Introductory ABBs & PBAMs

Introductory ABBs & PBAMs

This page gives a few ABBs and PBAMs which introduce constrained object (cob) concepts progressively. More primitive ABBs are given first which are used to build subsequent ABBs and PBAMs.

Analysis Building Blocks(ABBs)
Represenation of engineering analysis concepts as cobs.

Spring

One D Linear Elastic Model

Extensional Rod

Uses One D Linear Elastic Model

Elementary Deformable Body

PBAMs
Represenation of engineering analysis models as cobs that includes explicit associativity between detailed design objects (CAD) and analysis objects (ABBs - for CAE).

Component Extensional Model

Uses Extensional Rod with "no force" condition
Includes STEP EXPRESS lexical form (early-bound approach)
Includes current Smalltalk form (in DaiTools)

Linkage Extensional Model

Uses Extensional Rod with "isothermal" condition
(demonstrates ABB reuse by diverse product applications)

PWB Thermal Bending Model

Includes STEP EXPRESS lexical form (early-bound approach)

Other PBAM Examples (include FEA-based and nested PBAMs)

Solder Joint Deformation PBAMs
Solder Joint Fatigue PBAM (uses Solder Joint Deformation PBAMs)

ABBs

One D Linear Elastic Model
Constraint Schematic

ABB Structure

Superclass

none

Variables

youngs modulus,
poissons ratio,
cte,
shear modulus,
strain,
elastic strain,
thermal strain,
stress,
shear strain,
shear stress,
temperature change,

Relations

r1
r2
r3
r4
r5

Subsystems

none
Subsystem Views (Special Cases)

full

isothermal

no shear

Extensional Rod

Constraint Schematic

ABB Structure

Superclass

Elementary Deformable Body

Variables

undeformed length,
area,
start,
end,
length,
total elongation,
force,
youngs modulus,
cte,
strain,
elastic strain,
thermal strain,
stress,

Relations

r1
r2
r3
r4

Subsystems

deformation model : One D Linear Elastic Model (no shear)

Subsystem Views

full

isothermal

no force

Elementary Deformable Body
ABB Structure

Superclass

none

Variables

reference temperature,
temperature,
temperature change,

Relations

Subsystems

material model : One D Linear Elastic Model

Subsystem Views

not applicable (abstract superclass)

PBAMs

Component Extensional Model

Constraint Schematic

Express

ENTITY component_extensional_model
SUBTYPE OF ( product_model_based_analysis_model );
	(* Product Variables *) 
		component : electrical_component;
	(* Subsystems *)
		deformation_model : basic_rod;
	(* Analysis Variables *)
		(* none extra *)
	(*Mapped Variables *)
		length : positive_length_measure;
		cte : cte;
		reference_temperature : temperature;
		temperature : temperature;
		temperature_change : temperature;
		total_elongation : length_measure;
		strain : strain;
WHERE
	(* Associativity Linkages*)
		al1 : deformation_model.length = component.total_length;
		al2 : deformation_model.cte =
			component.primary_structural_material.linear_elastic_model.cte;
	(* Analysis-Analysis Transformations *)
		(* none extra *)
	(* Subsystem Conditions *)
			(*
		ssc1 : deformation_model.no_force = true;
			*)
	(*Mappings *)
		mv1 : length = deformation_model.length;
		mv2 : cte = deformation_model.cte;
		mv3 : reference_temperature = deformation_model.reference_temperature;
		mv4 : temperature = deformation_model.temperature;
		mv5 : temperature_change = deformation_model.temperature_change;
		mv6 : total_elongation = deformation_model.total_elongation;
		mv7 : strain = deformation_model.strain;
END_ENTITY;

Smalltalk

"analysis variables" variables := nil. productVariables := List withAll: #(#component ). subProductVariables := Dictionary new. subProductVariables at: #component.totalLength put: #analysisVariable; at: #component.primaryStructuralMaterial put: #productVariable; at: #component.primaryStructuralMaterial.stressStrainModel put: #abb; at: #component.primaryStructuralMaterial.stressStrainModel.cte put: #analysisVariable. self addSubsystemSpec: #deformationModel type: BetterRod. mappedVariables := Dictionary new. mappedVariables at: #undeformedLength put: #deformationModel.undeformedLength; at: #cte put: #deformationModel.cte; at: #referenceTemperature put: #deformationModel.referenceTemperature; at: #temperature put: #deformationModel.temperature; at: #temperatureChange put: #deformationModel.temperatureChange; at: #totalElongation put: #deformationModel.totalElongation; at: #strain put: #deformationModel.strain. relations := nil. productAnalysisTransformations := Dictionary new. productAnalysisTransformations at: #al1 put: '#deformationModel.undeformedLength = #component.totalLength'; at: #al2 put: '#deformationModel.cte = #component.primaryStructuralMaterial.stressStrainModel.cte'.

Linkage Extensional Model

Constraint Schematic

PWB Thermal Bending Model

See Figures 6 & 7 in [Peak, et al., 1996] and U-Engineer for further explanation.

Constraint Schematic

Express

ENTITY pwb_thermal_bending_model
	SUBTYPE OF (pwb_warpage_model);
	(* Product Variables *)
		pwb : pwb; 
	(* Subsystems *)
		deformation_model : thermal_bending_system;
	(* Analysis Variables *)
		(* none *)
	(*Mapped Variables *)
		length : positive_length_measure;
			thickness : positive_length_measure;
		coefficient_of_thermal_bending : REAL;
		temperature : temperature;
		reference_temperature : temperature;
		temperature_change : temperature;
		warpage : length_measure;
	WHERE
	(* Associativity Linkages *)
		al1 : deformation_model.length = pwb.total_diagonal;
		al2 : deformation_model.thickness = pwb.total_thickness;
		al3 : deformation_model.coefficient_of_thermal_bending = 
			pwb.coefficient_of_thermal_bending;
	(* Analysis-Analysis Transformations *)
		(* none *)
	(* Subsystem Conditions *)
		(* none *)
	(* Mappings *)
		mv1 : warpage = deformation_model.total_deflection;
		mv2 : length = deformation_model.length;
		mv3 : thickness = deformation_model.thickness;
		mv4: coefficient_of_thermal_bending = 
			deformation_model.coefficient_of_thermal_bending;
		mv6 : reference_temperature = deformation_model.reference_temperature;
		mv7 : temperature = deformation_model.temperature;
		mv8 : temperature_change = deformation_model.temperature_change;
END_ENTITY;