2 | System Overview An overview of the COMMAND hardware and harnessing system 2.1 | System Architecture Theory of Operation COMMAND is an electronic control system designed by T3RRA consisting of an Electronic Control Unit (ECU) along with a harnessing system to interface with different sensors, hydraulic and tractor systems.  Once installed and configured, the ECU acts as both a control system and interface. It will communicate with a PC running T3RRA software, the earthmoving implement and sensors providing real-time feedback on the position of the implement, and tractor diagnostic data where available.  Level COMMAND can then control the implement based on your current position and design elevation, while satisfying constraints e.g. cut depth limits.  Manual Control Mode In Manual Control Mode, and also when the system arming switch is deactivated, COMMAND is Disengaged and any prescribed elevations sent to the ECU will not result in activation of hydraulics. Hydraulic outputs can still be activated using a connected joystick or tractor SCV levers. These will function regardless of whether  COMMAND Automatic Control is Disengaged or Engaged . Automatic Control Mode Once the operator has Armed the system and Engaged Automatic Control Mode, the ECU activates hydraulic outputs based on: Prescribed elevation Current elevation Calibration parameters Tracking sensitivity Tracking/acquire thresholds While Engaged , joystick movement can override automatic control. Depending on configuration, joystick movement can either Disengage Automatic Control Mode or Momentarily Disengage control until the joystick returns to centre. 2.2 | Supported Implement Types COMMAND machine profiles are used to store all configuration settings for that particular implement including GNSS input selections, valve configuration, calibration and tuning values etc. Implemented and Tested Machine Profiles COMMAND  currently has the following machine profiles available for selection on the ECU: Machine Profile Controlled Functions Example Usage Single Scraper - Height Function 1 - Height A bucket scraper with single proportional height control valve and a single GNSS receiver Single Scraper - Height & XSlope Function 1 - Height Function 2 - XSlope / Tilt A bucket scraper with a single proportional height and single proportional tilt control valve fitted with a single GNSS receiver and single inertial measurement unit (IMU) Single Ditcher - Height Function 1 - Height A V-ditcher with a single proportional height control valve and a single GNSS receiver. Machine Profiles Currently In Testing Machine profiles listed below are currently under development and may become available in future software releases. Machine Profile Controlled Functions Example Usage Single Ditcher - Height & Pitch Function 1 - Height Function 2 - Pitch A tile plow with a single proportional height, single proportional pitch control valve, single GNSS receiver and single inertial measurement unit (IMU).   Tandem Scrapers - Height Function 1 - Height 1 Function 2 - Height 2   Two bucket scrapers in tandem, each with a single proportional height control valve and single GNSS receiver. Single Scraper - Dual Height Function 1 - Height A bucket scraper with a single proportional height control valve but two GNSS receivers (One on the  left of the implement, one on the right) Single Scraper - Height (Dual Cylinder) Function 1 - Height Left Function 2 - Height Right A bucket scraper with dual proportional height control valves (controlling left and right height separately), and two GNSS receivers (left and right). Maintains blade angle to allow manual X-Slope / Tilt operation. Single Scraper - Height & XSlope (Dual Cylinder) Function 1 - Height Left Function 2 - Height Right A bucket scraper with dual proportional height control valves (controlling left and right height separately), and two GNSS receivers (left and right).  2.3 | GNSS Receiver & IMU Compatibility The requirements below outline the important components and considerations for using a GNSS receiver with  Level COMMAND . StarFire RTK, NMEA 0183 Fixed RTK over RS232 serial, or NMEA 2000 Fixed RTK output over ISOBUS/CANBUS. Suitable adapters are available to connect RS232 or CANBUS and 12V external power to the  COMMAND harnessing system.   