Ubisense UWB Sensors

Ubisense UWB Sensors are precision ultra‐wideband (UWB) measurement devices, which contain an array of antennas and ultra‐wideband radio receivers. The sensors detect UWB pulses from Ubisense tags, enabling the DIMENSION4 Real-time Location System to find the position of each tag in real time.

Each UWB Sensor belongs to one or more sensor groups. A sensor group contains a number of sensors that work together to identify the location of objects in a particular area. UWB Sensors operate within an Ethernet environment, by using standard network infrastructure. You can administer sensors remotely over the Ethernet network.

The UWB sensor infrastructure, including sensor groups and sensor properties, is configured by using the Location System Config tool from a client machine connected to the network. For more information, see Configuring DIMENSION4 and the DIMENSION4 Location System Config Online Help.

Ubisense supplies the following types of UWB Sensor:

• Directional sensors ("UWB Sensors")

• Omni-directional sensors ("Omni Sensors")

Sensors equipped to support GPS only, 2.4 GHz Detector Sensors, are also available.

Features of sensors and procedures for mounting them are described in the following sections.

About Ubisense UWB Sensors

A Ubisense UWB Sensor is a base station used by the DIMENSION4 Real-time Location System to find the location of objects in real-time. The sensor detects ultra-wideband (UWB) pulses sent by Ubisense tags and then finds the 3D position of the tag.

When compared to other wireless technologies, UWB technology is less affected by multipath interference. UWB Sensors can therefore detect the position of tags more accurately.

You can use UWB Sensors in different types of environments including manufacturing, healthcare, and workplace productivity.

Features on the Front Panel

The features on the front panel of a UWB Sensor, are shown in the following figure.

Front Panel of a UWB Directional Sensor

Feature	Description
Network Status LEDs	The three LEDs show the network status and indicate that the sensor is receiving and transmitting network signals. Top LED (Red). If this LED is on, the Ethernet link has been established. Middle LED (Green). If this LED is on, there is an activity on the Ethernet link. Bottom LED (Yellow). This LED shows the speed of the Ethernet link. If the LED is off, the speed is 10 Mbps. If the LED is on, the speed is 100 Mbps.
Sensor Status LED	Shows the status of the sensor. For more information about LED statuses, see DIMENSION 4 boot process overview
Fiducial Mark	Indicates the center of the sensor when recording the actual position of the mounted sensor using a Total Station.

Directional Sensors with High-Gain Antennas

The figure below shows the labels used to identify a directional sensor with a high-gain sensor.

Directional Sensors with External Antennas

The following figure shows the position of the hole to access the SMA Jack for attaching an external antenna.

Features on the Back Panel

The features on the back panel of a UWB Sensor, are shown in the following figure.

Back Panel of a UWB Sensor

Feature	Description
Back Cover Lock	Lock to attach the cover of the back panel.
Bracket Securing Points	Securing points to attach the sensor to a mounting bracket.
Ports 1-4 (Timing Output Only)	Ports for distributing timing signals to one or more sensors.
Port 5 (Timing Input/Output)	Port to either receive or distribute timing signals. The clock icon indicates that the port is used for timing input and output.
Power Over Ethernet (PoE) / Timing Input	The PoE port can be used in the following ways: For Ethernet only, if the sensor is either a timing source, or receiving timing input from another source. For combined Ethernet and Timing input, if the sensor is receiving timing from another sensor over the Ethernet cable. For combined Ethernet and Timing output, if the sensor is configured to send timing to another sensor over the Ethernet cable. For more information about setting up the network and timing cables, see Connecting Network and Timing Cables to Sensors.
Safety Plate Securing Point	Securing point to attach a safety plate to the sensor. Use the safety plate to fix a safety cable, as described in Attaching a Safety Cable to a Sensor.
Spirit Level	Indicates the roll of the sensor. For more information, see Setting the Roll of the Sensor to Zero Degrees.
Access to Reset Button	This hole provides access to the network reset button. For more information, see Returning Sensors to their Default Network Settings .
Timing Status LED	Indicates the current timing configuration of the sensor. The various statuses are: LED is off: The sensor is configured as the timing source. LED is Red: The sensor is configured as a Timing Sink to receive timing signals through Ethernet (PoE port). LED is Green: The sensor is configured as Timing Sink to receive timing signals through the Timing Port (Port 5). The LED does not indicate the timing status. For example, the LED might indicate that the sensor is configured to receive timing signals through a Timing Port. However, the sensor might not be receiving any timing signals. The clock icon indicates that the LED shows the timing configuration of the sensor.
USB Port	Port intended for future use.

