Event rigging and structural analysis

Concept: Braceworks structural analysis

The design of rigging structures is an integral part of the event, entertainment, display, and exhibit industries. The Braceworks® suite of commands and tools inserts and connects rigging objects (such as trusses and lighting pipes), adds hoists and other supports, and then adds loads to the structures.

With a Braceworks license, the system uses Finite Element Analysis (FEA) to accurately calculate and analyze the structural forces of a hanging rigging system, to determine whether the system is viable. Structural reports and the ability to export in DSTV or SCIA format allow the calculations to be shared and validated by structural engineering colleagues.

Braceworks-only functionality

Vectorworks Spotlight incorporates many of the Braceworks features for drawing rigging structures and adding loads, allowing Spotlight users to take advantage of the rigging tools and run a system check (a Spotlight user may need to add the available commands to the workspace).

However, a Braceworks license is required to perform calculations and create reports.

The structural analysis calculations in Braceworks are done by an FEA core that performs calculations upon the rigging objects in the Vectorworks drawing (the truss, straight truss, curved truss, lighting pipe, and lighting pipe ladder). Each object is handled individually in the calculations; the FEA core considers the hinge trusses as joints and all other truss, pipe, and ladder elements as beams. To determine the correct type of beam or joint, each object contains the cross section information required for proper calculations.

Commands that require a Braceworks license

Calculate All Objects

Calculate Load Combinations

Calculate Visible

Calculate Selection

Export Braceworks Structure

Create Calculation Report

Calculation Overview

Scale Influence Lines

Workflow: Working with Braceworks

In conjunction with Spotlight’s other tools, commands, and features, lighting designers can use Braceworks tools as part of the design process, and rigging professionals can use the Braceworks tool set and commands to create, analyze, and report complete rigging designs. The suggested workflow will vary, depending upon the type of design, the venue, the event, and whether you have a Spotlight or Braceworks license.

Creating a venue file

At the start of rigging project, create a venue file (or “house file”) that establishes the rigging points. This file can be reused to rig other events in the same location.

Specify the basics of the drawing: set the layer scale, create layers, set up Spotlight preferences, and so on.

Create layers to suit your rigging needs. To rig a trade show, for example, place each booth on a separate design layer. Paperwork can be organized by layer to create a parts list for each booth.

Model the venue space, including the walls and permanent stage pieces.

Use the House Rigging Point tool, the Insert House Rigging Point at Selection command, and the Structural Member tool to define the available rigging points. If the existing points are inadequate, use the Mother Grid tool to place a truss system in the drawing.

Define the load limits for the house rigging points by setting their Allowable Force values.

Braceworks for lighting designers

Lighting designers can set up a file with Braceworks with little change to their current workflow. To reduce excess geometry, use the Truss, Straight Truss, and Curved Truss tools as well as the Lighting Pipe and Lighting Pipe Ladder tools to insert rigging objects. Lighting devices and other loads can attach directly to these objects. The Convert to Hanging Position command creates custom hanging positions from multiple rigging objects or other geometry.

Braceworks for rigging designers

Collaborate with all departments involved with rigging.

Optional: Set up the truss inventory with the truss types and different truss lengths available, by selecting the Replace Truss command and clicking Truss Inventory.

Define the Braceworks preferences.

Create the rigging structure in the drawing space. Insert trusses with the Truss tool. Auto Connect mode should be enabled so that the rigging elements create a system. Alternatively, use the Straight Truss tool and the Curved Truss tool. Insert lighting pipes with the Lighting Pipe tool and lighting ladders with the Lighting Pipe Ladder tool.

Braceworks treats the hinge trusses as joints, and the other trusses, pipes, and ladders as beams.

As needed, add connections between rigging objects. Use the Insert Drop command to automatically place a hoist for the connection. For finer control, use the Insert Connection tool to insert a hoist or truss cross connection.

If needed due to inventory restrictions or other requirements, replace parts of the truss line with different lengths of truss with the Replace Truss command, or replace one truss type with another with the Replace Truss Type command.

Use the Convert to Hanging Position command to group rigging objects into a single hanging position for lighting devices and other load objects.

Have various departments add the load objects, such as lighting devices, speakers, video screens, and so on, or insert a point load or distributed load with the Rigging Load tool. The auto connect function snaps the load to the correct point.

Any elements that are not needed for calculations (Braceworks required) should be kept on layers that are separate from the elements that will be calculated.

Use the Hoist tool and Bridle tool to create the rigging supports.

Run the system check commands (first on selected objects, and then on all objects) to find any mistakes, such as unattached loads or hoists, and misaligned or unsupported objects.

Braceworks required: Correct any mistakes found. Braceworks provides color-coded annotations to assist with this, both in reports and within the drawing.

Braceworks required: Hide the layers that do not participate in calculations, and then run the calculations first on a subset of objects with the Calculate Selection command, and then on all visible objects with the Calculate Visible command.

Braceworks required: Run the calculations on all rigging objects with the Calculate All Objects command to determine the viability of the system.

Make changes to the system as needed.

Create schematic views for the rigging and load objects.

Export the necessary paperwork for hoist and bridle layouts; use the Create Hoist Report command, the Create Bridle Report command, and Create Bridle Assembly Diagrams command.

Braceworks required: Create a report of the calculations.

Braceworks required: Export reports if needed, sharing the data (PDF, DSTV, or SCIA file) with structural engineers, colleagues, or clients.