Concepts Vehicle Modeling
This concepts page shows how the Vehicles and MachineModeling bundles can be combined to build a vehicle model from reusable parts, exported rigid bodies, and bundle-level axle/suspension connections.
The structure is inspired by the dump-truck tutorial, but the example below is kept closer to a single working OpenPLX file.
The main pattern is:
- define reusable tuning traits first
- define reusable wheel models
- reuse rigid-body traits exported from Blender
- assemble the final vehicle using
Vehiclesinterfaces andMachineModelingcomponents
Reusable traits and exported bodies
The Blender plugin can export rigid-body traits with mesh geometry and MateConnectors generated from mates defined in Blender.
Those exported connectors are then mapped to the connector roles required by the DumpTruck bundle interfaces.
The code below is intentionally shown as setup material only, so it does not get its own Open in Editor button.
trait Suspension:
front_axle_connection:
min_length: 0.4
stroke_length: 0.4
rod_diameter: 0.15
barrel_diameter: 0.20
rear_axle_connection:
min_length: 0.45
stroke_length: 0.4
rod_diameter: 0.15
barrel_diameter: 0.20
trait Hydraulic:
steering:
min_length: 0.941
stroke_length: 0.525
rod_diameter: 0.070
barrel_diameter: 0.150
ImportedTireVisual is Visuals.Geometries.ExternalTriMeshGeometry:
path: @"fr_wheel.obj"
Wheel is Vehicles.Wheels.Base:
rim.radius: 25.00 * 25.4e-3 / 2
rim.width: 25.00 * 25.4e-3
rim becomes Vehicles.Wheels.Rim:
geometry:
local_transform.rotation: Math.Quat.from_to({1, 0, 0}, {0, 0, 1})
radius: 1.870/2
visual is ImportedTireVisual
connector:
main_axis: -Math.Vec3.Y_AXIS()
normal: Math.Vec3.Z_AXIS()
Wheel_L is Wheel:
connector:
main_axis: -Math.Vec3.Y_AXIS()
normal: Math.Vec3.Z_AXIS()
Wheel_R is Wheel:
connector:
main_axis: Math.Vec3.Y_AXIS()
normal: Math.Vec3.Z_AXIS()
trait bodyBody:
b_frame_c is Physics3D.Interactions.MateConnector:
position: {0.000000, 0.000000, 0.000000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
l_lift_cyl_c is Physics3D.Interactions.MateConnector:
position: {-1.992000, -1.572000, 0.805000}
main_axis: {-0.366427, -0.930416, 0.007601}
normal: {0.388944, -0.160589, -0.907157}
r_lift_cyl_c is Physics3D.Interactions.MateConnector:
position: {-1.992000, 1.572000, 0.805000}
main_axis: {-0.366427, 0.930416, 0.007601}
normal: {-0.388944, -0.160589, 0.907157}
visual is Visuals.Geometries.ExternalTriMeshGeometry:
path: @"body.obj"
geometry is Physics3D.Geometries.ExternalTriMeshGeometry:
path: visual.path
trait f_axleBody:
f_frame_c is Physics3D.Interactions.MateConnector:
position: {0.000000, 0.000000, 0.000000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
fl_sus_pist_c is Physics3D.Interactions.MateConnector:
position: {1.345000, -0.680000, 0.200000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
fl_wheel_c is Physics3D.Interactions.MateConnector:
position: {1.345000, -1.345000, -0.000000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
fr_sus_pist_c is Physics3D.Interactions.MateConnector:
position: {1.345000, 0.680000, 0.200000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
fr_wheel_c is Physics3D.Interactions.MateConnector:
position: {1.345000, 1.345000, -0.000000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
visual is Visuals.Geometries.ExternalTriMeshGeometry:
path: @"f_axle.obj"
geometry is Physics3D.Geometries.ExternalTriMeshGeometry:
path: visual.path
trait f_frameBody:
kinematics.local_transform.position: {-1.165000, -0.000000, 0.710000}
f_axle_c is Physics3D.Interactions.MateConnector:
position: {-2.695000, 0.000000, 0.140000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
