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Attach and Operate Implements#

This tutorial shows how to select an implement for the Maxxum and how to operate the hitch, the PTO and each of the eight implements. You do each task with the keyboard or with a drive script.

Before You Start#

Use a field for the implements that work the soil. On pavement and gravel, the tines feel no force. The examples start on field F39, which has no crop. These options set the start position on that field:

-VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

The Maxxum carries one implement in a session. The Polaris has no implements. The Implement Catalog describes each implement.

Select an Implement#

With an Option#

  1. Start a session with the option -Implement= and the identifier of the implement.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=chisel_plow \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The Maxxum is on the field with the chisel plow in the raised position. The log contains this line.

    ACRES_IMPLEMENT_READY id=chisel_plow keys=67 mass_kg=1100.0 com_m=(-1.347, 0.000, 1.066) width_m=2.70 depth_range_m=0.000-0.279 lever=0.235 roller_deg=2.00 hitch_mode=0 draft_setpoint_n=15000 pto_ratio=0.0000

    The HUD shows the card Chisel Plow with the badge Raised.

The identifiers are cultivator, chisel_plow, disc_harrow, seed_drill, mounted_sprayer, loader_bale_fork, backhoe_attachment, square_baler and none. The game stops with a message when the identifier is unknown.

With the Menu#

  1. Start the game without options.

    Packaged/Linux/Acres.sh

  2. Select New Simulation or Pilot.

  3. Open the tab Tractor.

  4. In the group Implement, set Implement.

  5. Set the other values of the group. The table below lists them.

  6. Select Start.

Menu Setting Applies To Range
Working Depth Cultivator, chisel plow, disc harrow 0 cm to 30 cm
Hitch Control The five mounted implements Implement Default, Position, Draft (EHC), Float
Draft Set-Point Hitch control Draft 1 kN to 60 kN
Application Rate Mounted sprayer 40 L/ha to 600 L/ha
Boom Lift Mounted sprayer 0 m to 0.6 m
Seeding Rate Seed drill 2 kg/ha to 400 kg/ha
Windrow Density Square baler 0 kg/m to 12 kg/m
Round Bale Mass Loader with bale fork 50 kg to 1200 kg

The menu examines the values. It shows a message when a depth is out of the range of the implement or when the axle loads are not safe. The setting Harvester and an implement cannot be on in the same session.

Set the Implement with Options#

The options replace the values of the menu and of tractor.json.

Name Type Unit Default Description
-Implement= string none Identifier of the implement.
-ImplementDepth= number m 0.15 Working depth of the cultivator, the chisel plow and the disc harrow. A negative value selects the design depth.
-HitchMode= string auto auto, position, draft or float. auto selects the default of the implement.
-DraftSetpoint= number N 15000 Draft set-point of the draft mode.
-SprayRate= number L/ha 150 Application rate of the sprayer.
-SeedRate= number kg/ha 150 Seed rate of the drill.
-WindrowDensity= number kg/m 3 Hay for each metre of windrow for the baler.
-BaleMass= number kg 450 Mass of a round bale for the loader.
-BoomLift= number m 0.5 Lift of the sprayer boom.
-ImplementSet= string Data keys of the implement file for this session.

Read the Implement Card#

The HUD shows a card for the implement on the right side. The key I shows or hides the work panels. Hold Tab to see all keys of the current implement.

Badge Meaning
Raised A mounted implement is in the raised position or in the transport state.
Working The tools are in the soil.
Relief Open A hydraulic ram cannot move its load. The relief valve is open.
Empty The hopper or the tank is empty.
PTO Too Slow The PTO of the baler turns at less than 900 rpm.

Each card ends with two rows. The row PTO shows the shaft speed and the power, or off. The row Hydraulics shows the hydraulic power and the mass of the implement.

Operate the Hitch#

The cultivator, the chisel plow, the disc harrow, the seed drill and the mounted sprayer are on the three-point hitch. A mounted implement starts in the raised position.