Sensor Mounting Bracket

The UWB Sensor is shipped with a sensor mounting bracket that you can use for:

• Fixing the sensor to different types of surface such as walls, ceilings, or strut channels.
• Positioning the sensor correctly.

This section describes the features of the mounting bracket, fixing mechanisms for the wall plate and also how to use the Multi-tool.

Sensor Mounting Bracket Features

The features of the sensor mounting bracket are shown in the following figure.

Sensor Mounting Bracket Features

Feature	Used for...
Captive Bolt Holders with M5 Screws	Fixing the bracket to the back panel of the sensor.
Locking Knob	Connecting the support stems and fixing the sensor position at the appropriate angle.
Roll Adjuster	Setting the roll of the sensor to zero degrees (zero roll). Use the roll adjuster in conjunction with the: Spirit level, to check that the roll of the sensor is set to zero degrees. Wing nuts, for the final tightening of the roll adjustment, so that the position of the sensor is maintained at zero roll. For more information, see Setting the Roll of the Sensor to Zero Degrees.
Screw Holes	Fixing the wall plate to a surface.
Security Plate	Fixing the safety cable to the sensor.
Sensor Bracket	Fixing the bracket to the back panel of the sensor.
Spirit Level	Setting the roll of the sensor to zero degrees, which involves confirming that the sensor is not tilted or bent to one side or the other. Use the spirit level in conjunction with the roll adjuster. For more information, see Setting the Roll of the Sensor to Zero Degrees.
Support Stems	Supporting the sensor and positioning it at the correct pitch and yaw. The support stems are attached together with the locking knob. You can move and rotate the support stem to set the appropriate pitch and yaw for the sensor. For more information, see: Alignment and Angle of Support Stems Setting the Pitch and Yaw of the Sensor.
Variable Positioning Holes	Fixing the wall plate to a surface by using different types of fixing mechanisms such as U-bolts and pan-head screws. For more information, see Determining How to Fix the Mounting Bracket.
Wall Plate	Fixing the bracket to the required surface, such as a wall or a strut channel. For further information, see: Wall Plate Dimensions. Wall Plate Fixing Mechanisms.
Wing Nuts	Attaching the support stems firmly to the bracket holding the sensor and the wall plate. The wing nuts have an anti-rotation feature to ensure that the bracket/sensor assembly remains stable, for example if there is vibration or disturbance in the environment where you mount the sensor.

Alignment and Angle of Support Stems

By default, the support stem connected to the sensor bracket is aligned at an offset of -3 degrees, as shown in the following figure.

Alignment of Support Stems in Standard Mode

You can move the support stem downwards to set the approximate angles shown in the following figure.

Angles Possible in Standard Mode

When you completely rotate the support stems so that they are upside down (Rotational mode), they are aligned at an offset of 4 degrees, as shown in the following figure.

Alignment of Support Stems in Rotational Mode

In Rotational mode, you can move the support stem downwards, to set the following approximate angles:

• -10 degrees

• -24 degrees

• -38 degrees

• -52 degrees

The position of the sensor changes depending on the angle that you set, as shown in the following figure.

Angles Possible in the Rotational Mode

Wall Plate Dimensions

The wall plate of the mounting bracket is used for fixing the bracket to the required surface, such as a wall or a strut channel. This section provides dimensions of various fixing points on the wall plate.

Corner Holes

Dimensions of Corner Holes

Side Slots

Dimensions of Side Slots

 

Center Slots

Dimensions of Center Slots

Strap Slots

Dimensions of Strap Slots

Wall Plate Fixing Mechanisms

The fixing mechanism, such as screws or U-bolt, which you use to fix the bracket to the surface depends on the type of surface or object to which the sensor must be fixed. The fixing points on the wall plate are shown in the following figure.

