WF03: Create FBD Model for Bond Simulations

Pre-requisites

• MADE Project: a configured project.
• Bill of Materials (BOM): establishes the system configuration to build the functional block diagram (FBD) model.

Detailed Descriptions (numbered steps)

1. Create model items with 'New Item' options under 'Modeling' in the main menu bar or via the right-click context menu opened on the system canvas.
2. Define General details in the Properties viewer, which overlaps with Advanced details accessed by 'Advanced Properties' via the right-click context menu opened on the model item. Also define Product Characteristics, if necessary.
3. Define function(s) in the Functions Editor, accessed by 'Functions' via the context menu opened on the model item. Click and drag relevant function from the Function taxonomy list onto the canvas.
4. Click and drag the relevant functional flows from the Functional Flow taxonomy list and place within the relevant function. Functional Flows are required for both in- and out-puts. Connect Flow Properties by clicking and dragging a connector from input Flow Property to output Flow Property.
5. Continue if a Bond Graph model is being created. If no, an FCM model is being created. Go to WF04.
6. Define the Bond Properties for the item by selecting the item in either the Project Explorer or on the System Canvas. Find the Bond tab within the Properties window and define a Bond Type and any further settings.
7. Continue creating all model items, defined with Functional Flows and Bond Properties.
8. Connect functional flows between model items by clicking and dragging from the output of one item, to the input of the other item. Only same functional flows will connect.
9. Access the Bond Model with 'Bond Graph' under 'Modeling' in the main menu bar. Select 'Verify Controllability' via the context menu opened in the bond graph canvas, to verify controllability.
10. If bond graph model fails to verify causality and controllability, alter it until successful, including creating model items.
11. To review bond response simulations, generate via the context menu opened on the target location and select the target bond response in 'Response Simulation'. Select additional bond responses to overlay on the graph.
12. If bond responses are unacceptable, alter the bond graph model until acceptable, including creating model items.
13. FBD Model for Bond Created.

Fields referenced in the diagram

• Define Model Item Details: General Properties, Advanced Properties, Product Characteristics
• Define Bond Properties: Bond Type, Passive Variables

Decision points

• Creating Bond Model? — No → Go to WF04; Yes → continue to Define Bond Properties.
• All Model Items Created? — No → loop back; Yes → continue.
• Bond Graph Model Verified? — No → alter model; Yes → continue.
• Responses Acceptable? — No → alter model; Yes → complete.

Outputs

• Bond Graph Model: representation of the FBD modelled for bond, exportable as a .png file.
• Bond Graph Equations: set of equations derived from the bond graph model.
• Bond Response Graphs: visual representation of the functional energy flow response simulations over time steps, exportable as .png files.

Screenshot walkthrough (captions/labels extracted)

Step 1: Create Model Item

• 'Modeling' menu: New Connection, New Item > (Part, Component, Subsystem), New RBD Group, Activate Failure Diagram, Functional Diagram, Mission Profile Definition, Requirements, System Environment, Unit Life Parameter.
• Right-click context menu on canvas: New > (Part, Component, Subsystem), Cut, Copy, Paste, Delete, Zoom In (Ctrl+=), Zoom Out (Ctrl+-), Propagate All...

Step 2: Define Model Item Details

• "Properties > General" table of fields by item level (System/Sub-system/Component/Part/Part-Pair): Item Name, Item Number, Physical Description, Functional Narrative, LCN, Critical Item, Safety Item, LRU/SRU, Instance Count.
• "Advanced Properties > Overview" table: Item Name, Item Number, LCN, Vendor Name, Vendor Number, Physical Description, LRU/SRU, Model Year/Program, Initial Operating Age (hrs), Synonyms, Documents, Drawing Reference Drawing, Reference Drawing, Digital Image, Icon.
• "Advanced Properties > Product Characteristics" table (columns System/Sub-system/Component/Part/Part-Pair): Design Description and Rationale, Failure History, Operational Use, Effects on Sub-system, Redundancy Screen (Sub-system), Pass/Fail (Sub-system), Acceptance, Qualification, Effects on Interface, Redundancy Screen (Interface), Pass/Fail (Interface), Receiving, Assembly/Installation, Testing, Contamination Control, Effects on Mission, Redundancy Screen (Mission), Pass/Fail (Mission), Effects on Human/System, Redundancy Screen (Human/System), Pass/Fail (Human/System).

Step 3: Define Function(s)

• 'Modeling' menu with Functions highlighted; Project Explorer context menu on a model item (e.g. "Differential") showing New > System Model, Failure Diagram, Functions (highlighted), Maintenance Actions, Cut/Copy/Paste, Delete, End Effect Item.
• "Functions" editor: tabs Functions / Flows; left taxonomy list includes Branch, Channel, Connect, Control (highlighted), Convert, Provide, Signal, Stop, Support. Canvas shows a "Divide" function block with IN FLOWS / OUT FLOWS panels.

