Leica MOJO RTK Administrator Guide

For more information:
www.mojoRTK.com
Page 1/5Document #1055 rev1.1
HOW TO GUIDE: RTK Fallback
This document describes the RTK Fallback feature, which can be enabled by
entering an unlock code.
Description
The mojoRTK system provides guidance for a tractor along, and parallel
to, a single straight line (the wayline)
Accurate guidance can only be guaranteed whilst the mojoRTK console
has a good GPS fix and is receiving reference corrections
RTK Fallback allows the operator to continue working for a period of time
after the loss of signal being received from the base station
The mojoRTK must be receiving GPS data for RTK Fallback to be enabled
Following the restoration of signals from the base station the mojoRTK
console will correct for offset if the offset error is less than the limit set
for Maximum Drift
RTK Fallback is a primarily a fall-back mechanism and accuracy to the line
will degrade over time
Benefits
Using RTK Fallback allows the mojoRTK to continue to guide the vehicle for
up to 10 minutes after the base station signal has been lost. The loss of
signal may be due to terrain, vegetation, or interference.
Availability
RTK Fallback is available from Service Pack 4. Existing customers will need to
purchase an unlock code to activate this feature. All systems sold as of 1
January 2009 will have this software enabled.
Limitations
RTK Fallback can not be initiated until a GPS fix has been obtained on both
the mojoRTK console and the base station.
RTK Fallback will cease to operate if the mojoRTK console loses GPS fix.

For more information:
www.mojoRTK.com
Page 2/5Document #1055 rev1.1
RTK Fallback, when activated, will initiate 30 seconds after a loss of signal
from the base station.
RTK Fallback operation is limited to a maximum of 10 minutes without
receiving corrections from the base station. The mojoRTK console must
receive at least 15 seconds of continuous reference corrections for the 10
minute interval to reset.
If the position drift upon signal restoration is greater than the Maximum
Drift set, guidance will be disabled and an error screen will be displayed on
the mojoRTK console.
Required Items
Updated ME3 firmware (v3.610 B4 or later) does need to be installed
via a USB stick for RTK Fallback to be enabled. Talk to your Value
Added Reseller or Leica Geosystems representative about how to obtain
the ME3 firmware.
Unlock code to unlock the RTK Fallback (SP4 and higher) feature on the
mojoRTK console. The unlock code will automatically be generated by
Leica Geosystems for consoles purchased after 1 January 2009. For
consoles purchased before 1 January 2009, an unlock code can be
purchased from Leica Geosystems.
Value Added Resellers can obtain the unlock code directly from Leica or
by logging onto www.mojoRTK.com and viewing the information for the
particular console which is uniquely identified by its serial number.
Service Pack 4 or later software.
ME3 upgrade procedure
(Once service pack 4 or later software has been installed the ME3)
With the console turned off insert a USB with the ME3 firmware into the
top USB port on the console.
Turn on the console
In the menu go to service -> upgrade gps and press ok
The console will start to install the ME3 upgrade, this process will take
around 5minutes
DO NOT TURN OFF THE CONSOLE DURING THE UPGRADE
Once the install is finished the screen should be green in colour with
“upgrade complete” on the screen
Turn off the console and remove the USB stick

For more information:
www.mojoRTK.com
Page 3/5Document #1055 rev1.1
mojoRTK Configuration
Installing the unlock codes manually on the mojoRTK console
Start the mojoRTK console
Press the OK button to enter the Menu
Using the Main Dial, select Settings -> Extended Features -> Enter New
Code
Enter the 16 digit code by using the Main Dial to select the value for a
digit and pressing OK or Escape to move backwards and forwards
between digits
Once all 16 characters are entered and checked press OK
After the code has been accepted the Console will restart
Installing the unlock codes using Virtual Wrench on the mojoRTK Console
1. Start the mojoRTK console
2. Press softkey 3 twice to bring up the Virtual Wrench connection screen
3. Select Yes using the Main Dial and press the OK button to connect to
Virtual Wrench
4. Once connected the new unlock codes will be automatically downloaded
and installed
5. A message will then appear stating which unlock codes have been
installed, press OK and the console will restart
RTK Fallback
Under RTK Fallback the vehicle may drift left or right. Over
time this drift may become significant. The default maximum
drift limit is 0.1m. The user has the option to set a maximum
drift value for RTK Fallback. Navigate to
Menu -> Settings -> Guidance -> Max. Drift. The maximum
allowable value is 10.00m.
With the RTK Fallback feature enabled, RTK Fallback will
automatically activate following the loss of signal from the
base station.
In a typical scenario the user would set up for the days work.
A GPS fix would be obtained by the mojoRTK console and the
base station. The user would then commence operating. The
base station icon would have at least one bar and the
satellite icon would have at least one bar.

For more information:
www.mojoRTK.com
Page 4/5Document #1055 rev1.1
If at some point the signal to the base station is lost, after 15
seconds the user is presented with the continue on RTK
Fallback screen.
Selecting No will disengage steering.
Selecting Yes will allow steering to remain engaged. The next
time RTK Fallback activates the confirmation screen will be
displayed.
Selecting Always will allow steering to remain engaged. RTK
Fallback will remain activated for a maximum of 10 minutes.
After the 10 minutes a RTK fix will be needed before RTK
Fallback can be used again. The next time RTK Fallback
activates the confirmation screen will not be displayed.
If Always has been selected the prompt to activate RTK Fallback will not be
shown unless the mojoRTK console has been restarted.
If Yes or Always has been selected then RTK Fallback will remain activated
for a maximum of 10 minutes. After the 10 minutes a RTK fix will be needed
before RTK Fallback can be used again. Be aware there will be some drift
and it may be necessary to make some corrections using Nudge Offset.
Note: If guidance is being performed using the John Deere Greenstar™1 or
2 then the nudge function cannot be performed on the mojoRTK console. It
must be performed on the Greenstar™.
Nudge Offset
Nudge Offset provides the operate a mechanism to correct the
drift that will occur while RTK Fallback is activated. To use the
Nudge Offset press the Esc key repeatedly until the main
screen is displayed. Press function 2 (the mojo button) and you
are presented with the Nudge Offset menu.
Either drive to the line and press Ok or tune the main dial left or right to
nudge the vehicle left or right 5cm per click.
Note: The Nudge Offset is a temporary offset and will not be kept after
corrections are re-acquired.

For more information:
www.mojoRTK.com
Page 5/5Document #1055 rev1.1
When the base station signal is re-acquired, the mojoRTK
console determines the error. If the error is outside of the
maximum drift the mojoRTK console will issue an audible
warning, turn off the steering and display a message on a red
background.
Press OK to acknowledge and clear the error, drive to within
the engage limits for the wayline and engage guidance.
Alternatively if the error is under the maximum drift limit the
mojoRTK console will snap back to the wayline.
Depending on the error there can be between 0.1 to 10.00
metre jump in the working line.
These jumps can be mitigated using the nudge functionality.