Fixing Points on the Wall Plate

Variable positioning holes include side slots, center slots, and strap slots.

To Fix the Bracket by Using...	You Require...
Screw holes on the corners of the wall plate.	4 x M5 screws. 12 mm (outside diameter) washers.
Screws on the variable positioning slots on the wall plate.	Ideally, 4 screws. Large diameter washers and lock washers.
U-bolt through the variable positioning slots on the wall plate.	Plain washers and Nyloc nuts, or any other lock/nut mechanism.

Wall Plate Drilling Template and Jig

A stainless steel template of the wall plate is available from Ubisense. You can use this to mark the positioning holes, and also when drilling the positioning holes.

To use the template to mark the positioning holes

Align the cross-hairs in the template with the required center position, then mark the holes:

Using the Template to Mark the Position of the Fixing Points

To use the template as a drilling jig

Fix the template using a good quality masking tape and then drill the holes:

Using the Template as a Drilling Jig

Multi-tool for Securing the Mounting Bracket

A Multi-tool is available for use when securing the mounting bracket and sensor assembly in its final position.

Features of the Multi-tool

Safety Cable

The mounting bracket provides primary support for a sensor. However, if you are mounting a sensor at a considerable height, before attaching the sensor to the mounting bracket, we strongly recommend that you also attach a Sensor Safety Cable to fix the sensor to either a strong surface, or a fixture such as a beam. By using safety cables, you can ensure that the sensors do not fall down if, for example, the Wiring Contractor drops the sensor accidentally when mounting it.

We recommend that you use the Sensor Safety Cable (Part Code: UBIEAZYSFTY) supplied by Ubisense, to protect sensors (see Using Safety Cables to Protect Sensors for further guidance).

The features of the safety cable are shown in the following figure.

Features of the Safety Cable

Feature	Use for...
Clip	Attaching the safety cable to a strong surface or fixture.
Loop	Attaching the safety cable to the sensor.

The cable is supplied with the following components:

• A safety plate.
• A ¼” UNC bolt.

Mounting Sensors

You can mount sensors to different types of surfaces such as walls, ceilings, beams, and cable ducts.

Mounting a sensor involves the following tasks:

1. Attaching a Sensor Safety Cable to a sensor to protect it during and after the mounting process.
2. Mounting or fixing the sensor by using a mounting bracket.

Roles Involved in Mounting Sensors

The roles and responsibilities of the personnel who are involved in mounting sensors, are listed in the following table.

Role	Tasks
Field Engineers	Creating a detailed sensor and cable installation plan. Labeling and preparing sensors for mounting. Training and assisting Wiring Contractors, who mount the sensors.
Wiring Contractors	Mounting sensors by following the specifications in the sensor and cable installation plan. Meeting the local health and safety regulations. Connecting and testing network cables.

Prerequisites

Before you mount a sensor, ensure that:

• You have created a sensor installation plan that identifies the locations where each sensor must be installed.
• You have the required installation material and fixings for mounting the bracket. The fixings that you require for installing the bracket depend on the type of surface to which the bracket must be attached. For more information, see Determining How to Fix the Mounting Bracket.

To identify the sensor during installation, we also recommend that you attach an identification label to the front panel of the sensor.

For a checklist that lists the order in which you must complete the installation tasks, see the Sensor Mounting Checklist.

Process for Mounting a Sensor

The process for fixing a sensor at the mounting location is shown in the following figure.

Process for Mounting a Sensor

 

Using Safety Cables to Protect Sensors

A safety cable is intended to provide extra security, in addition to the support that the mounting bracket provides to the sensor. The safety cable protects the sensor from falling to the floor, for example, if the sensor or bracket is impacted, or if the sensor is dropped accidentally,

Identifying Suitable Locations to Fix Safety Cables

Before you fix a safety cable to secure a sensor, identify suitable fixing points or fixtures to which the cable can be attached. Ensure that the fixing point or fixture is strong enough to hold the sensor and is independent of the bracket mounting. For example, do not attach the safety cable to the base of the bracket.

