2 Pin fans - 1 pin for power and 1 for ground. The fan is either on and off.
3 Pin fans. Three pin fans have 1 pin for power, 1 for ground and a feedback tacho pin. The feedback can be used to calculate the speed of which the fan is spinning.
4 pin fans. These fans have the same features as the 3 pin fans and a 4th pin used for PWM, allowing you to control the speed of which it spins.
In this project I use PWM to control the speed of which a 3 pin fan spins. Ive used the tacho pin to work out if the fan gets jammed and an alarm circuit sounds a siren if its not turning when it should be.
The fan is turned on and off automatically using a temperature sensing subsystem. A variable resistor has been used to allow the user to control the temperature of which it turns on.
The entire circuit can be turned on and off with a SR Latch.
Ive used an arduino nano to work out when the fan is turning. Using the PulseIn() command the arduino returns the width of the pulse in milliseconds. In the future I plan to add some 7 segment displays its frequency.
Using a audio amplifier kit from kitronik, I designed my own speaker. The kit I selected came with the option to power the speaker from batteries or USB.
I used a laser cutter to cut all the acrylic parts. The clear curved side panel allows users to look into the inner workings or the dock. The side panel was curved by heating it up in a heat press before forcing it into a custom made MDF mould.
I added fancy colour changing LEDs to make the dock stand out. These LEDs run off of a separate circuit so you can use the dock without having to have them on, when on they flash different colours, illuminating a room and creating a fun party vibe.
Ever wanted to control your lighting, or any other appliance, from your phone?
I built a bluetooth operated socket to switch a desk light on and off
remotely. I used a arduino compatible microcontroller based on the
arduino nano, HC-06 bluetooth module to connect to a phone and a relay
board to switch on and off the 230v supply.
To power the microcontroller I used the 5v transformer from a phone charger.
I used the app “ArduDroid By TechBitar” to send messages to the
microcontrollers Serial Port. By sending different commands you can turn
on and off each relay separately or them both at once.
A relay acts like an electronic switch. It has two outputs, normally
closed and normally open. When it receives a control signal it connects
the input of the relay to the normally closed output. Otherwise the
input signal is sent top the normally open output.
The Relay Board, Mircocontroller and Bluetooth module.
Once the circuit had been assembled and tested I fitted it into a 2 gang pattress box. I connected one of the relay's outputs to a one gang socket.
Student Robotics is a
volunteer based organisation that runs an annual free-to-enter robotics
competition for 16- to 18-year-olds. Competitors design, build, program and
develop fully autonomous robots to compete in non-contact challenges.
This years game saw us develop robots that
used a web camera to scan QR codes (known as tokens) to navigate the arena and
rotate cubes such that the team colour faced upwards. Cubes had 4 colour faces,
belonging to the 4 teams that took part, and 2 neutral faces. Different
cubes had a different order of coloured faces..
I lead our team, from Brockenhurst College and
was in charge of design and development, using my expertise to construct the
robot and collaborate with the programming team.
Videos of the competition can be seen here and here.
Our main tactic was to flip the boxes using a giant "whisk",
allowing us to consistently come first or second in our games.
The team made it to the final where we came across an unpredictable error - the
Student Robotics staff provided each team with a memory stick at the start of
each round, this would tell the robot its team colour. During the final the
memory stick came loose and jammed our box turning mechanism, halting the
robots process.
Ive always been interesed in how things work and assembly language gives you a good idea into how a computer uses differents registers to complete tasks.
I wrote a small assembly language program that controls a fan cooling system. You can adjust the temperature the fan turns on and off at using a number of differnt buttons. I used a PIC mircocontroller to run the code. The output fan is simulated by a LED.
