By domain
Engineering
Everything in Nalanda that sits under engineering.
19 entries
Beams, columns, and buckling
A long slender member loaded in compression can suddenly bow sideways and collapse at a load far below the load that would simply crush its material, and buckling is the study of when and why.
7 min
ConceptBearings, bushings, and friction management
A bearing or bushing is the joint that lets one part rotate against another while a designer controls, rather than eliminates, the friction between them.
7 min
Mental modelConstraints, assumptions, and margins
A margin is the deliberate gap you leave between what a design must survive and what you actually believe it will face, sized to the uncertainty in what you believe.
6 min
ConceptEngineering as constrained choice
Engineering is the practice of finding the best available choice once physical law, cost, time, safety, and human capability have each ruled out some of what you originally wanted.
7 min
Mental modelFailure modes and graceful degradation
A failure mode is one specific way a function can stop doing what it is supposed to do, and graceful degradation is designing so that when a failure mode occurs, the system loses capability in a controlled way rather than becoming dangerous all at once.
6 min
ConceptFasteners and joints
Every joint, bolted, welded, riveted, glued, press fit, or snapped together, is a deliberate choice about how a load path crosses from one part into another, and the choice trades off strength, cost, and whether the joint can be made, inspected, and undone again.
7 min
Mental modelFunctional decomposition
Functional decomposition is breaking a desired outcome into the smaller functions that must all happen for it to occur, described by what each function does rather than by what part will do it.
7 min
ConceptGears, belts, chains, and transmissions
A gear, belt, or chain transmission trades rotational speed for torque, or torque for speed, in an exact ratio set by the size of the wheels it connects.
7 min
ConceptLevers, linkages, cams, and motion conversion
A lever, linkage, or cam uses pure geometry, not motors or electronics, to transform a given force or motion into a different force or a different, deliberately chosen path.
7 min
ConceptLoads, load paths, and free-body thinking
A load path is the actual route a force travels, member by member, from where it is applied to the ground or support that finally absorbs it, and free-body thinking is the method of isolating one member at a time to check whether that route can carry what is asked of it.
7 min
Mental modelPrototypes as questions
A prototype is not a small version of the final product, it is the cheapest object you can build that answers one specific uncertain question.
6 min
Mental modelRequirements and success criteria
A requirement is a single, checkable statement of what a design must achieve, written so that WHAT is fixed while HOW is left entirely open.
6 min
ConceptSafety factors and uncertainty
A safety factor is the ratio of the load a part is designed to survive to the load it is actually expected to carry, sized deliberately to absorb the variability in materials, manufacturing, loading, and analysis that no calculation can fully eliminate.
7 min
ConceptSprings, dampers, and suspension
A suspension pairs a spring, which stores energy and pushes back proportional to displacement, with a damper, which dissipates energy proportional to speed, so a vehicle can absorb a bump and then stop moving rather than bounce indefinitely.
7 min
Mental modelSystem boundaries and interfaces
A system boundary is the deliberately chosen line separating what you are designing from everything else, and an interface is every point where matter, energy, or information crosses that line.
7 min
ConceptTension, compression, bending, torsion, and shear
Every internal force a member carries can be sorted into five basic types, tension, compression, bending, torsion, and shear, and telling them apart is what lets you predict how and where a part will actually fail.
7 min
Mental modelTrade-off spaces and objective functions
A trade-off space is the set of designs where improving one property necessarily worsens another, and an objective function is the explicit rule you use to decide which point in that space you actually want.
6 min
ConceptTrusses, frames, and triangulation
A truss carries load through a rigid arrangement of triangles, so that nearly every member works only in tension or compression, letting a structure be strong while using far less material than a solid beam of the same span.
7 min
ConceptWheels, rolling resistance, and traction
A wheel trades most sliding friction for a much smaller rolling resistance, but the same contact patch must still provide, through static friction, all the traction a vehicle needs to accelerate, brake, and turn.
7 min