Attaching a Safety Cable to a Sensor

Before you attach a safety cable to a sensor, ensure that you have the following components, which are supplied with the safety cable:

• Safety plate.
• ¼” UNC bolt. This is the type of bolt that is used with a camera tripod.

Sensor Securing Point and Safety Plate

To protect a sensor by using a safety cable:

1. Using the ¼” UNC bolt, fix the safety plate to securing point on the back panel of the sensor, as shown in the following figure.

   

   Attaching Safety Plate to the Sensor
   

2. Insert the loop of the safety cable into the slot on the safety plate, as shown in the following figure.

   

   Attaching Safety Cable Loop to the Safety Plate

3. Insert the clip of the cable into its loop, and then pull it tight, as shown in the following figure.

   

   Attaching Safety Cable to the Sensor
   

4. Pass the clip-end of the safety cable around a fixing point (such as a hook), or a fixture (such as a beam), and then clip it back to the cable.

Determining How to Fix the Mounting Bracket

Before you begin, determine how to fix the bracket at the sensor mounting location. You can fix the sensor mounting bracket to a variety of surfaces such as walls, beams, and cable ducts. The following figure shows how you can attach the mounting bracket to a pole clamp and Unistrut® system.

Mounting Bracket Attached to Various Objects

For information about the dimensions of the fixing points on the wall plate and the fixing mechanisms that you can use, see:

• Wall Plate Dimensions.

• Wall Plate Fixing Mechanisms.

Setting the Pitch and Yaw of the Sensor

You can adjust the mounting bracket to set the pitch and yaw of the sensor:

• Pitch is the vertical angle of the sensor.

• Yaw is the horizontal angle of the sensor.

The pitch and yaw is shown in the following figure.

Example of Pitch and Yaw

The pitch and yaw for a sensor vary depending on the location tracking requirements for the installation site.

Examples Showing Pitch and Yaw

Examples of a sensor positioned at a pitch of -41 degrees and -55 degrees, are shown in the following figure.

Sensor Positioned at Different Pitch Angles

Examples of a sensor positioned at a yaw of 60 degrees and ‑40 degrees are shown in the following figure. In this figure, the front of the sensor faces North, away from you.

Sensor Positioned at Different Yaw angles

Adjusting the Bracket

There are several adjustment points on the mounting bracket, as shown in the following figure.

Adjustment points on the Sensor Mounting bracket

Before starting, familiarize yourself with the adjustment points on the mounting bracket:

1. Try rotating the support stem at the wall plate (A). This changes the yaw.

2. Try adjusting the angle of the support stem at the locking knob. This changes the pitch.

3. Try rotating the support stem at the sensor bracket (B). The spirit level on the sensor bracket should be approximately level. You can make fine adjustments to this later.

Fixing the Bracket at the Sensor Location

After you have prepared the bracket and set the required pitch, fix the bracket at the sensor mounting location by using a suitable fixing mechanism such as screws, or a U‑bolt.

The process for fixing the bracket depends on the surface to which you are attaching the bracket, and the fixing mechanism that you use. For more information, see Determining How to Fix the Mounting Bracket.

After you have fixed the bracket, to prevent the bracket from moving, tighten the fixings that connect the wall plate to the surface.

Fixing the Sensor to the Bracket

To fix the sensor to the bracket, you must tighten the two M5 x 25 Hex Head screws, which are supplied with the bracket.

To fix the sensor to the bracket:

1. On the sensor bracket, ensure that the two M5 Hex Head screws are firmly enclosed in their captive bolt holders, with their heads sub-flush; these are interference fits.

2. Place the back panel of the sensor against the sensor bracket. Check that the captive bolt holders are aligned with the securing points on the back panel of the sensor, as shown in the following figure.

   

   Bracket Aligned with the Securing Points on the Sensor
   

3. Attach the sensor to the bracket by tightening the captive bolt holders with your fingers.

4. Tighten the wing nut that connects the support stem to the sensor bracket with your fingers.

Securing the Bracket and Sensor Assembly using the Multi-tool

After you have fixed the bracket and mounted the sensor, you must ensure that the bracket and sensor assembly remains strong and resistant to disturbances such as movement and vibration in the surrounding environment.

