MobileMap: Laser Rangefinder Integration

Overview

Laser rangefinders are important cruising tools that can improve efficiency and accuracy when measuring tree heights and when determining if borderline trees are in a plot. They are increasingly important for calculating tree coordinates for measuring stem maps for lidar data validation.

MobileMap 4.4.15 and higher includes significant enhancements to the integration of laser rangefinders for tree data collection. Once configured properly, MobileMap can read tree height, distance, and azimuth directly from supported laser rangefinders.

MobileMap can also collect current GPS location at time of laser data capture and store it as an offset GPS coordinate point for later calculation of the target tree location. When using this functionality, it is recommended that a high quality, sub-meter GPS be connected to your MobileMap Android device to ensure that the tree location can be calculated accurately.

When a tree record is saved, if MobileMap finds offset coordinates, distance and azimuth and appropriate fields for storing tree coordinates, it will attempt to calculate and store the tree coordinates. If the Trees layer is a Point layer (rather than the typical non-spatial attribute table) it will also save the geometry for the record. These calculations do not happen when the

Some laser rangefinders (e.g., Haglof Vertex Laser Geo) can connect directly to a sub-meter GPS and calculate the target tree coordinates directly. When using these devices, MobileMap can receive and store the tree coordinates at the same time as the tree height information.

Note: maintaining the connection to a Bluetooth laser rangefinder prevents incremental backups of the database while in the Tree List. This means that if you have backups set to 20 trees, for example, and you collect the 21st tree on a plot, MobileMap will save the tree to the database, but will not run the scheduled incremental backup of the database. The backup will still run when the plot is closed, as MobileMap will close the Bluetooth connection at this time (and reopen it when the next plot is opened). If you are using a Bluetooth laser rangefinder and you are collecting a large number of trees per plot, you may want to close and reopen the tree list partway through the data collection to force MobileMap to make a database backup mid plot if you are concerned about not having frequent database backups.

Supported Devices

While most Bluetooth devices will pair with MobileMap android devices and communicate using the NMEA data specification, we have found that the exact messages sent vary by device manufacturer and model. The table below contains the laser rangefinders have been been integrated and tested to date. Similar devices by these manufacturers may work as well, but they have not yet been tested.

If you are a device manufacturer or vendor and would like to see your device listed here, please contact us. Similarly, if you are a MobileMap customer with a Bluetooth compatible device that is not listed here, we would like to hear from you to see if we can add support for your device.

Manufacturer

Model

Height

Distance

Azimuth

Offset X/Y*

Tree X/Y

Manufacturer

Model

Height

Distance

Azimuth

Offset X/Y*

Tree X/Y

LaserTech (LTI)

TruPulse 200

X

X

 

X

 

LaserTech (LTI)

TruPulse 360R

X

X

X

X

 

Haglof

Vertex Laser Geo

X

X

X

X

X

*Offset X/Y is captured from the MobileMap Android device via the onboard GPS antennae or a Bluetooth connected GPS (e.g., Juniper Geode or EOS Arrow 100). It does not come from the laser rangefinder itself, but the capture is triggered when laser rangefinder data are received, so the coordinates stored are the GPS coordinates at the time of laser data capture. It is essential that the GPS antenna be co-located with the laser rangefinder (not at plot center!) for these data to be useful.

Pairing Laser Rangefinder to Android Device

Follow the steps below for your laser rangefinder make to enable Bluetooth and connect (pair) your laser rangefinder to your Android device.

LTI TruPulse

  1. Ensure that Bluetooth is enabled on your laser rangefinder

    1. LTI TruPulse steps (from TruPulse 200 user manual)

 

Haglof Vertex Laser Geo

  1. Press ON button to turn laser on

  2. Use DMS or SEND button to cycle through main options until you see SETTINGS, then press ON button to select

  3. Use DMS or SEND button to highlight BLUETOOTH, then press ON button to select

  4. Use DMS or SEND button to check the USE BLUETOOTH checkbox, then press ON button to return to main menu. The Bluetooth icon should be visible to indicate that Bluetooth is on.

 

Pairing to Android Device

  1. Enable Bluetooth on your Android device using Android Settings

    1. Settings > Connections > Bluetooth

    2. Look for appropriate device name in the list of available Bluetooth devices

      1. TruPulse 200 might show up as ‘TP200B-107632’ where ‘TP200B’ stands for TruPulse 200 Bluetooth enabled. The numbers at the end may vary with version of your device.

      2. Haglof Vertex Laser Geo might show up as ‘VL_GEO_60020’ where ‘VL_GEO' stands for Vertex Laser Geo. The numbers at the end may vary with version of your device.

