Space truss span grammar problem

A bounded 3D space-truss grammar for adding joints and members inside a bridge-like envelope.

See Grammar Problem Catalog for the grammar family index.

Quick Facts

Field	Value
Problem ID	space_truss_span
Problem Family	grammar
Implementation	design_research_problems.problems.grammar._space_truss:SpaceTrussSpanProblem
Capabilities	discrete-actions, external-adapter, optional-evaluator, serializable-state, statement-markdown
Study Suitability	none
Tags	grammar, truss, 3d, discrete, topology

Taxonomy

Formulation

discrete_grammar

Convexity

not_applicable

Design Variable Type

discrete

Is Dynamic

no

Orientation

engineering_practical

Feasibility Ratio Hint

0.1

Objective Mode

single

Constraint Nature

hard

Bounds Summary

bounded 3D topology over a fixed span, width, and height envelope

Tags

grammar, truss, 3d, discrete, topology

Statement

Create a stable, lightweight 3D space truss spanning a fixed distance between four support joints. The grammar begins with a bridge-like support frame and a loaded apex joint. Designers can add interior joints inside a bounded 3D envelope, add members, and remove members.

States are evaluated by translating the library-owned grammar state into a fresh trussme.Truss, applying the load, and attempting a structural analysis. Singular or unstable states are treated as infeasible results.

Problem Shape

Field	Value
State Type	SpaceTrussState
Initial Transition Count	14
Initial Rule Names	add_joint, add_member

Manifest Parameters

Key	Value
candidate_point_fractions_3d	[[0.25, -1.0, 0.5], [0.25, 1.0, 0.5], [0.75, -1.0, 0.5], [0.75, 1.0, 0.5]]
load_magnitude	1000
max_height	5
span	10
width	4

Initial Transition Summary

Rule Name	Transition Count
add_joint	4
add_member	10

Library Interface

• initial_state()

• enumerate_transitions(state)

• enumerate_next_states(state)

• evaluate(state)