Inductive proximity sensors consist of a coil, oscillator, trigger circuit, and output, operating on the principle of inductance to detect metallic objects through changes in electric fields. They are used in various applications, including robotic hands and wind turbines, offering advantages like high accuracy and adaptability to harsh conditions. However, their limitations include the inability to detect non-metallic targets and a potentially limited operating range.

1. Inductive
Proximity
sensors
BY
AHMED MAHMOUD AHMED

2. Components
 An inductive proximity sensor has four elements:
 Coil
 Oscillator
 creates a radio frequency field that is shaped and defined by the coil and core
 Trigger circuit
 rectifies the AC sine wave signal to DC
 Output
 It changes according to the presence and absence of the target

3. Basic operation
 Proximity sensors are one type of pre-touch sensors.
 Inductive proximity sensors operate under the electrical principle
of inductance where a fluctuating current, which by definition has
a magnetic component, induces an electromotive force (emf) in a
target object.

4. Basic operation
 When a conducting object is found in sensor’s domain it reduces
the induced current in the electrodes.
 This change in the electric field is detected by the sensors.
 Specialized algorithms process the data and instruct the rest of the
machine to take appropriate action

5. Example from Intel
Robotic hand
 The researchers have incorporated the sensors into a robotic
hand as well, allowing mechanical fingers to adjust to the
size and shape of an object that they encounter.
 The goal, is to improve the ability of robots to grasp objects
in unstructured human environments.

6. The video

7. Wind turbines
 Wind Turbines uses proximity sensors
to determine the best direction to
which it should be adjusted to get
maximum wind possible

8. Advantages
 They are very accurate compared to other technologies
 Have high switching rate
 Can work in harsh environmental condition

9. Minesweeper
 A robot to sweep over an object and collect EF information from it.
 The algorithm then compares, in near real time, this data to a series of
prerecorded signals that describe various shapes, sizes, and orientations
of the object.
 When the algorithm finds a reasonably certain match, it adjusts the
robotic fingers so that they can grasp the object.

10. Disadvantages
 It can detect only metallic targets
 Operating range may be limited