      3. If you do not recognize your device in the list of available Bluetooth devices but are confident that you have enabled Bluetooth functionality in the device, check your user manual for the device name that will be displayed

    3. Select your device from the list

      1. If asked if you want to pair select ‘Yes’, ‘OK’, or ‘Pair’

      2. If prompted for a PIN, follow instructions from your laser rangefinder user manual

        1. For LaserTech devices, the PIN is typically ‘1111’.

        2. For Haglof devices, the PIN is typically ‘1234’.

    4. Your device should now appear in the Paired Devices list

    5. Close Android settings

Configuring MobileMap

Follow these steps to configure MobileMap to use your laser rangefinder:

  1. Configure laser range finder tree-level settings found in Settings > MobileMap Cruise > Trees. Make sure to enter exact field names (not aliases) for all tree attribute fields that you intend to populate via the laser rangefinder. Available settings:

Setting

Purpose

Setting

Purpose

Tree Height 1 Field

Used to store incoming height data, in units selected on the laser rangefinder. Typically used to record total tree height, but if 2 heights are collected for each tree (e.g., merch height and total height) this should be set to the lower height to enable collection of tree from bottom to top.

Tree Height 2 Field

Same as above, but if 2 heights are collected for each tree (e.g., merch height and total height) this should be set to the higher height to enable collection of tree from bottom to top.

Tree Distance Field

Can be used to store incoming distance data, in units selected on the laser rangefinder. Typically used to record the distance of a tree from plot center or from a GPS measurement.

Tree Azimuth Field

Can be used to store incoming azimuth data, in degrees. Typically used to record the azimuth of a tree from plot center or from a GPS measurement.

Tree Longitude Field

Can be used to store the Latitude value for the target tree. Only possible when laser rangefinder includes an integrated or connected GPS and supports onboard calculation of target tree coordinates based on GPS location, distance and azimuth.

Tree Latitude Field

Can be used to store the Latitude value for the target tree. Only possible when laser rangefinder includes an integrated or connected GPS and supports onboard calculation of target tree coordinates based on GPS location, distance and azimuth.

Tree Offset Longitude Field

Can be used to store the Longitude value from the MobileMap device at time of laser rangefinder data capture. Typically used with Bluetooth sub-meter GPS connected directly to the MobileMap device. Used in post-processing to calculate the coordinates of the target tree.

Tree Offset Latitude Field

Can be used to store the Latitude value from the MobileMap device at time of laser rangefinder data capture. Typically used with Bluetooth sub-meter GPS connected directly to the MobileMap device. Used in post-processing to calculate the coordinates of the target tree.

  1. Configure MobileMap’s Bluetooth connected devices

    1. Actions > Bluetooth Devices

    2. Find the correct Bluetooth device from the list of paired devices

    3. Select the appropriate device type (Rangefinder LTI or Rangefinder Haglof)

    4. Slide the toggle to enable this device

    5. You should see a message saying that the device has been connected and a green checkbox by the device

    6. Tap Save (disk icon) to close this dialog and save the settings

Collecting Laser Rangefinder Data

To collect tree heights and other data (e.g., distance, azimuth, GPS coordinates) with a laser rangefinder, begin by following the standard cruise workflow to edit a plot and open the tree list. When MobileMap is configured using the steps above, attribute fields that can be populated directly from the connected laser rangefinder will have their column headings highlighted in cyan. In the example below, a LaserTech TruPulse 360R is configured to populate the total height (alias: Ht), distance to tree (alias: Dist) and azimuth (alias: Az) to tree fields. MobileMap is also configured to populate the GPS location at time of laser rangefinder data capture into GPS offset latitude and longitude fields (these fields are currently hidden from the tree list in the image below, but are configured in settings to receive the offset latitude and longitude).

If you do not see the cyan highlights either a) the fields settings have not been properly configured in settings (Settings > MobileMap Cruise > Trees), or b) the laser range finder has not been properly paired, configured or connected. If collection was previously working, then the problem is likely the Bluetooth connection (rather than configuration). The easiest way to resolve this is typically to verify that the laser rangefinder is on (has not 'gone to sleep') then close and re-open the tree list. If you find that this happens repeatedly during data collection, contact our support team.

When a measurement is taken with the laser rangefinder, it may be immediately sent to MobileMap (LTI) or may need to be manually sent via the ‘Send’ button (Haglof). MobileMap will be listening for the transmission and once it is sent, MobileMap will populate the relevant attribute fields automatically and play an audio alert to notify you that the data were received. For some devices (e.g., LTI) you may hear multiple alerts as individual measurements are sent in batches (e.g., first the horizontal distance and azimuth, then the tree height).

LaserTech TruPulse 200

When using an TruPulse 200 and recording tree heights, use Height (HT) mode.

  1. Start by pointing at the tree and holding the ‘Fire’ button until the distance is displayed. Release the button.

  2. Next, aim for the base of the tree and hold the ‘Fire’ button until the angle is displayed and steady. Release the button.