1. To tighten the wing nuts that connect the support stems to the wall plate and the sensor:

   1. Using your fingers, check that the wing nuts are reasonably tight. You should be able to undo them without needing any tools.
   2. Using the Multi-tool as shown below, tighten the wing nuts by an additional two clicks.

   

   Using the Multi-tool to Secure a Wing Nut

   Do not over-tighten the wing nuts as this may make it difficult to undo the wing nuts later without damaging the bracket or sensor assembly.

2. Tighten the locking knob that connects the two support stems of the bracket:

   

   Using the Multi-tool to Secure the Locking Knob

3. Tighten the captive bolts that connect the bracket to the sensor:

   Always use the Multi-tool to tighten the captive bolts. Do not use any other tools for this purpose.

   1. Place the Multi-tool over the captive bolt and press down on the captive bolt.

   2. Tighten with the Multi-tool. When you reach the correct tightness, the tool jaws open and the Multi-tool rotates freely.

      

      Using the Multi-tool to Secure a Captive Bolt

Setting the Roll of the Sensor to Zero Degrees

Roll is the amount that the sensor is tilted or bent to one side or the other. Examples of incorrect and correct positioning of the sensor, where the roll is set to zero degrees, are shown in the following figure.

Correct Positioning of Sensor at Zero Roll

Ensure that you set the roll of the sensor to zero degrees by using either the:

• Spirit level on the sensor mounting bracket.

• Spirit level under the back panel of the sensor.

 

Spirit Level on the Mounting Bracket

The sensor mounting bracket has a spirit level, as shown in the following figure.

Spirit Level and Roll Adjuster on the Bracket

Spirit Level on the Sensor

Additionally, the UWB sensor has a spirit level under its back panel, as shown in the following figure.

Spirit Level on the Sensor

Reading the Spirit Level Indication

Each spirit level has two markers. The location of the bubble in the spirit level indicates the position of the sensor. The acceptable position of the sensor, as indicated by the bubble in the spirit level, is shown in the following figure.

Acceptable Indication on Spirit Level

Location of the Bubble	Indicates that...	Acceptable (Yes/No)
A. Centralized between the markers.	The sensor position is at zero degrees.	Yes
B. Between the markers.	The sensor position is within 1 degree of being level.	No
C. On or below one of the markers.	The sensor position is within 2 degrees of being level.	No
D. Outside the markers.	The sensor position is more than 3 degrees of being level.	No

Setting the Roll to Zero Degrees

To set the roll of the sensor to zero degrees:

1. Check the location of the bubble in the spirit level.
2. Adjust the position of the sensor by using the roll adjuster. 
3. When the position of the sensor is at zero degrees, retain this position by tightening the wing nut that connects the support stem to the sensor bracket, by using your fingers.
4. Recheck the location of the bubble in the spirit level. If there is any backlash, readjust the position of the sensor.

Connecting Network and Timing Cables to Sensors

To locate the 3D position of a tag, UWB Sensors require the following connections:

• Timing: To record the precise time when the sensor detects a UWB pulse from a tag.
• Network: To receive and transmit information to the DIMENSION4 Real-time Location System.

Depending on your installation requirements, you can either:

• Supply combined network and timing to the sensors, by using a UbisenseTiming Distribution Unit (TDU). See Ubisense Timing Distribution Unit for information on connecting TDUs.

• Connect separate network and timing cables to the sensors.

Timing Sources and Timing Trees

You can configure any sensor to work as a timing source. The timing source is at the root of a timing cable tree, and provides synchronization signals to all the downstream or recipient sensors in that tree, as shown in the following figure.

Example of a Timing Tree

When you physically connect two sensors together with a timing cable, the upstream (supplying) sensor controls the timing signal and transmits its MAC address to the downstream (receiving) sensor. The sensors therefore detect the topology of the timing tree automatically.

In a D4 RTLS, multiple timing trees can exist in the same group, as shown in the following figure.