Key Function
Q Lower the implement to its working position, or lift it.
F Change the hitch mode: position, draft, float.
Up, Down Move the hitch lever. Up lifts the implement and decreases the depth.
Page Up, Page Down Increase or decrease the draft set-point by 1 kN.
O Set or release the transport state.
Hitch Mode Function Default For
Position The lever sets the height of the lift arms. Cultivator, chisel plow, mounted sprayer
Draft The hitch lifts the implement to hold the draft set-point. The lever is the depth limit.
Float The lift arms carry no load. The implement rests on its roller or wheels. Disc harrow, seed drill

The hitch lifts the implement automatically in reverse travel. The PTO stops when the lift angle is more than 20°.

Till with the Chisel Plow or the Cultivator#

The draft of a tine increases fast with the depth, and the draft makes the rear of the Maxxum go down. Use the draft mode for the chisel plow. Use the draft mode or a small depth for the cultivator.

  1. Start a session with the chisel plow in the draft mode.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=chisel_plow -HitchMode=draft \
    -DraftSetpoint=22000 -ImplementDepth=0.25 \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log contains ACRES_IMPLEMENT_READY id=chisel_plow with hitch_mode=1 and draft_setpoint_n=22000.

  2. Select gear 8 with ] and drive forward at 8 km/h.

  3. Push Q to lower the chisel plow.

    Expected Result

    The badge changes to Working. In a test run on field F39, the card showed these mean values:

    Row Value
    Depth 15.4 cm, setting 25 cm
    Draft 20.9 kN, down 9.7 kN
    Hitch draft, lift 7.0°
    Draft Control set 22.0 kN, sensed 22.3 kN

    The speed stayed at 7.8 km/h and the fuel flow was 18.8 L/h.

  4. Push Page Up or Page Down to change the draft set-point.

    Expected Result

    A larger set-point gives a larger depth, up to the depth limit of the lever.

  5. Push Q again to lift the chisel plow before a turn.

  6. Do the procedure again with the cultivator and a smaller draft set-point.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=cultivator -HitchMode=draft -DraftSetpoint=12000 \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    In a test run on field F39, the depth was 10.8 cm with the depth limit of 15 cm. The draft was 11.0 kN and the sensed draft was 12.0 kN. The speed stayed at 7.9 km/h and the fuel flow was 12.9 L/h.

CAUTION

Position mode holds the hitch angle. It does not measure the ground depth. Pitch and tyre sinkage can increase the depth. Use draft mode for these field runs. The Maxxum can stop in position mode.

In two test runs on field F39, the cultivator was in the position mode with settings of 8 cm and 15 cm. The depth increased to 28 cm in less than one second, and all nine tines tripped. The draft was approximately 30 kN, the engine speed decreased to 600 rpm and the Maxxum stopped. A repeat test held the hitch angle at 8.457° while the ground offset increased to approximately 20 cm. Draft mode at 12 kN gave a mean speed of 7.92 km/h and a mean depth of 10.37 cm. These means cover the last 5 s of a 25 s run.

When a tine hits hard soil, its spring lets it move back. The row Tines shows the number of tripped tines and the largest trip angle.

Operate the Disc Harrow#

The disc harrow operates in the float mode. The roller carrier sets the depth.

  1. Start a session with the disc harrow.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=disc_harrow \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log line ACRES_IMPLEMENT_READY id=disc_harrow contains roller_deg=8.41 and hitch_mode=2. The roller setting of 8.41° is the setting for the default depth of 15 cm.

  2. Drive forward at 8 km/h and push Q to lower the harrow.

    Expected Result

    In a test run on field F39, the card showed a depth of 6.3 cm and a draft of 11.5 kN. The fuel flow was 12.8 L/h. The depth was less than the setting. The lower links were at their lowest position for most of the run. A repeat test gave a mean depth of 6.55 cm. The ground was approximately 5.1 cm below the tractor reference plane.

  3. Push Down to turn the roller carrier up, which increases the depth. Push Up to decrease the depth.

Sow with the Seed Drill#

The seed drill operates in the float mode on its ground wheels. One ground wheel drives the seed meter.

  1. Start a session with the seed drill and a seed rate.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=seed_drill -SeedRate=150 \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log line ACRES_IMPLEMENT_READY id=seed_drill contains mass_kg=1737.5. This mass includes 487.5 kg of seed.