  3. Next, aim for the desired height (e.g., merch height or tip of tree) and hold the ‘Fire’ button until the angle is displayed and steady. Release the ‘Fire’ button. The TruPulse will display the height in the viewfinder and send the result to MobileMap. Verify the value is correct and in the correct row and cell.

  4. If the distance to tree is also desired, use the down arrow on the TruPulse 200 to select Horizontal Distance (HD) mode. Once in HD mode, start by pointing at the tree and holding the ‘Fire’ button until the distance is displayed. When you release the ‘Fire’ button, the TruPulse will display the horizontal distance to the tree in the viewfinder and send the result to MobileMap. Verify the value is correct and in the correct row and cell.

LaserTech TruPulse 360R

When using the TruPulse 360R the height, distance and azimuth can all be captured in height (HT) mode.

  1. Start by pointing at the tree and holding the ‘Fire’ button until the distance is displayed. When the ‘Fire’ button is released, it will be sent to MobileMap. An alert will sound and the distance and azimuth will be populated. GPS offset coordinates will also be captured from the best available GPS location and displayed in the appropriate cells.

  2. Next, then aim for the base of the tree and hold the ‘Fire’ button until the angle is displayed and steady. When the button is released, an alert will sound but no new data will be populated.

  3. Next, aim for the desired height (e.g., merch height or tip of tree) and hold the ‘Fire’ button until the angle is displayed and steady. When you release the ‘Fire’ button, the TruPulse will display the height in the viewfinder and send the result to MobileMap. Verify the value is correct and in the correct row and cell.

Haglof Vertex Laser Geo

When using the Haglof Vertex Laser Geo, collect data using 3-point height (HEIGHT 3P) mode. Use the DME and SEND buttons to cycle through the modes until HEIGHT 3P is displayed on the heads-up display.

 

  1. Press the on button to select HEIGHT 3P mode and begin data collection

  2. When the red dot sight is turned on (when viewing through viewfinder) and the display reads AIM AND PRESS ON TO FIRE LASER, aim at an optional point on the target tree and give a short press at ON to measure the distance and angle to the tree. Continue to aim at that point on the tree until a short beep goes off and a result is shown in the heads-up display.

    1. A temporary height result, to the point you are aiming at from ground, including the preset eye
      height, is shown, but this should be ignored.

    2. If you have missed the target, you can start over by aiming at the point, and give a quick/short press at ON.

    3. If needed, use the DME button to temporarily change the preset Laser mode (First-, Strongest-, Last- target) to allow the laser to work in optimal mode for the current measuring situation. For example, use Last-target to avoid having the laser reflect on objects in front of your target object, such as grass or bushes.

  3. Aim at the base of the tree. Press ON and keep pressing until a beep goes off and the aiming dot is turned off. Release the ON button.

  4. Aim at the top (or other height) on the tree. Press ON and and keep pressing ON until a beep goes off and a result is shown in the heads-up display. Release the ON button.

  5. The heads-up display will now show the results including:

    1. SD Slope Distance (m or feet)

    2. HD Horizontal Distance (m or feet) - This can be stored in MobileMap when a distance and offset is needed for stem mapping. It can also be used in conjunction with the limiting distance tool in MobileMap to determine if a borderline tree is in.

    3. DEG Angle (Degrees, % or Gradians) - This can be stored in MobileMap when a distance and offset is needed for stem mapping.

    4. H1 Height (m or feet) - This is the most commonly used data from laser rangefinders and can be total height or merch height, depending on the cruise spec.

  6. Press the Send button to send all measurements to MobileMap. You should hear the alert and see all fields (height, distance, azimuth, offset latitude, offset longitude) populate with the collected values. During initial testing, we recommend that these numbers are compared to the values displayed on the Haglof heads-up display to ensure that the measurements have been mapped to the correct fields in the tree list.

Troubleshooting

As described above, if you open the tree list and you do not see the cyan highlights for attribute fields that will be populated by the laser range finder then either a) the fields settings have not been properly configured in Settings > MobileMap Cruise > Trees, or b) the laser range finder has not been properly paired, configured or is not on.

If you previously had MobileMap working with your laser rangefinder, but you open the tree list and do not see the cyan highlights, it might mean that the laser rangefinder was not available (asleep, out of range, connected to another device) when the tree list was opened. In this case, try closing the tree list, verify that the laser rangefinder is active, then re-open the tree list. If that doesn’t work, try closing the tree list, then the plot, then open the Bluetooth Devices interface (Actions > Bluetooth Devices). Verify that the device is listed and that the correct device type is selected and that it is enabled. If you see the green checkmark, you should be ready to re-try tree data collection.

If you do not hear the audio alerts but you do see laser rangefinder data being read and stored in the tree list, check your device audio settings and adjust the notification volume.

If you are still unable to correctly configure your device and collect laser rangefinder data, please contact our support team.