Tutorial 26: Crane Pick & Brace Simulation

Rehearse the lift before the field — run the pick simulation on your cast-yard set in cv-web, watch the crane pick the panels in 3D, and read where each pick sits against the crane’s reach and capacity.

Every tilt-up job ends the same way: a crane arrives, and one panel at a time is picked off the casting slab, swung, and set. The order the panels come off, where the crane stands, and how far it reaches decide whether that day runs smoothly. Crane pick & brace simulation is cv-web’s dress rehearsal for that day — a 3D playback of the lift built from your project’s own pick points, brace points, and cast-yard layout, so the sequence can be reviewed on screen before a crane is ever mobilized. This lesson walks one rehearsal end to end in the browser, building on the pick and brace points from Tutorial 9: Brace Points & Expansion Gaps and the casting layout from Tutorial 12: Construction Layout, carried into cv-web the way Tutorial 16: From CAD to cv-web describes.

Note

Preview feature — pilot-gated — U.S. Patent Pending. Crane pick & brace simulation is in preview: it runs in cv-web today for enrolled pilot accounts, and it unlocks with the AI entitlement on your membership (separate from panel-editing membership — an editing member who has not unlocked AI is prompted to unlock it). The technology is U.S. Patent Pending. Because it is still in preview, the exact on-screen controls and labels can change as it settles; this lesson teaches the workflow and what to look for, and stays conceptual where the interface is not yet fixed. Everything it reports is a planning aid, not an engineering determination — it does not replace the lift engineer’s rigging and bracing plan.

Warning

Crane stations and the slab edge — read this before copying any station shown here.

A crane station must sit entirely outside the wall-clearance standoff, on prepared subgrade, or entirely inboard of the closure strip, on the poured slab. Never between the two, and never spanning the boundary. The test is the machine’s bearing footprint — its tracks or outriggers — not the centre of a drawn circle. One track on poured slab and one on unpoured subgrade gives differential support under the mat; the slab edge spalls or the subgrade settles, and the machine goes out of level under load.

TCA Safety Guideline v13.1 (June 2013) §2 item 6, p.8: “Install entrance and exit ramps for the crane to position itself onto the floor slab. Do not allow the crane to exert its weight on the extreme edge of any portion of the slab.” See also OSHA 29 CFR 1926.1402 — ground conditions; the operator must be notified of bearing capacity, and the controlling entity is responsible for adequate site preparation.

Station placement in this release is a known open defect (CV-2714). The perpendicular standoff is a fixed value that every catalogued machine’s bearing footprint exceeds, so a generated station can straddle the boundary. Do not copy a station position from this lesson, or from its video, onto a real site. Have the setup reviewed against the machine’s bearing footprint and the site’s own closure-strip and brace-line dimensions.

And on this release the drawn frame can be mirrored, which makes an inside/outside verdict untrustworthy whenever it happens. It was measured in coordinates on a saved post-draw drawing rather than inferred: after Site Drawing Options is entered twice, wall-line ends land at the exact Y-mirror of their shipped positions – same X to the hundredth, Y negated – 622 feet apart at the widest, while a point at the origin separates by zero, which is what distinguishes a mirror from a constant shift. Two points were left unmoved, so this is a partial redraw and not a blanket transform of every coordinate. The no-flip control has since been run, and the frame flip IS the cause. An otherwise identical take with no Site Drawing Options entries drew ZERO mirrored points, with all four shipped points unchanged, while the flipped take mirrored two of them. The control was not a null run – it drew ten points against the shipped four, and left fourteen wall-line ends open against the shipped two – so the zero means something. The mirror is therefore not present on an untouched drawing – but the action that brings it on is smaller than it sounds: opening Site Drawing Options twice and then drawing is enough. Measured on the dialog itself, BOTH openings were closed with Esc – no OK, no edit, nothing typed. Backing out of the dialog still sets it. That is still ordinary use and still a defect, but it is narrower than the previous wording implied. The discriminator is clean and the sample is small – four shipped points, on staged copies rather than customer files. An earlier version of this note said the draw refused and therefore nothing reached the sheet; part of it drew, and what drew is mirrored.) So a station reported as clear of the closure strip may not be. Treat every crane position here as illustrative of the workflow only, never as a sited answer.

