Electronics
Won a $2500 Keysight oscilloscope on EEVBlog
As any professional or hobbyist involved in electronics would know, oscilloscope is an indispensable tool when it comes to building prototype circuits.
I refrained from buying one for myself due to their high cost. My wait was finally finished when I won a 2500USD machine on EEVBlog - Keysight giveaway. It was an honor to see Dave Jones appreciate my work and find me worthy of receiving this machine.
Link for winners announcement on YouTube: Click here
Link for my EEVBlog forum post: Click here
Control/data acquisition electronics for Motor Propeller system for data acquisition
I designed the electronics system and wrote the code for the Arduino microcontroller.
This system has multiple op-amp stages for force measurement. The circuit also has RC filters to smooth out the current measurement which as multiple spikes due to the rapid switching of poles in a BLDC motor.
Details about the circuitry can be found in the report attached, by clicking here
Overcurrent protection
I designed this circuit to cut off the power supply to any circuit if the current exceeds a certain threshold. The gray resistor is the main shut which measures the current going to the circuit. The IC is the operational amplifier which amplifies the current value measured by the shunt. The blue box is the main relay which disconnects the power supply when an over current is detected. The two transistors in the lower right corner make the RS FlipFlop which resets when op-amp indicates the overcurrent and sets when the button in the middle is pressed.
PCB circuit design on EasyEDA
I learnt to design a PCB from scratch on EasyEDA. EasyEDA is a free software where one can design a circuit, add the package and create routing for the PCB.
PCB etching
I have mastered the art of PCB etching on a copper board. The board that I have shown here is the same as the EasyEDA design that I have shown above.
Power electronics for coil-gun
The coil gun had four stages of coils for launching the projectile. For controlling these four stages of coils, there are four power transistors. These power transistors are operated by four pairs of Light Emitting Diodes and Light Dependent Resistors.
Together, they can accelerate the projectile to decent speed. The
Torque transmitter
I made this device so that one can know the torque that is being transmitted through a shaft. The device has a torsional spring and it a potentiometer. The torque in the shaft is transmitted via the spring, As the torque on the shaft increases, the twist in the spring also increases and this twist is measured with the potentiometer.
The reading noted by the potentiometer is converted into a PWM signal with NE555 timer IC and is transmitted with a RF transmitter.
The circuit I created to analyze the power consumption of a BLDC motor. (Resistors are shunts, RC filter for noisy shunt voltage, OP amps)
Circuit for my two generation of coil guns.
Click here for document link
Video 1 Video 2
The circuitry I designed to run two motors in my wind tunnel model
Link to some pictures of projects
A salvaged high current transformer. Kept in a corner in the hope that I will be able to do something fun with it, someday.