fl_sus_cyl_c is Physics3D.Interactions.MateConnector:
position: {-1.350000, -0.680000, 0.860000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
fr_sus_cyl_c is Physics3D.Interactions.MateConnector:
position: {-1.350000, 0.680000, 0.860000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
lower_hitch_c is Physics3D.Interactions.MateConnector:
position: {0.000000, 0.000000, 0.100000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
upper_hitch_c is Physics3D.Interactions.MateConnector:
position: {0.000000, 0.000000, 0.700000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
l_steer_cyl_c is Physics3D.Interactions.MateConnector:
position: {-1.0285000, -0.44001200, 0.440000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
r_steer_cyl_c is Physics3D.Interactions.MateConnector:
position: {-1.0285000, 0.44001200, 0.440000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
visual is Visuals.Geometries.ExternalTriMeshGeometry:
path: @"f_frame.obj"
geometry is Physics3D.Geometries.ExternalTriMeshGeometry:
path: visual.path
trait b_frameBody:
b_axle_c is Physics3D.Interactions.MateConnector:
position: {3.160000, 0.000000, -0.180000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
body_c is Physics3D.Interactions.MateConnector:
position: {5.120001, 0.000000, 0.643350}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
c_axle_c is Physics3D.Interactions.MateConnector:
position: {1.190000, 0.000000, -0.180000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
upper_hitch_c is Physics3D.Interactions.MateConnector:
position: {0.000000, 0.000000, 0.300000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
lower_hitch_c is Physics3D.Interactions.MateConnector:
position: {0.000000, 0.000000, -0.300000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
l_equalizer_c is Physics3D.Interactions.MateConnector:
position: {3.520000, -0.580000, 0.240000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
r_equalizer_c is Physics3D.Interactions.MateConnector:
position: {3.520000, 0.580000, 0.240000}
main_axis: {0.000000, -1.000000, -0.000000}
normal: {0.000000, -0.000000, 1.000000}
l_lift_pist_c is Physics3D.Interactions.MateConnector:
position: {0.586000, -0.535000, 0.150000}
main_axis: {-0.391978, 0.152884, 0.907182}
normal: {0.363190, 0.931715, -0.000091}
r_lift_pist_c is Physics3D.Interactions.MateConnector:
position: {0.586000, 0.535000, 0.1500000}
main_axis: {-0.391978, -0.152884, 0.907182}
normal: {-0.363190, 0.931715, 0.000091}
l_steer_pist_c is Physics3D.Interactions.MateConnector:
position: {0.011266, -0.294972, 0.120000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
r_steer_pist_c is Physics3D.Interactions.MateConnector:
position: {0.011266, 0.294972, 0.120000}
main_axis: {0.000000, 0.000000, 1.000000}
normal: {0.000000, 1.000000, 0.000000}
visual is Visuals.Geometries.ExternalTriMeshGeometry:
path: @"b_frame.obj"
geometry is Physics3D.Geometries.ExternalTriMeshGeometry:
path: visual.path
The important connector mapping idea is:
- the Blender-exported
MateConnectors preserve the attachment frames from the original CAD/Blender assembly - those connector names are then mapped into bundle-required roles like
upper_joint_connector,center_a_frame_connector, andleft_steering_actuator_connector - this lets the vehicle bundle work with authored geometry instead of rebuilding all connector placement by hand
Final dump-truck model
This is the final model block. It depends on the setup traits above, so Open in Editor should copy both the setup section and this final TutorialDumpTruck model into the editor.