Scope, measured 2026-09-16: the footage on this page shows cv-web Cast-mode capacity rings in the casting yard, not stations placed on a site plan – 28 sampled frames across the four crane videos, none showing a slab edge or closure strip. The placement defect above is in the site-plan sequencer, so it is a caution about the workflow you are learning, not a statement about a picture on this page.

Note

This lesson also exists in the browser. Work it in ConstructiVision on the web — same steps, same values, so you can follow either and end up with the same panel.

What you will build

From your project’s cast-yard set in cv-web:

  • a pick simulation of the whole set — the crane picking the panels off the slab in a computed order, driven by your placed pick points and the panel weights and geometry;

  • a 3D dress rehearsal you can play, pause, and scrub — the lift running pick by pick so you can watch the swing and the reach the way the field will see it;

  • a per-pick read-out — arm rotation and reach, crane moves, rig changes, and each pick’s weight against the crane’s rated capacity at that radius, with any critical picks flagged for review;

  • a chosen pick order you can apply back to the layout, after comparing candidate orders the simulation proposes.

Before you start

  • A project in cv-web with a cast-yard layout. The simulation rehearses the casting-yard arrangement — the tipped-down set from Tutorial 12: Construction Layout. Bring your project into cv-web as Tutorial 16: From CAD to cv-web shows (sign in at simplestruct.com, import the project’s .cvp), or open a cloud project from Work with cloud projects.

  • Pick points and brace points on the panels. The rehearsal is only as real as the rigging it reads: place them first in Tutorial 9: Brace Points & Expansion Gaps so the crane has actual pick points to lift from and brace points to check.

  • A membership with AI unlocked, and pilot access. The simulation runs on SimpleStruct’s servers and reads the AI entitlement — see Analyze panel sets for how the preview AI features are gated and Membership & Tokens for what a membership includes. If AI is not unlocked, the simulation button prompts you to unlock it rather than running.

Tip

No cast-yard project of your own yet? Finish Tutorial 12: Construction Layout, export the project .cvp, and import it into cv-web per Tutorial 16: From CAD to cv-web. The rehearsal wants a set, not a single panel — the whole point is the order the panels come off.

Lesson

Step 1 — Open the casting-yard layout in cv-web

Sign in at simplestruct.com and open your project, then switch to its casting-yard layout — the tipped-down arrangement, not the standing site view. This is the same layout Tutorial 12: Construction Layout records in AutoCAD; in the browser it is the surface the crane rehearsal is built on. You should see every panel laid flat in its casting position, which is exactly what the crane will pick from.

Step 2 — Confirm the pick and brace points the rehearsal will use

Before running anything, spot-check that the panels carry their rigging. Each panel should show its pick points (where the crane’s rigging attaches to lift it) and its brace points (where the temporary braces will hold it plumb once it is standing). The simulation lifts from these exact points — if a panel is missing them, add them back on the CAD side per Tutorial 9: Brace Points & Expansion Gaps and re-import. Getting this right now is what makes the rehearsal a rehearsal of your lift rather than a generic one.

Step 3 — Run the pick simulation

Start the rehearsal from the layout’s Pick Simulation control. The run happens on the server, so it takes a moment — a progress state shows while it works, and the AI gate is checked first: if your membership has not unlocked AI, you are prompted to unlock it here instead of the run starting. When it finishes, cv-web has a computed pick sequence for the set and the geometry of the crane’s motion for each pick.

Step 4 — Watch the lift play back in 3D

Play the sequence back. A playback toolbar drives the dress rehearsal — play / pause, step forward and back one pick at a time, rewind, skip to start or end, and a speed control — so you can run the whole lift at speed or walk a single tricky pick frame by frame. Watch for what a field crew would watch for: a panel that swings far across others, a pick that reaches near the edge of the crane’s range, or a spot where the crane would need to pack up and move. Seeing it on screen is the whole value — the rehearsal makes the awkward moments visible while they are still cheap to change.

