When the Calculation Is Only as Good as the Data Behind It
Structural analysis, load path design, lifting plan engineering, spacecraft mass budgets — any discipline that cares about where mass sits in space needs accurate component-level data. The aerospace engineer calculating moment arms for a satellite payload, the naval architect checking stability limits for a vessel modification, the crane operator planning a lift with an off-centre load — they all need the same thing: mass in kilograms and the coordinates of where that mass acts.
This template is the structured inventory that feeds that calculation.
Mass, Amount, Total: The Arithmetic That Has to Be Right
Mass [kg] and Amount. Total mass is calculated — mass times quantity. Simple, but the simplicity matters. When twenty components go into a system and you're calculating the overall mass budget, every manual multiplication is an opportunity for error. When the template calculates it and you sum the total mass column, you have a traceable audit trail: each component's individual mass is in the record, the quantity is in the record, and the product is automatic.
The Part of inventory choice field categorises the component within a larger inventory structure — structural, propulsion, electrical, payload, mechanical. When you filter by category and sum total mass, you have the mass breakdown by subsystem. That breakdown is what the systems engineer needs for the mass budget spreadsheet, and it's what the lifting engineer needs to calculate the combined centre of gravity for the lift plan.
X, Y, Z COG: The Three Coordinates That Locate Mass in Space
x_cog, y_cog, z_cog — three double-precision coordinate fields. The coordinate system reference is established in the Meshgrid field: a text description of the origin point, axes orientation, and units that every calculation in the database must share. Without a consistent coordinate reference, individual component COG coordinates can't be combined into a system-level COG calculation.
The "Using the meshgrid" boolean flags whether the component's COG has been located within the reference frame or whether it's been estimated. When you're building a complex assembly and some components have precise COG data from the manufacturer's drawings and others are rough estimates based on geometry, the boolean lets you filter for unconfirmed data before finalising the analysis.
Comment Field, Three Images, One Date
Comment captures the data source — manufacturer datasheet, weighing, FEA result, estimated from density and volume. The provenance of the mass data matters when the analysis is used for a safety-critical calculation. If the project ever gets audited, the comment field is how you demonstrate that the 47.3 kg entry for the main structural frame came from the physical weighing record on a calibrated scale on March 14th, not from a sticker on the packing crate.
Three image slots: the component itself, its installation location in the assembly, and any dimensional or technical drawing that supports the COG coordinates. When a new engineer joins the project and needs to understand why a specific component's COG is where it is, the image of the drawing with the centroid marked is faster than reading three paragraphs of explanation.