Getting Started¶

Requirements¶

Windows (Robot Structural Analysis Professional is Windows-only)
Autodesk Robot Structural Analysis Professional 2018 or later
Python 3.14+

Installation¶

pip install pyrobotstructural

Initialization¶

Before using anything else, call initialize() once with the path to Interop.RobotOM.dll. The only part of the path that typically needs updating between Robot versions is the year number:

import pyrobotstructural

dll_path = r"C:\Program Files\Autodesk\Robot Structural Analysis Professional 2026\Exe\Interop.RobotOM.dll"
pyrobotstructural.initialize(dll_path)

This loads the Robot COM module via pythonnet and stores it in a singleton so the call is a no-op if made more than once.

Creating an application handle¶

app = pyrobotstructural.RobotApp()

RobotApp connects to the running Robot instance and exposes four facades:

Property	Purpose
`app.model`	Create/edit geometry, sections, supports
`app.loads`	Load cases, combinations, applied loads
`app.query`	Read nodes, bars, cases, results
`app.view`	Viewport control and screenshots

Building a model¶

Nodes and bars¶

app.model.management.clear()

# Single node
app.model.geometry.add_node(1, 0.0, 0.0, 0.0)

# Multiple nodes — 2-D list [number, x, y, z]
app.model.geometry.add_node([
    [2, 3.0, 0.0, 0.0],
    [3, 6.0, 0.0, 0.0],
])

# Bars — [number, start_node, end_node]
app.model.geometry.add_member(
    [[1, 1, 2], [2, 2, 3]],
    material_name="S235",
    section_name="IPE 200",
)

Performance: bulk operations¶

Use begin_edit() when creating many objects at once. It wraps the operations in a single COM transaction, giving a 10–100× speed improvement for large models:

with app.model.begin_edit():
    for i, (x, y, z) in enumerate(node_coords, start=1):
        app.model.geometry.add_node([[i, x, y, z]])
    app.model.geometry.add_member(members_array, section_name="CHS 88.9x4")

Shells and cladding¶

# Shell panel
app.model.geometry.add_shell_by_contour(
    points=[[1, 0,0,0], [2, 5,0,0], [3, 5,5,0], [4, 0,5,0]],
    thickness=0.2,
    thickness_name="200mm",
    material_name="C25/30",
)

# Cladding (load-distributing surface, not meshed)
app.model.geometry.add_cladding(
    points=[[1, 0,0,3], [2, 5,0,3], [3, 5,5,3], [4, 0,5,3]],
    load_distribution="Two-way",
)

Supports¶

# Define a named support type
app.model.supports.define_nodal_support("Pinned", ux=1, uy=1, uz=1)
app.model.supports.define_nodal_support("Fixed", ux=1, uy=1, uz=1, rx=1, ry=1, rz=1)
app.model.supports.define_nodal_support("RollerZ", uz=1)

# Apply to nodes
app.model.supports.apply_node_support([1, 2], "Pinned")

Loads¶

# Create load cases
app.loads.cases.add_loadcase(
    "Self-weight", CaseNature.PERMANENT, CaseAnalizeType.STATIC_LINEAR, number=1
)
app.loads.cases.add_loadcase(
    "Live load", CaseNature.EXPLOITATION, CaseAnalizeType.STATIC_LINEAR, number=2
)

# Apply loads
app.loads.load.add_self_weight("Self-weight", objects="all")
app.loads.load.add_uniform_load("Live load", objects="all", loads=[0, 0, -5000, 0, 0, 0])

# Create a combination
app.loads.combinations.add_combination(
    comb_number=3,
    comb_name="ULS 1",
    label="3",
    comb_type=CombinationType.ULS,
    case_analize_type=CaseAnalizeType.COMB_LINEAR,
    factors=[(1, 1.35), (2, 1.5)],
    case_nature=CaseNature.PERMANENT,
)

Calculating and reading results¶

# Run analysis
app.calculate()

# Read bar forces at midspan
forces = app.query.results.get_forces(bar_number=1, case_number=2)
print(f"My = {forces.my:.1f} Nm")

# Read node list
nodes = app.query.nodes.get_all_in_list()

Accessing the raw COM API¶

If you need functionality not yet wrapped, access the underlying COM objects directly:

app._raw   # RobotApplication COM object → access app._raw.Project, etc.
app._rbt   # RobotOM module → access all COM interfaces and enums