HKSM

An immersive, interactive simulation used to visualize work and test task flows so teams can estimate the people, equipment, and materials required. It helps validate crew sizes, equipment choices, and logistics before committing to the plan.

Key Points

• Used to rehearse activities in a simulated environment and translate observations into resource quantities and skill needs.
• Most valuable where space, access, safety, and sequencing drive effort (e.g., construction, manufacturing, warehousing, healthcare installs).
• Provides measurable evidence such as time-on-task, reach, clearances, collisions, and handling paths.
• Complements expert judgment, analogous, and parametric estimating; it does not replace them.
• Requires a workable 3D model or digital twin and structured facilitation with subject-matter experts.
• Improves confidence in estimates and clarifies assumptions captured in the basis of estimate.

Purpose of Analysis

To de-risk resource estimates by testing how work will actually be performed within real-world constraints. VR uncovers hidden labor, equipment, and material needs caused by access limits, ergonomics, safety zones, and logistics.

• Validate crew sizes and skill mix for each activity.
• Confirm equipment types, reach, capacity, and placement.
• Identify temporary works, staging, and material handling requirements.
• Estimate setup/teardown effort and shift patterns needed to avoid conflicts.
• Expose risks that drive contingency or alternative methods.

Method Steps

• Frame the estimation questions: which activities, constraints, and decisions need evidence.
• Assemble assets: WBS activities, preliminary resource list, 3D model/BIM or CAD, process maps, safety and access rules.
• Build the VR scenario: import models, set scales, define task sequences, hazards, and waypoints.
• Facilitate SME walkthroughs: have craft leads, operators, and safety reps perform the tasks in VR.
• Capture measures: times, distances, reach checks, collisions, clearances, queue lengths, and utilization.
• Iterate alternatives: try different crew sizes, equipment, paths, shift windows, and layouts.
• Translate findings: convert observed productivity and constraints into resource quantities, skill profiles, and calendars.
• Document assumptions and uncertainties; update the basis of estimate and planning artifacts.

Inputs Needed

• Defined activities or user stories with acceptance criteria.
• Preliminary resource catalogs (labor roles, equipment types, material specs).
• 3D models or layouts (BIM/CAD), site constraints, and logistics plans.
• Historical productivity data or vendor specs for calibration.
• Safety, ergonomics, and regulatory requirements.
• Known constraints such as access windows, outage periods, and work hour limits.
• VR hardware/software and data capture templates for observations.

Outputs Produced

• Refined resource requirements per activity, including crew sizes and skill mix.
• Equipment selections with specifications, reach/access notes, and counts.
• Material handling and staging needs, including temporary works.
• Updated productivity rates, setup/teardown allowances, and shift patterns.
• Resource calendars and peak loading profiles.
• Assumptions, constraints, and estimation rationale added to the basis of estimate.
• Cost and schedule impacts tied to resource choices, plus risk updates and potential change requests.

Interpretation Tips

• Calibrate VR timing with historical data; use results as directional, then triangulate with other methods.
• Prioritize scenario fidelity where it influences effort (clearances, logistics), not cosmetic detail.
• Run multiple scenarios to test crew sizes, equipment options, and access windows.
• Include safety and operations SMEs to reveal hidden tasks and compliance-driven resources.
• Record what was assumed ideal versus variable; convert variability into ranges or contingency.

Example

A hospital project must install an MRI in a tight suite on level 3. The team loads the BIM into VR and rehearses the rigging path from loading dock to the room. The session reveals a doorway clearance issue requiring panel removal, a temporary floor spreader, and an additional rigger. It also shows the crane cannot set up during daytime due to traffic barriers, pushing a night shift. The resource estimate is updated with a five-person rigging crew, one night crane shift, temporary works, and two extra electricians for equipment power-up.

Pitfalls

• Over-trusting an uncalibrated model that misrepresents space or equipment behavior.
• Not capturing setup, permits, handoffs, or inspection time observed during VR sessions.
• Too few SMEs, leading to missed craft-specific tasks and safety needs.
• Focusing on visuals instead of measurable data that converts to resource quantities.
• Failing to document assumptions and limitations, making results hard to defend.
• Skipping alternate scenarios, resulting in a single-point estimate with hidden risk.

PMP Example Question

While estimating resources for installing new racks in a congested data center, the team worries about access paths, clearances, and the right crew size. Which technique will best validate crew and equipment needs by walking through the space and testing task flows before finalizing the estimate?

1. Parametric estimating using historical productivity rates.
2. Virtual reality simulation using the 3D model.
3. Bottom-up estimating from vendor quotes only.
4. Reserve analysis focused on schedule uncertainty.

Correct Answer: B — Virtual reality simulation using the 3D model.

Explanation: VR lets the team rehearse tasks in the actual layout, revealing access and handling constraints that drive crew and equipment choices. Parametric and bottom-up alone lack spatial validation, and reserve analysis does not determine resource quantities.