ACCELEROMETER DESIGN LAB
Build it, then tune it
Gather the real parts of a comb-finger MEMS accelerometer, then dial in the proof mass, spring, and air gap to see how frequency, quality factor, sensitivity, and noise respond.
PHASE 1 OF 2
Assemble the sensor cell
No parts gathered yet.
โ Sensor cell assembled!
Anchors hold the folded springs to the substrate, the springs suspend the proof mass, and fixed fingers interleave with it to sense every move capacitively.
PHASE 2 OF 2
Tune the sensor design
The mass, the spring, and the air gap underneath the mass set everything else. Adjust them and watch the readouts move.
Natural frequency
โ kHz
Quality factor
โ
Sensitivity
โ nm/g
TNEA (noise floor)
โ ยตg/โHz
CHALLENGE COMPLETE
๐ You designed a working accelerometer
+60 XP
ฯโ = โ(k/m) ยท Q = mฯโ/b ยท S = m/k ยท TNEA = โ(4kBTb)/m
The same mass and spring set both the frequency and the sensitivity โ that's why a stiffer spring always trades sensitivity for speed. The air gap sets the damping (b) through Couette flow, which is what actually controls the quality factor and the noise floor.