Brake Angle Position Measurement

laser

https://www.youtube.com/watch?v=2b-BE5c-cg4&ab_channel=MTIInstruments%2CInc.

using the Hall effect

2 pole sn magnetic disk is fixed on actuator shaft

its position is detected by an ic sensor aligned to it with a small air gap between the magnet and the sensor

this is used to measure the angle position of a moving element by using a magnetic field instead of a physical brush or wiper

use a magnetically biased Hall effect integrated circuit ic that senses the rotary movement of the actuator shaft over a set operating range

no moving contact so wear is eliminated

each Hall effect sensor has a power supply and output terminal filter capacitor

the pedal circuit contains two independent Hall effect sensor ics with filter capacitors at each of the power supply terminals and at each of the output terminals. the filter capacitors enhance and improve the immunity to electrical noise

the rotation of the actuator shaft changes the magnet’s position relative to the ic and the resulting flux density changes. it is converted to a linear output.

inductive type

consists of a sensor and activator

the activator is made of 10 mild steel and a mounted pedal assembly

the sensor monitors the position of the activator as it moves across the sensor face

this is a three step process

1. it generates a magnetic field which penetrates the activator. this causes it to produce its own opposite field

2. the next coil stop generating its magnetic field and measures the activators induced field

3. the measurements are compared across the series of coils to calculate an absolute position of the activator

https://www.gillsc.com/products/position-sensors/1484-linear-position-sensor/

inductive type

using the principles of a wire loop induction and eddy currents

eddy current method is based on the principle of generating circular electrical currents in a conductive material. this is achieved by the use of a coil connected to an alternating current generator driving an alternating current generator driving an alternating magnetic field

the contactless inductive type accelerator pedal position sensor consists of a stator and a rotor