1. Sensors for industrial mobile Robots Incremental sensors
Need more/better pictures

2. Magnetic encoders More reliable Less expensive
Less accurate than optical
Less resolution (BUT can be used interpolators)

3. Magnetic encoders
To sense direction

4. Interpolation to multiply resolution
A considerably higher resolution of angle φ is possible if we apply the interpolation process described in Figure.
The graphic representation of sin(φ) versus cos(φ) produces a circle as a special Lissajous figure in which angle φ is immediately recognizable. The interpolator now compares the current angle value φ0  with predefined discrete angle positions and as a result generates the matching quadrature signals A and B.

5. A complete scheme with interpolator

6. Gyroscope – fiber optic

7. Gyroscope vibrating
Coriolis force:

8. Example: Use of encoders + gyro
Steering encoder
gyro
Traction encoder
… my first AGV prototype

9. The discrete form of the inertial-odometric navigation equations is as follows:
Use of encoders + gyro

10. Use of encoders + gyro

11. We have two separate estimations of the attitude so we have to combine them in a suitable (possibly optimum) way.
To achieve this the two attitude increments are combined by a data-fusion algorithm in order to estimate the best guess for the two.
The procedure is as follows:
the two increments are estimated,
the type of manoeuvre the vehicle is actually undergoing is estimated using the inertial-odometric data (table 2),
the accuracy ratio of the output of the two navigation systems is estimated using table 1
the data fusion algorithm combines the two increments
the output of the data-fusion algorithm is added to δk
Use of encoders + gyro

12. Step 1 – attitude increments est.

13. Step 2 – manoeuvre estimation

14. Bayes Fusion (optimum in case of Gaussian white noise)
Step 3 – data fusion

15. Step 4 – accuracy ratio estimation
the accuracy ratio of the output of the two navigation systems is estimated using table 1
Step 4 – accuracy ratio estimation

16. Step 5 – add the increment
the output of the data-fusion algorithm is added to δk:
Step 5 – add the increment