Traverse Closure & Bowditch Adjustment

Status: Research brief below. Replace this entire body with finished MDX when research is complete. Update description in frontmatter.

Paired tools: /tools/calculators/traverse-closure, /tools/calculators/bowditch-adjustment

AI research prompt

You are writing a Learn article for Surveying Core. Produce a single MDX-ready document (article body only, no YAML frontmatter). The article will be published at /learn/tools/traverse-and-bowditch and must pair with two calculators:

• Traverse Closure — /tools/calculators/traverse-closure
• Bowditch Adjustment — /tools/calculators/bowditch-adjustment

One article covers both topics because they form a single workflow: measure misclosure, then distribute it.

Audience

• Engineering surveyors running closed traverses for control or detail surveys
• Students learning traverse computation and adjustment
• Office technicians checking field books before adjustment software

Platform conventions (must match the tools)

• Legs defined by azimuth from grid north (clockwise, decimal degrees) and horizontal distance
• Closure sums ΔE = Σ(D sin θ), ΔN = Σ(D cos θ)
• Linear misclosure = √(ΔE² + ΔN²)
• Relative precision = perimeter / linear misclosure (express as 1:N)
• Bowditch (compass rule): distribute misclosure to each leg in proportion to leg length; corrections applied to ΔE and ΔN components, then recomputed bearing/distance per leg
• Article must explain this method; mention that least-squares/network adjustment exists but is out of scope for MVP

Scope — must cover

1. What a traverse is (open vs closed); focus on closed loop or closed link returning to start or known point
2. Field measurements that feed the calculation (angles/distances, stationing) — practical, not instrument manual depth
3. Traverse closure computation step-by-step: tabular leg listing, cumulative ΔE/ΔN, misclosure vector, perimeter, relative precision
4. Acceptance criteria for misclosure (typical relative precision targets for different survey orders — cite standards or textbook guidance; note local spec may govern)
5. Why adjustment is needed when misclosure exceeds acceptable tolerance
6. Bowditch adjustment — derivation intuition (not full least-squares math): proportional distribution by distance; show formulas for correction to each leg; show that adjusted traverse closes
7. Worked example: minimum 4-leg closed traverse with realistic bearings/distances, misclosure small but non-zero, full Bowditch table through adjusted coordinates
8. When Bowditch is appropriate vs when to use least-squares (brief comparison table)
9. Links to both tools in intro and conclusion

Out of scope

• Full least-squares / STAR*NET / error ellipses
• Vertical traverse, slope distances, and curvature/refraction (mention only)
• GPS network adjustment
• Legal boundary/adjoining traverse case law

Quality bar

• Cite primary sources (e.g. standard surveying texts, national guidance on traverse accuracy classes if available)
• No generic overview filler
• At least one complete numeric traverse from raw legs → closure → Bowditch-adjusted legs
• Include a sample results table (markdown table is fine in MDX) showing leg, bearing, distance, ΔE, ΔN, corrections, adjusted values
• Common errors: wrong closure sign, applying adjustment to angles before converting to components, using slope distance without reduction
• WCAG-friendly headings starting at ##

Deliverable format

Return MDX body only. Suggested outline:

1. Introduction (links to both calculators)
2. Closed traverses in engineering surveying
3. Computing traverse closure
4. Misclosure and relative precision
5. Is the traverse acceptable?
6. Bowditch (compass rule) adjustment
7. Worked example (closure + Bowditch)
8. Bowditch vs least-squares (brief)
9. Common errors
10. References
11. Next steps (tool links)

Target length: 1,800–2,400 words.