Ruggedised and suitable for earthmoving machine control applications. Receivers being used with COMMAND  must be capable of RTK positioning calculations. Differential GNSS or SF corrected signals e.g. SF3 are NOT considered suitable for implement position feedback as position accuracy and repeatability are insufficient. John Deere StarFire TM COMMAND  is able to interface with all modern StarFire receivers over ISOBUS/CANBUS for position feedback, including StarFire 3000, 6000, 7000 & 7500 models. NMEA 2000 (CANBUS) COMMAND  is able to interface with GNSS receivers supporting NMEA 2000 standard output over ISOBUS/CANBUS for position feedback including but not limited to Case Vector Pro, New Holland PLM Cygnus & Trimble NAV 900 receivers. Supported NMEA 2000 PGNs 129029 - GNSS Position Data 129539 - GNSS DOPs 129025 - Position, Rapid Update 129026  - COG & SOG, Rapid Update 129028 - Altitude Delta, Rapid Update Position Update Rate  A minimum position update rate of 5 Hz is required.  10 Hz is recommended. NMEA 0183 (RS23 2 Serial) COMMAND  is able to interface with any receiver capable of providing NMEA 0183 standard sentences over RS232 serial for position feedback. The sentences below are required at a minimum for usage with Level COMMAND . Required Sentences GGA -  Time, position, and fix related data GSA -  GNSS DOP and active satellites VTG - Actual track made good and speed over ground Optional Sentences RMC - Position, Velocity, and Time ZDA - UTC day, month, and year, and local time zone offset Position Update Rate  A minimum message rate of 5 Hz is required. 10 Hz is recommended. RS232 Baud Rate The RS232 baud rate can be selected in Level COMMAND as 19200, 38400, 57600, and 115200 bps. A baud rate of 38400 is recommended. Compatible Cross-slope / Roll / Tilt Sensors For users making use of Cross-slope control using the COMMAND ECU's second output function, we recommend the use of the T3H-E003 COMMAND Inclination Sensor – TARS-B to ensure that the angle sensor being used is robust and accurate for automatic implement control. StarFire TM TCM (Terrain Compensation Module) COMMAND can make use of the in-built StarFire TCM, which provides feedback on pitch and roll angle of the receiver. The StarFire TCM can be selected as a Cross-slope / Tilt sensor but we cannot guarantee the accuracy / bias drift of the sensor and generally recommend the use of  T3H-E003 shown below. T3H-E003 - COMMAND Inclination Sensor A TARS-B inertial measurement unit configured by T3RRA can be used to provide reliable feedback on the pitch and roll angle of the implement and can be mounted on the scraper for automatic Cross-slope control when using receivers such as Case IH Vector Pro or Trimble NAV 900. 2.4 | Tractor / Electrohydraulic Compatibility COMMAND can make use of either in-built rear tractor electrohydraulic valves, commonly referred to as SCVs (Selectable Control Valves) or auxiliary remotes, or externally mounted electrohydraulic valves. For each valve type, COMMAND is able to provide two raise and lower functions for automatic control of function 1 (e.g. height) and function 2 (e.g. cross-slope / tilt). For CANBUS based valve types, any available SCVs/Remotes will be available for selection. For proportional solenoid, Analog Voltage (0-5V) and Danfoss PVE types, the number of selectable outputs is limited to the number of available physical outputs on the ECU suitable for analog voltage laser inputs or external EH valves. Valve Interface Description Suitable example tractors/valves JD CAN COMMAND can communicate directly with John Deere SCVs over CANBUS, sending flow requests that will be enacted by the John Deere tractor hydraulic system. Most modern John Deere tractors, e.g. 8R, 8RT, 9R, 9RT, 9RX. Proportional Solenoid COMMAND can provide closed-loop PWM signals suitable for controlling external proportional solenoid valves requiring maximum flow current of less than 2 Amps. Scraper systems using external proportional solenoid valves such as Eaton Vickers, Rexroth or Hydac. J1939 