  2. Drive forward at 8 km/h and push Q to lower the drill.

    Expected Result

    The row Seed shows the seed mass in the hopper and the sown rate. The row Sown shows the area. In a test run on field F39, the sown rate was 149 kg/ha, the opener depth was 1.2 cm and the draft was 1.6 kN. A repeat test gave a mean depth of 1.00 cm, with the ground approximately 6.1 cm below the tractor reference plane. After 34 s, the sown area was 0.015 ha and the hopper contained 485 kg.

  3. Push T to stop or start the seed meter.

The drill does not sow in the raised position, in reverse travel or with an empty hopper.

Spray with the Mounted Sprayer#

The sprayer needs the PTO. Auto PTO stops the PTO while the sprayer is in the raised position.

  1. Start a session with the sprayer, an application rate and a boom lift.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=mounted_sprayer -SprayRate=150 -BoomLift=0.5 \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log line ACRES_IMPLEMENT_READY id=mounted_sprayer contains mass_kg=1070.0 and pto_ratio=0.2743. The mass includes 800 kg of liquid.

  2. Push Q to lower the sprayer to its lever position.

  3. Push E to engage the PTO.

    Expected Result

    The hand throttle increases the engine speed, and the row PTO shows the shaft speed. The rated speed of 540 rpm is at an engine speed of 1969 rpm.

  4. Drive forward at 8 km/h and push T to open the valves.

    Expected Result

    Spray fans show below the nozzles. In a test run, the row Rate showed 150 L/ha and the PTO used 0.6 kW at 570 rpm. After 33 s, the sprayed area was 0.085 ha and the tank contained 787 L.

  5. Push T to close the valves at the end of the pass.

  6. Push Y to fold the boom for transport. Push Y again to open it.

    Note

    The sprayer does not spray while the boom is not fully open.

The nozzles operate between 1 bar and 5 bar. With 150 L/ha, this is a speed range of 5.5 km/h to 12.4 km/h.

Move a Bale with the Loader#

The game puts two round bales 7.5 m and 12 m in front of the start position.

  1. Start a session with the loader and a bale mass.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=loader_bale_fork -BaleMass=450 \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log line ACRES_IMPLEMENT_READY id=loader_bale_fork contains mass_kg=820.0.

  2. Drive slowly to a bale until the fork is in the bale.

  3. Push G to take the bale.

    Expected Result

    The row Load shows round bale 450 kg. The mass in the row Hydraulics increases from 820 kg to 1270 kg.

  4. Hold Up to lift the boom. Hold Right to curl the fork back.

    Expected Result

    The row Boom shows the lift angle and the curl angle. The row Pressure shows the ram pressure, approximately 22 bar for this bale. The lift is slow at idle speed. Increase the hand throttle with = for a faster lift.

  5. Drive to the unload position, hold Down to lower the boom and push G to release the bale.

    Expected Result

    The bale falls from the fork and stays on the ground.

The loader takes a bale only when the bale is less than 1.3 m from the load point of the fork.

Dig with the Backhoe#

Park the Maxxum before you dig. The backhoe is behind the rear axle.

  1. Start a session with the backhoe.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=backhoe_attachment \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

  2. Push P to set the park brake and B to lower the stabilizers.

    Expected Result

    The row Stabilizers shows down and the load of each foot.

  3. Hold Down to lower the boom until the bucket is in the soil.

  4. Hold End to pull the dipper in and Page Down to close the bucket.

    Expected Result

    The row Bucket shows the soil mass in the bucket. The row Digging shows the tip depth and the dig force. In a test run, the bucket took 123 kg of soil in 4 s at a tip depth of up to 46 cm. A pit stayed in the ground.

  5. Hold Up to lift the boom. Hold Left or Right to swing the arm.

  6. Hold Page Up to open the bucket.

    Expected Result

    The bucket empties when it is open above the ground. The soil makes a spoil pile.

  7. Push O to move the arm to the transport pose before you drive.

Make Bales with the Square Baler#

The baler needs the PTO at 1000 rpm and a speed that gives 12 kg/s of hay or less.

  1. Start a session with the baler and a windrow density.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=square_baler -WindrowDensity=6 \
    -VehicleSpawnU=740 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log line ACRES_IMPLEMENT_READY id=square_baler contains mass_kg=6900.0 and pto_ratio=0.5283.

  2. Push E to engage the PTO.

    Expected Result

    The hand throttle increases the engine speed, and the row PTO shows the shaft speed. The rated speed of 1000 rpm is at an engine speed of 1893 rpm.

