Calculation methodology

Every bin has coordinates—and an exit test.

UnderBedFit is a bounded two-dimensional planning aid. It does not estimate frame strength, load capacity, floor deflection or whether a flexible product can be compressed.

Coordinate system

The top-left corner at the head-left side of the measured footprint is coordinate (0, 0). Width increases toward the right side and depth increases toward the foot. Every bin and obstruction is represented by an axis-aligned rectangle.

bin rectangle = (x, y, outside width, outside depth)

valid placement =
  rectangle stays inside the measured footprint
  AND does not overlap an obstacle
  AND does not overlap another bin

Vertical fit

usable vertical clearance =
  measured minimum clearance − safety buffer

bin passes height check when:
  outside bin height ≤ usable vertical clearance

Use the smallest floor-to-hardware height found beneath the frame. Handles, wheels and raised lid edges belong in the bin’s outside height.

Obstacles

A selected center rail becomes a full-depth rectangle centered in the measured footprint. The two-leg preset places square support footprints at one-third and two-thirds of the depth. Custom keep-clear zones use the visitor’s explicit left and head offsets.

Support-leg presets are illustrative because real frames vary. Offset, angled or additional hardware should be entered as custom keep-clear zones.

Candidate placement

UnderBedFit constructs deterministic candidate coordinates from the outer boundaries and the edges of existing obstacles and bins. It tests the original orientation and, when allowed, a 90-degree rotation. The search is intentionally capped at three bin types, three custom obstacles and forty placed bins.

The planner tries each ordering of the entered bin types and keeps the best result for three goals:

• Most storage: prioritizes placed count, then occupied floor area.
• Balanced: prioritizes count while strongly rewarding direct pull-out access.
• Easiest access: prioritizes bins with a straight route to an available edge.

Straight pull-out access

For each placed bin, the planner projects a rectangular corridor from the bin to every edge marked accessible. The corridor includes the user-entered pull-path buffer. A bin is “direct access” when at least one corridor reaches an open edge without intersecting another bin or obstacle.

The test assumes a straight horizontal slide. It does not model lifting, tilting, flexible containers, rugs, wall clearances or the room outside the measured footprint.

Area reporting

usable floor area =
  measured footprint − summed obstacle rectangles

occupied area =
  sum of placed bin footprints

floor coverage =
  occupied area ÷ usable floor area

Overlapping obstacle rectangles can make the displayed usable area slightly conservative. Bin placement itself still rejects the exact obstacle rectangles.

Limits and review policy

Rectangle packing is a complex optimization problem. UnderBedFit uses a transparent bounded heuristic, not a proof that no other arrangement exists. Results are deterministic for the same inputs, and warnings remain visible when requested quantities, height or retrieval conditions fail.

The method was last reviewed July 26, 2026. Corrections may be sent to support@aureliansyndicate.com.