Multiple Timing Trees in the Same Group

Sensors use the Time-difference of Arrival (TDOA) and the Angle of Arrival (AOA) to identify the position of a tag.

The TDOA is only generated between sensors that have synchronized timing. When the D4 RTLS gathers the timing information from two sensors, it first checks if the sensors are synchronized, and then constructs a TDOA. However, all sensors from the group can use the AOA to find the position of the tag.

Guidelines for Setting up Timing

Sensors from a group work together to identify the location of objects and must be connected with timing cables so that they are synchronized.

Sensors from different groups do not share data and therefore do not have to be synchronized.

• Do not connect timing cables between two sensors that are not in the same group.
• Do not set up more than ten hops in a timing cable daisy chain.
• Do not connect timing cables across separate bands of sensors to synchronize disjoint groups.
• Do not create excessive daisy-chaining out of any individual sensor.

Supported Cable Types and Possible Range

UWB Sensors support Unshielded Twisted Pair (UTP) cables for timing and network. Cables must be Cat5e or above. The timing cables are physically the same as unshielded Ethernet cables, and use the same wire and connectors.

Unshielded Twisted Pair Cables are available with either 24AWG or 26AWG conductors. The range that you can cover with these cables, is summarized in the following table.

Cable Used For...	Possible Range
Timing only	Either: 250 meters with 24AWG conductors. 125 meters with 26AWG conductors.
Combined timing and network	The length is restricted to 100 meters by the Ethernet standard.

Connecting Separate Network and Timing Cables

Where a TDU is not wanted or required, the sensor, which is not the root timing source, receives:

• Network from a PoE network switch, which is also connected to the Location Platform server.
• Timing from another sensor.

You must therefore connect separate network and timing cables to each sensor.

Connecting Separate Network Cables

If you use separate network cables for sensors, you must connect each sensor by standard 100BASE‑TX Ethernet to a PoE switch, which is also connected to the Location Platform server.

PoE is the only method of supplying power to a sensor. If PoE switches are not available, you can use PoE injectors to supply power to sensors locally from AC mains.

Separate Network Cabling for a Group of Sensors and the Location Platform Server through a PoE Switch

Connecting Separate Timing Cables

If you are not using a TDU, sensors can receive timing either from the timing source or from another sensor that is connected to the timing source. The timing cabling for a group of three sensors is shown in the following figure.

Separate Timing Cabling

The timing source can supply timing directly to a maximum of five sensors. If you want to supply timing to additional sensors, you can daisy-chain sensors to distribute timing from one or more sensors that are currently receiving timing.

Daisy-chaining Sensors

Daisy-chaining sensors involves distributing timing from a sensor to additional sensors, as shown in the following figure.

Daisy-chaining Sensors

To daisy chain sensors, connect a timing cable from the timing output port on the sensor that is currently receiving timing, to the timing input port on the sensor that requires timing input.

Fixing IP Covers to Sensors

This section explains how to fix an IP back cover to the back panel of the sensor. You must fit an IP cover if there are any IP requirements to ensure, for example, that the sensor casing and wiring are not exposed to dust and water.

Fixing the IP54 Cover to the Sensor

This section explains how to fix an IP54 back cover to the back panel of the sensor. The IP54 cover, after fixing to the sensor, is shown in the following figure.

DIMENSION4 Sensor Fitted with the IP54 Cover

To fit the IP54 cover:

1. Insert the cables through the opening in the IP54 cover.
2. Connect the cables to the sensor.
3. Position the cover on the sensor and rotate the lock to fix it.

Returning Sensors to their Default Network Settings

Sensors can become unusable if they were previously assigned a static IP address and then this configuration is no longer available to them. If this is the case, sensors with firmware version 1025 and above can be reset to use the default (DHCP) network settings. The reset button is on the rear of the sensor inside the enclosure and can be accessed via a hole in the rear casing by means of a paper-clip or other thin wire (see below).

To reset a sensor:

1. Power-cycle the sensor and immediately press the reset button.
2. Keep the reset button depressed for five seconds until the Sensor Status LED flashes red three times (taking a total time of about 15 seconds from power on).

Rear View of a UWB Sensor with Access to the Reset Button Highlighted