  3. Push Q to lower the pickup.

  4. Drive forward at 6 km/h.

    Expected Result

    The row Pickup shows the crop flow. The row Bales shows the mass of the bale in the chamber. The row PTO shows a power that changes with each stroke of the plunger.

  5. Continue until the first bale falls from the chute.

    Expected Result

    A bale stays on the ground behind the baler, and the row Bales shows 1 dropped. The log contains this line.

    ACRES_BALE_DROPPED index=1 mass_kg=311.0 at_m=(443.97, -73.16, 1.34)

    In a test run with a windrow of 6 kg/m, the crop flow was 9.1 kg/s and the first bale fell after 63 s. The PTO turned at 1120 rpm with a mean power of 63 kW. The plunger force had peaks of 360 kN.

Note

The pickup takes no crop while the flywheel turns at less than 900 rpm. The badge PTO Too Slow then shows.

Repeat a Run with a Drive Script#

A drive script sets the same controls as the keyboard at fixed times. Use it for runs that you must repeat.

  1. Write this file as chisel.json.

    {"frame": "spawn", "path": [[0, 0], [150, 0]],
 "keys": [
  {"t": 0, "gear": 8, "speed_kmh": 0, "raise": true},
  {"t": 3, "speed_kmh": 8},
  {"t": 6, "raise": false},
  {"t": 40, "exit": true}]}

  2. Run the script with a session log.

    Packaged/Linux/Acres.sh -VehicleDemo -RenderOffscreen -Implement=chisel_plow -HitchMode=draft \
    -DraftSetpoint=22000 -ImplementDepth=0.25 \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0 \
    -SessionLog -VehicleOutput="$PWD/chisel-run" -DriveScript="$PWD/chisel.json"

    Expected Result

    The game stops after 40 s of simulation time. The log contains these lines.

    ACRES_DRIVE_SCRIPT keys=4 path_points=2 file=.../chisel.json
ACRES_IMPLEMENT_READY id=chisel_plow keys=67 mass_kg=1100.0 com_m=(-1.347, 0.000, 1.066) width_m=2.70 depth_range_m=0.000-0.279 lever=0.053 roller_deg=2.00 hitch_mode=1 draft_setpoint_n=22000 pto_ratio=0.0000
ACRES_DRIVE_SCRIPT_DONE t=40.00

    The folder chisel-run contains tractor.csv with 4801 rows and session-summary.json.

  3. Read the implement columns of tractor.csv.

    Column Content
    implement_depth_m Mean depth of the tools.
    implement_draft_n, sensed_draft_n Draft of the implement and draft in the lower links.
    hitch_mode, hitch_lever, hitch_lift_deg State of the hitch.
    tines_tripped, trip_max_deg State of the tine trips.
    implement_pto_kw, implement_hydraulic_kw, implement_draft_kw Power of the implement.

The Session Log lists all columns. The Command-Line Options list all keys of a drive script. The implement keys of a drive script are in the tables of the Implement Catalog.

Change a Parameter for One Session#

The option -ImplementSet= changes data keys of the implement file for one session. Divide the keys with semicolons.

  1. Start a session with two changed keys.

    Packaged/Linux/Acres.sh -VehicleDemo -Implement=chisel_plow -ImplementDepth=-1 \
    "-ImplementSet=control.draft_gain_deg=8;hitch.drop_rate_deg_s=6" \
    -VehicleSpawnU=745 -VehicleSpawnV=452 -VehicleSpawnYaw=0

    Expected Result

    The log line shows 69 keys: the 67 keys of the file and the two keys of the option. The lever position of 0.144 is the position for the design depth of 0.20 m, because the depth option is negative.

    ACRES_IMPLEMENT_READY id=chisel_plow keys=69 mass_kg=1100.0 com_m=(-1.347, 0.000, 1.066) width_m=2.70 depth_range_m=0.000-0.279 lever=0.144 roller_deg=2.00 hitch_mode=0 draft_setpoint_n=15000 pto_ratio=0.0000

The game stops with the message rejected <key> = <value> when a key is unknown or a value is out of its limits. Implement Mechanics and the Implement Catalog list the keys.

Next Steps#