Step 6: Define Functional Flows

• "Functions" editor showing "Divide" and "Control" function blocks. Left taxonomy: Energy > Acoustic, Chemical, Electrical, Electromagnetic, Generic, Hydraulic, Magnetic, Mechanical - rotational (highlighted), Mechanical - linear, Pneumatic, Thermal; Material; Signal > Continuous, Discrete, Generic.
• Second screenshot: "Divide" IN FLOWS = Mechanical - rotational with radio options Angular velocity / Torque; "Control" IN FLOWS = Mechanical - rotational (Angular velocity / Torque selected), OUT FLOWS = Mechanical - rotational (Angular velocity selected, connected from Torque).

Step 6 (second instance): Define Bond Equations

• "Properties" panel for "Planetary Gearbox Rear": tabs General, Bond (showing Function "Store" with Bond Type "1-IRC"), Equations, Functional Failures, Technical Property. Bond Type dropdown: "(1-IRC) Rotational Inertia Mass, Compliance and Resistance". Passive Variables table: Capacitor / Inductor / Resistor with rows Value (0.9 / 0.9 / 0.25), Initial Value (0.0 / 0.0 / —), Upper, Lower checkboxes.
• "Equations" tab expands a full equation tree under Store > 1-IRC (Rotational Inertia Mass, Compliance and Resistance) > 1 Junction > Inductor / Resistor / Capacitor, listing derived equations, e.g.:
  • 8.Flow = 8.Inductor State / 8.Inductance + Inductor initial condition
  • 9.Effort = 9.Capacitor State / 9.Capacitance + Capacitor initial condition
  • 17.Effort = 17.Flow * 17.Resistance
  • 8.Effort = 28.Effort - (17.Effort + 9.Effort + 29.Effort)
  • 8.Inductor State = Integral (8.Effort)
  • 9.Capacitor State = Integral (9.Flow)

Step 8: Connect Functional Flows

• Three progressive screenshots of the "Driveline" system canvas (Mission Profile: Regular Trip; End Effect Item: Vehicle System) showing model items Transmission, Driveshaft, Differential splitting into two parallel paths — Half Shaft Front → Planetary Gearbox Front → Wheel Front Resistance → Wheel Front, and Half Shaft Rear → Planetary Gearbox Rear → Wheel Rear Resistance → Wheel Rear — connecting to an "SE"/"IN" input block and "SES"/"OUT" output block via red functional flow connectors.

Step 9: Verify Bond Graph Model

• 'Modeling' menu with Bond Graph highlighted; Project Explorer tree expanded showing items (Coupling, Driveline, Differential, Half Shaft Front/Rear, Planetary Gearbox Front/Rear, Transmission, Wheel Front/Rear, Power, Diesel Engine components, Injector Pump, etc.).
• Bond graph canvas for "1↔ Vehicle System" shows the bond graph network with elements labeled C, I, R (capacitor/inductor/resistor icons) for Coupling, Transmission, Driveshaft, Differential, Half Shaft Front/Rear, Planetary Gearbox Front/Rear, Wheel Front/Rear Resistance, Wheel Front/Rear, connecting SE (source effort) and SES (sink) nodes. Right-click context menu: Zoom In (Ctrl+=), Zoom Out (Ctrl+-), Verify Controllability (highlighted), Propagate All...
• Result banner: "1↔ Bond Model is Controllable" shown above the diagram in both the "Vehicle System" tab view and a second view relabeled with SRC/SINK nodes and a legend: Peripheral Indenture, Current Indenture, Controllability Causality, Causality Error (color-coded).

Step 11: Review Bond Response Simulations

• Bond graph canvas context menu: Response Simulation submenu listing flow/effort variables (3E.Torque, 3F.Angular velocity, 13E.Torque, 13F.Angular velocity, 21E.Torque, 21F.Angular velocity, 22E.Torque, 22F.Angular velocity), plus Zoom In/Out, Verify Controllability, Propagate All.
• "Bond Response Simulation - Vehicle System" viewer: a checklist tree of variables (7F.Angular velocity, 8E.Torque, 8F.Angular velocity, 16E.Torque, 16F.Angular velocity, 22E.Torque, 23E.Torque, 23F.Angular velocity, Planetary Gearbox Rear > 5.Moment of inertia, 5.Moment of inertia state, 6.Compliance, 6.Compliance state, 15.Damping, 5E.Torque, 5F.Angular velocity, 6E.Torque (checked), 6F.Angular velocity (checked), 15E.Torque) and a response graph plotting selected variables against time, with a "FAILURE ACTIVATION" shaded region, y-axis from -0.05 to 0.225, x-axis 0-100, and end-value labels 0.125 and 5.0666E-7.

Step 13: FBD Model For Bond Created

• Final "Driveline" canvas showing the completed model: Transmission (1-R), Driveshaft (0-C), Differential (1-IR), splitting to Half Shaft Front (0-CR) → Planetary Gearbox Front (1-IRC) → Wheel Front Resistance (0-R) → Wheel Front (1-I), and Half Shaft Rear (0-CR) → Planetary Gearbox Rear (1-IRC) → Wheel Rear Resistance (0-R) → Wheel Rear (1-I), feeding into SE/IN and SES/OUT blocks.

Related workflows

• WF04 – Create FBD Model for FCM Simulations (branch taken if not creating a Bond model)