COMMAND can communicate directly with the T3RRA VM or other compatible hydraulic controllers using the J1939 messaging standard. Tractor/scraper systems requiring manual controls beyond what the COMMAND ECU is capable of providing. Fendt ONE COMMAND can communicate directly with Fendt SCVs over CANBUS, sending flow requests that will be enacted by the tractor hydraulic system. Fendt Gen 7 / ONE tractor models PWM to 0-5V Using the T3H-V001 legacy analog output adapter, COMMAND can provide 0-5V analog voltage signals suitable for John Deere legacy proportional SCV controller or Case 0-5V EHR controller inputs. John Deere legacy proportional laser inputs or Case 0-5V EHR inputs. Fendt SCR/S4/MT Using the Fendt SCV adapter, COMMAND  can communicate directly with Fendt SCVs over CANBUS, sending flow requests that will be enacted by the tractor hydraulic system. Fendt SCR, S4 and MT models where the SCV control bus is separated from the ISOBUS. Danfoss PVE Using the PVE Valve Adapter, COMMAND can provide 0-Vs ratiometric voltage signals suitable for controlling external Danfoss PVEM, PVEA, PVEH and PVES valves. Scraper systems using external closed-loop proportional valves such as Danfoss PVEM, PVEA, PVEH or PVES. 2.5 | Selecting System Components Correct component selection is important for reliable installation and operation of the COMMAND system. Harnessing requirements will vary depending on tractor model, implement configuration, GNSS receiver type, and hydraulic interface. For assistance selecting compatible components, use the COMMAND kit picker at t3rra.com or contact T3RRA. Factors that will affect harnessing requirements include: Tractor brand Tractor model Scraper brand Scraper model GNSS receiver model Available Electrohydraulic Valves John Deere Harnessing Compatibility The COMMAND harnessing system has been designed to allow us to leverage existing customer and dealer knowledge of John Deere harnessing systems. We can then take advantage of this familiarity on the technical support front, while leveraging the fact that John Deere dealers also possess many of these parts in stock at-the-ready. Typical John Deere Components SKU / Part No. Name BPF10403 OR BPF10404  OPTIONAL POWER Constant Power Harness (Row Crop) OR Constant Power Harness (Articulated) BPF11117 REQUIRED Front Extension Wiring Harness Kit (including terminator module) RE174725 OR  RE174726 IF NO ISOBUS PRESENT GreenStar™ Ready Field Installation Kit (Rowcrop) OR GreenStar™ ISO Implement Connector Field Installation Kit (Articulated) PF90538 IF USING STARFIRE GNSS Implement Receiver Wiring Harness Kit BPF10547 REQUIRED iGrade Counterbalance Valve kit -  generally recommended and mandatory for proper operation with certain SCVs and external valves. Base COMMAND Components The components below are required for a base COMMAND installation. SKU / Part No. Name T3H-E001 COMMAND ECU – Controller Only T3H-L001 COMMAND ECU Licence – Licence Only T3H-C002 COMMAND ECU Adapter - CAN & Analog T3H-C003 COMMAND Arm/Engage Switch Adapter T3H-C004 COMMAND Arm/Engage Switch T3H-C005 COMMAND ISOBUS/Ext Breakout Adapter  T3H-C006 COMMAND Cab Breakout Adapter T3H-C008 COMMAND Cab/Ext Extension Adapter T3H-T001 Tablet Serial Interface Adapter (RA 4m) Optional COMMAND Components Components listed below are optional for COMMAND and will only be required for certain tractor models, scraper models, GNSS receivers, Tilt sensors or Electrohydraulic valves. SKU / Part No. Name Tractor Harnessing   T3H-F001 Cab Convenience Power Adapter  T3H-F002 External Loose End Power Adapter T3H-F003 COMMAND Inline Fuse Adapter  T3H-M001 COMMAND J1939 Diagnostic Adapter (Green) T3H-V001 COMMAND Legacy Analog Output Adapter T3H-T002 Tablet Serial Interface Adapter (RA 6m) Implement Harnessing   T3H-E003 COMMAND Inclination Sensor – TARS-B T3H-G001 COMMAND NMEA Extension Harness (8m) T3H-G002 COMMAND Impl Adapter – NAV-900 / Ag372 T3H-G003 COMMAND Impl Adapter – Emlid Reach RS2/RS2+/RS3 T3H-G004 COMMAND Trimble NMEA Output Adapter T3H-G007 COMMAND NMEA Extension Harness (12m) T3H-S001 COMMAND Impl Adapter – Stub Junction T3H-S003 COMMAND Impl Adapter - TARS Extension