Lab 7 — Straight Driving, Accurate Turns & Localization

Duration90 minutes

Depends onLab 6

MilestoneRepeatable straight run + controlled turn + localization

StatusOutline — to be written

Practical focus

Use encoder and IMU feedback to correct the drift problem from Lab 1; drive a fixed distance; perform 90° turns; estimate position and heading between known points.

This is the payoff lab

Everything since Week 1 has been building the measurement and control tools needed to solve the problem the students met on day one. Say that out loud — it is the moment the course structure becomes visible to them.

Objectives

1. Drive a straight line using feedback, and beat your Lab 1 drift figure.
2. Execute a repeatable 90° turn.
3. Drive a commanded distance and stop accurately.
4. Estimate position and heading by dead reckoning between two known points.

Procedure outline

TODO — expand.

1. Close a heading loop using the IMU, or a wheel-speed-matching loop using encoders — or both.
2. Repeat the exact Lab 1 drift test. Same 4 m track, same 5 runs, same measurement.

3. Compare directly against the Lab 1 numbers.

   	Lab 1 (open loop)	Lab 7 (closed loop)
   Mean drift over 4 m
   Spread across 5 runs

4. Calibrate a 90° turn. Measure the actual angle; correct; repeat until consistent.

5. Dead-reckon between two marked points and measure the final position error.

Dead reckoning accumulates error

Every small heading error integrates into a growing position error. Measure how far off the estimate is after 4 m, then after 8 m. The growth is the point — it is why Labs 9 and 10 keep an absolute reference in the loop.

Deliverable

Repeatable straight run + controlled turn + simple localization, reported against your Lab 1 baseline.