MSD Analysis

MSD Analysis

SkyReal includes tools for Musculoskeletal Disorder (MSD) analysis, allowing you to evaluate the ergonomic risk of a manikin's posture using the RULA (Rapid Upper Limb Assessment) standard. The MSD avatar displays different colors on its body according to its RULA score, providing a visual representation of posture quality and ergonomic risk.

MSD Avatar

[IMAGE: MSD avatar displaying color-coded RULA scores -- original at /pictures/v1.18/Avatar_MSD.png]

The MSD avatar is a specialized avatar [introduced in] version 1.18. It overlays color-coded regions on the manikin's body to indicate the RULA score for each body [area].

How to Use

MSD Actions

On any manikin, you can activate the following options:

• Activate MSD: Enable this option to display the MSD [overlay] on the selected manikin.

• Show Score: Enable this option to display the MSD score numbers on the selected manikin.

MSD Visual Score

Each MSD avatar displays a number corresponding to different action levels, indicating the urgency of intervention:

• 1--2: Acceptable posture -- no action required.

• 3--4: Investigate further and consider changes.

• 5--6: Changes needed soon.

• 7+: Immediate changes required.

[IMAGE: Detailed breakdown of MSD scoring on a manikin -- original at /pictures/v1.20/MSD_howTo.png]

Score Groups

• Group A contains the score for [each] arm (one score per arm).

• Group B contains the score for the trunk (neck, spine, [and] head).

Scores A and B are represented on the manikin with a single circle around the number, placed on the arms, chest, and back.

• Group C is calculated from the scores of Group A and Group B.

Score C is represented with a double circle around the number, placed on the chest and back. The maximum of the Group C scores is represented with three circles in the [center] of the chest and back.

RULA Method

The RULA (Rapid Upper Limb Assessment) method is an ergonomic assessment tool designed to evaluate the risk of musculoskeletal disorders in the upper limbs. It is particularly useful for assessing the posture, muscle use, and forces exerted by workers who perform tasks involving the upper body.

Key Components of RULA

• Posture Analysis

  • Upper Arm: Evaluates the position of the shoulder and arm. Positions are scored based on the angle of the arm relative to the body and whether it is raised or lowered.

  • Lower Arm: Considers the angle of the elbow and whether the arm is close to the body or extended outward.

  • Wrist: Assesses the angle and orientation of the wrist, including flexion, extension, and deviation.

  • Neck and Trunk: Although primarily focused on the upper limbs, RULA also considers the posture of the neck and trunk, as they influence upper limb positions.

• Muscle Use
  Evaluates static or repetitive muscle activity. Prolonged or repetitive muscle use increases the score.

• Force/Load
  Assesses the amount of force exerted by the upper limbs. Handling heavy loads or exerting significant force increases the risk and therefore the score.

Options and Settings

Using Different Measurement Methods

SkyReal's extensions allow you to set up custom measurement methods for avatars and MSD reports. You can configure MSD parameters in the manikin's settings panel, and each parameter you select will influence the final score calculation.

Tips

• Activate the MSD overlay early in your ergonomic session so you can see score changes in real time as you adjust the manikin's posture.

• Pay special attention to scores of 5 or higher -- these indicate postures that need changes soon or immediately.

• Use the Group C score (displayed with a double circle) as your primary summary metric when comparing baseline and improvement postures.

• Combine MSD analysis with the Ergonomic Sessions workflow to generate comprehensive reports with scores, images, and comments.