Metal Detector

Learning about capacitance and electromagnetic induction from A-Level helped me understand the underlying principles which allow metal detectors to work, but I was intrigued to know more about the function of the additional subsystems that make up the detector circuit. During this, I gained deeper understanding about comparison circuits and amplifier circuits.

1. The fundamentals and experiments

Electromagnetism is the basis of metal detectors. Except some theories that I learnt in A2 physics course(which I took ahead), such as magnetic flux, Lenz’s Law and Faraday’s law of electromagnetic induction, I also learnt about oscillating circuit additionally.

I could review physics knowledge, including electricity and magnetism, and deepen my understanding of electricity and magnetism in a visualized way by conducting experiments. Recognizing basic electronic components such as resistance, capacitor and inductance, was another target. During this period, I also learned the operation of the oscilloscope, which I hadn’t met before.

2. Basic electronic design

In this part, I learnt the fundamentals of electronic magnetic induction, and how to read schematic diagrams. I also learnt how to use bread board, complete the electro-magnetic circuit design based on the bread board version myself. Moreover, I learnt how to measure and analyze the circuit signal after completing the circuit.

3. Prototype design and verification

In this phase, I put the theory into engineering practice, and got a new skill - soldering. Based on my previous circuit on bread board, I implement the design on the universal board to make it more general. After completing metal detector prototype, I conducted relevant tests.

4.Product design

This phase is about optimizing the design, by evaluating the whole process from ideation to production.

Based on the test result from the last phase, I was able to analyze the circuit design, find out the shortages, and optimize it. Moreover, I learnt to use CAD to deploy their circuit design to PCB, and I delivered the design to the manufacturers to finish the whole process from design to production.