Step 5 — Read the pick metrics and critical-pick flags

Alongside the playback, the rehearsal reports the numbers behind the motion, per pick and across the set — including how far the crane arm rotates and extends, how many times the crane must move (mobilize), how many rig changes the sequence needs, the maximum reach (radius) any pick demands, and each pick’s weight against the crane’s rated capacity at that radius. A pick whose weight approaches capacity for its reach is flagged as a critical pick.

Read those flags exactly the way you read Panel Set Analytics placements — as prompts to look, not determinations. A critical-pick flag says this pick is close to the crane’s limit at that radius, check it; it is a planning proxy, not the lift engineer’s capacity check or rigging design. The simulation also watches for the crane body and rigging clashing with panels — again surfaced so a human can resolve it, never resolved silently.

Step 6 — Compare pick orders and apply one

The rehearsal does not just play one order — it proposes several candidate sequences and lets you compare them side by side, metric by metric, so you can favor the ones that matter for your crane and yard (fewer crane moves, less arm rotation, fewer rig changes). A Monte-Carlo pass samples many random orderings so the proposed sequences are read against a spread, not a single guess, and the comparison shows each metric as a typical value with its variability. When one order reads best for your priorities, apply it back to the layout — the set now carries that pick order, and the rehearsal you just watched is the plan you can share with the field.

Check your result

Tip

This lesson’s result lives entirely in cv-web in the browser — a preview run on SimpleStruct’s servers — so there is no AutoCAD CV-CHECK-LESSON command for it: the drawing-side lesson checker cannot see a web rehearsal. Check the outcomes themselves against the list below, and treat this as a preview run rather than a graded exercise.

You should be able to confirm all of the following:

  • Your project’s casting-yard layout is open in cv-web, with every panel showing its pick points and brace points.

  • A pick simulation completed — you have a computed pick sequence for the set (or, if AI was not unlocked, you saw the unlock prompt rather than a silent no-op).

  • The 3D playback runs: you can play, pause, step, and change speed through the lift.

  • The per-pick metrics are shown, and any critical picks are flagged — and you can state, in your own words, that a flag is a prompt to review, not an engineering or capacity ruling.

  • You compared candidate pick orders and applied one back to the layout.

If the simulation button prompts to unlock AI, or a run does not start, the entitlement and preview terms are in Analyze panel sets and Membership & Tokens; sign-in and browser trouble is in Troubleshooting → cv-web (simplestruct.com).

Watch this lesson

The video shows the Preview feature as it stands today; the pilot gate and patent notice above still apply.

Transcript (23 captions)

0:01 — Tutorial 26 — rehearse the lift before anyone mobilizes a crane. Preview capability, pilot-gated.

0:05 — Start from a sample building — a full multi-panel project, so there is something real to work with.

0:12 — ConstructiVision Sample Building — 60 panels. Nothing you do while looking around changes anyone's data.

0:17 — The cv-web editor, with a project open.

0:20 — Cast mode — the casting yard, where panels lie before they stand.

0:25 — Every panel gets a bed and a place in the pour.

0:29 — Order on the ground is order in the air. The last panel cast is often the first one picked.

0:35 — Pick order shows the sequence the crane will work in.

0:40 — Install arrows draw each panel's path from bed to final position.

0:44 — Capacity rings are the crane's reach at load — the radius where it can still lift this weight.

0:50 — A panel outside the ring is not a scheduling problem. It is a different crane, or a different bed.

0:57 — Wall clearance checks the swing against what is already standing.

1:00 — Pick animation walks the sequence so you can watch it, not just read it.

1:06 — This is the rehearsal — the whole construction sequence, before a single panel moves.

1:10 — Then run the simulation against the layout.

1:13 — It compares candidate sequences and reports what each one costs.

1:17 — Crane moves — every reposition of the machine itself, the most expensive thing on the site.

1:24 — Arm rotation and extension — the wear and the time.

1:28 — Rig changes — how often the crew has to re-rig between picks.

1:33 — Max radius and Total weight — the envelope the lift actually demands.

1:38 — Critical picks is the one to read first: the lifts with the least margin.

1:44 — A critical pick is not a failure. It is a lift that deserves a conversation before the morning it happens.

1:51 — Rehearsed in a browser, on the real panel set, at no cost — and changed while changing it is still cheap.

Where next