TutorialDumpTruck is Vehicles.DumpTruck.Articulated:
with Vehicles.DumpTruck.Interfaces.FourWheels
with Hydraulic
left_front_wheel becomes Wheel_L
right_front_wheel becomes Wheel_R
left_rear_wheel becomes Wheel_L
right_rear_wheel becomes Wheel_R
chassis becomes Vehicles.Chassis.Articulated.DualPivot:
front_frame becomes MachineModeling.Components.Primitive.Base with Vehicles.Chassis.Articulated.Interfaces.DualJoint, Vehicles.Chassis.Articulated.Interfaces.DualSteeringActuators, Vehicles.DumpTruck.Interfaces.Chassis.AFrame:
body becomes Physics3D.Bodies.RigidBody with f_frameBody
upper_joint_connector: chassis.front_frame.body.upper_hitch_c
lower_joint_connector: chassis.front_frame.body.lower_hitch_c
left_steering_actuator_connector: chassis.front_frame.body.l_steer_cyl_c
right_steering_actuator_connector: chassis.front_frame.body.r_steer_cyl_c
center_a_frame_connector: chassis.front_frame.body.f_axle_c
rear_frame becomes MachineModeling.Components.Primitive.Base with Vehicles.Chassis.Articulated.Interfaces.DualJoint, Vehicles.DumpTruck.Interfaces.Chassis.AFrame, Vehicles.DumpTruck.Interfaces.CargoBed.SingleJoint, Vehicles.DumpTruck.Interfaces.CargoBed.DualActuator, Vehicles.Chassis.Articulated.Interfaces.DualSteeringActuators:
body becomes Physics3D.Bodies.RigidBody with b_frameBody
upper_joint_connector: chassis.rear_frame.body.upper_hitch_c
lower_joint_connector: chassis.rear_frame.body.lower_hitch_c
center_a_frame_connector: chassis.rear_frame.body.b_axle_c
cargo_bed_connector: chassis.rear_frame.body.body_c
left_steering_actuator_connector: chassis.rear_frame.body.l_steer_pist_c
right_steering_actuator_connector: chassis.rear_frame.body.r_steer_pist_c
front_wheel_axle:
body becomes Physics3D.Bodies.RigidBody with f_axleBody
center_a_frame_connector: front_wheel_axle.body.f_frame_c
left_wheel_connector: front_wheel_axle.body.fl_wheel_c
right_wheel_connector: front_wheel_axle.body.fr_wheel_c
rear_wheel_axle:
body becomes Physics3D.Bodies.RigidBody with f_axleBody
center_a_frame_connector: rear_wheel_axle.body.f_frame_c
left_wheel_connector: rear_wheel_axle.body.fl_wheel_c
right_wheel_connector: rear_wheel_axle.body.fr_wheel_c
steering:
left_steering_actuator becomes MachineModeling.Actuators.Linear.Cylinder with MachineModeling.Actuators.Linear.Traits.VelocityMotor
right_steering_actuator becomes MachineModeling.Actuators.Linear.Cylinder with MachineModeling.Actuators.Linear.Traits.VelocityMotor
front_axle_connection becomes Vehicles.DumpTruck.Connections.AFrame.Base:
chassis_frame: chassis.front_frame
a_frame: front_wheel_axle
left_axle_connector: front_wheel_axle.left_wheel_connector
right_axle_connector: front_wheel_axle.right_wheel_connector
rear_axle_connection becomes Vehicles.DumpTruck.Connections.AFrame.Base:
chassis_frame: chassis.rear_frame
a_frame: rear_wheel_axle
left_axle_connector: rear_wheel_axle.left_wheel_connector
right_axle_connector: rear_wheel_axle.right_wheel_connector
cargo_bed becomes MachineModeling.Components.Primitive.Base with Vehicles.DumpTruck.Interfaces.CargoBed.SingleJoint:
body becomes Physics3D.Bodies.RigidBody with bodyBody
cargo_bed_connector: cargo_bed.body.b_frame_c
cargo_bed_connection becomes Vehicles.DumpTruck.Connections.CargoBed.Fixed:
chassis_frame: chassis.rear_frame
cargo_bed: cargo_bed
This model is intentionally simpler than the full tutorial, but it keeps the same bundle-level idea:
Vehiclesprovides the vehicle interfaces and ready-made axle connection abstractionsMachineModelingprovides the component structure for the articulated chassis- Blender-exported rigid-body traits provide geometry and connector frames
- the final truck model just maps those parts together
