Sketch Constraints (Fusion 360)
Geometric constraints on sketch entities — coincident, horizontal, vertical, parallel, perpendicular, tangent, equal, midpoint, fix, symmetric, collinear, concentric.
Definition
Fusion 360 sketches use geometric constraints plus dimensions to fully define geometry. When a sketch is fully constrained, it turns black; under-constrained sketches show blue movable entities. The Auto Constraints feature applies likely constraints on the fly.
Why it matters
Fully defined sketches are deterministic — every dimension change produces a predictable result. Under-defined sketches drift in shape with parameter edits.
Common pitfalls
- Ignoring blue (under-defined) geometry and hoping it 'just works.'
- Over-constraining and getting redundant-constraint warnings.
- Mixing implicit auto-constraints with manual ones — produces unpredictable solver behaviour.
This concept is a core structural element of the Fusion 360 drafting and engineering environment developed by Autodesk. Autodesk's cloud-native unified design-and-make platform — parametric/direct hybrid modelling, CAM, sheet metal, simulation, electronics, and generative design in one subscription.
Relevant Fusion 360 FAQs
❓ Is Fusion 360 truly free for personal use?
Yes, but with restrictions. The personal-use tier is for hobbyists with under $1k/year in revenue from Fusion-created work. It limits active documents (10 editable at once), removes simulation/generative-design/electronics/extensions, simplifies CAM (no 5-axis, no multi-setup), and has restricted export options. Autodesk has progressively narrowed the free tier; verify current terms before relying on it commercially.
❓ What's the difference between Fusion 360 and Fusion Industry?
There is no separate 'Fusion Industry' product as of writing. 'Fusion 360' is the unified product. Extensions (Manufacturing, Simulation, Generative Design, etc.) add capability. Autodesk has also branded vertical packages (Fusion 360 with Inventor capability) at times; consult current Autodesk pricing pages.
❓ Can Fusion 360 work offline?
Yes — with caveats. Fusion caches files locally and supports a 'work offline' mode for up to 2 weeks. Cloud render, generative design, electronics simulation, and forced sync features require connectivity. For continuous offline work, Inventor is a better fit.
⚡ Concept Self-Test
🎓 Recommended Practice Lessons
Step-by-step practical exercises and certification-aligned paths chosen by our editors to master this concept:
Autodesk Certified Professional - Fusion 360 Exam Study Guide & Mock Practice
Fusion 360 Professional Design & Engineering Specialization
🌳 Semantic Crossroads & Navigation Pathways
Trunk-Branch-Leaf ModelCore glossary, interactive graph, and domain-wide concept index.
Parent design environments and platforms implementing this method natively.