSystem          (ns=1;i=5003)
    ├── Identification
    ├── AssetManagement        (ns=1;i=5005)
    └── ResultManagement       (ns=1;i=5011)
        └── Results
            └── LatestResult

Browsing Asset Information

The AssetManagement node exposes the controller and tool identities.

1. In the Address Space, expand TighteningSystem → AssetManagement.

2. You will find two device nodes: SpinBridge (controller) and SpinTool (tool).

3. Click a node to inspect its attributes in the Attributes panel on the right — manufacturer, serial number, firmware version, and hardware revision are all listed there.

Asset data is updated automatically when the device connects and reports its identity.

Subscribing to Result Events

The recommended way to receive results is to subscribe to events on the ResultManagement node. This ensures every result is delivered without risk of missing operations that complete within a polling interval.

Setting Up the Event View

1. In UAExpert, open the Event View document tab. If not already open, add it via Document → Add Document → Event View.

2. In the Address Space, navigate to TighteningSystem → ResultManagement (ns=1;i=5011).

3. Drag the ResultManagement node into the Configuration pane of the Event View.

4. UAExpert will display a list of available event types. Enable SimpleEvents > ResultReadyEventType and select the fields you want to monitor — at minimum Result, the complete JoiningResultDataType payload.

5. Click Apply (or the green play button in the toolbar).

The server will now push a notification each time a joining operation completes.

Reading Incoming Events

Each event appears as a new row in the Events View. Select a row to inspect the full result payload:

• Metadata — result UUID, overall pass/fail evaluation, timestamps.

• overallResultValues — final torque (Nm), final angle (°), and final insertion depth (mm), each with measured value, target, limits, and individual evaluation.

• associatedEntities — traceability data: tool ID, program, and any external identifiers (serial number, joint ID, batch, etc.) attached by the robot program.

• Trace data — time-series channels (torque, angle, speed, force, insertion depth) captured during the operation.

UAExpert with an active event subscription. The bottom pane displays an incoming result with the associatedEntities array expanded, showing the entity fields (entityId, isExternal, entityType, description).

Polling the Latest Result

If event subscriptions are not available in your client, you can poll the LatestResult variable instead.

1. In the Address Space, navigate to TighteningSystem → ResultManagement → Results → LatestResult.

2. Drag the node into the Data Access View.

The variable updates each time a new result is stored.

Hint

Polling risks missing results if two operations complete within a single poll interval. Event subscription is strongly preferred for production use.

Understanding the Result Structure

Metadata

Field	Description
resultId	Unique UUID for this result
resultEvaluation	Overall outcome: OK or NOT_OK
processingTimes	Start and end timestamps of the operation
associatedEntities	Traceability references — see below

Measured Parameters (overallResultValues)

Parameter	Unit	Description
Final Torque	Nm	Peak torque with target and min/max limits
Final Angle	°	Rotation angle from snug torque to final torque, with limits
Final Insertion Depth	mm	Measured insertion depth with target and limits

Each entry carries measuredValue, targetValue, lowLimit, highLimit, resultEvaluation, physicalQuantity, and engineeringUnits.

Process Curve (Trace Data)

Full time-series data is included in every result for detailed process analysis.

Channel	Unit	Description
tool_torque	Nm	Torque measured at the tool
tool_angle	°	Cumulative rotation angle
tool_speed	RPM	Rotational speed
driving_force	N	Linear force applied by the robot
driving_speed	mm/s	Linear insertion speed
insertion_depth	mm	Current insertion depth

Traceability — Associated Entities

Every result embeds an associatedEntities array that links the result to the physical assets and contextual identifiers that were present during the operation.

Always-present entities, populated automatically:

Entity	entityType	Description
Tool ID	1 (TighteningUnit)	Identifies which tool performed the operation
Program	27 (JoiningProcess)	The program or recipe that was executed

External entities are populated by the robot program. Any additional identifiers relevant to the application can be attached — for example a product serial number, a joint location, a batch number, or a work order. These are provided by the UR robot program and the schema imposes no constraints on what is included.

Note

Attaching external identifiers is a URCap feature. See Adding Traceability.

EntityDataType Fields

Field	Type	Required	Description
entityId	String	Yes	Unique identifier (serial number URI, UUID, or application key)
entityType	Int16	Yes	Type code per IJT Table 226. Common: 1 = TighteningUnit, 27 = JoiningProcess
name	String	No	Human-readable label (e.g., “tool”, “program”, “VIN”)
description	String	No	Additional free-text information
entityOriginId	String	No	Identifier of the system that assigned entityId
isExternal	Boolean	No	true if the ID was provided by an external system (MES, robot program)

Example Payload

[
  {
    "name": "tool",
    "description": "SN-10042",
    "entityId": "spin-robotics.com/SN-10042",
    "entityOriginId": null,
    "isExternal": false,
    "entityType": 1
  },
  {
    "name": "program",
    "description": "M5 Screw Standard",
    "entityId": "a3f7c2d1-4b8e-4f3a-9c1d-2e5b7a0f4c6e",
    "entityOriginId": null,
    "isExternal": false,
    "entityType": 27
  },
  {
    "name": "serial number",
    "description": "Body panel assembly — station 3",
    "entityId": "BP-2024-00471",
    "entityOriginId": "MES-LINE-3",
    "isExternal": true,
    "entityType": 21
  },
  {
    "name": "joint id",
    "description": "Front-left door hinge, upper bolt",
    "entityId": "JOINT-FL-HINGE-TOP",
    "entityOriginId": null,
    "isExternal": true,
    "entityType": 10
  }
]

Because all entities are embedded directly in the result event, a consumer receives everything needed to file the result into a traceability or MES system immediately — no secondary lookups required.

Namespace Reference

Index	URI	Purpose
0	OPC UA core	Built-in OPC UA types
1	http://spin-robotics.com/TighteningSystem/	Spin custom address space
2	OPC UA DI	Device Integration base types
4	OPC UA Machinery	Machinery base types
5	OPC UA Machinery/Result	Result management types
6	OPC UA AMB	Asset Management Base
7	OPC UA IJT/Base	Joining Technologies base types
8	OPC UA IJT/Tightening	Tightening-specific extensions