13th August: Day 1
This is my learning journey on electronic and simple robotics for a design technology curriculum which has an underlying philosophy of solving interesting and hopefully real problems in a sustainable way.
Here’s a video on making a simple car robot.
Great that he uses old materials to make the car.
Materials needed: Hot glue gun, motors, batteries – where to get motors, LED’s, switches, wires and batteries from?
Answer: catalog.miniscience.com (Motor’s, LED’s and Switches)
Batteries and wires: Don’t know.
1) Should I teach students how a motor works? I guess this depends on age. With Grade 8 could do it on a basic level. Nice video below.
Question for future: How to reverse the direction of the coil to make the car go back? – of course would only be appropriate for a remote controlled car. Maybe the answer to this lies in changing the wires round??? I guess it does because that would reverse the magnetic field thus changing the direction of the field lines and turning the coil in the opposite direction???
2) How to put a switch on?
Next Steps: Need to trial this and video it. Gain all necessary materials within 2 weeks by the 27th August.
15th August: Day 3
Like the idea (by Mark Shillitoe) of starting with a Bristlebot
25th August: Bought equipment
I bought a huge science kit of motors, batteries, switches, LED’s, propellers, wiring, etc. today. Just need to pick it all up from the UK now….
1st September: Putting together the Dragster and the Mental Detector Robot
CD Dragster which runs on a simple motor and axle system.
Things I learnt whilst putting it together:
1) I think with a lot of trial and error I could now make a wired remote that controls the forward and backward motion of a motor. It will probably either require some soldering and ingenuity or it would be much easier for me to order some slide switches from the TTS.
2) Interesting to learn how metal detection works on a basic level. The metal detector contains a transmitter coil with an alternating current (change in current direction lots of times) passing through the coil. The alternating current turns the coil into an electromagnet which creates a changing magnetic field. When the field interacts with a metallic object, it induces a current in the object which results in the object creating its own magnetic field. This magnetic field induces a current in the receiver coil of the metal detector which then lights up an LED or makes a sound.
Next Steps: Order the slide switches to the UK. Look into how to get the wheels to change direction.
4th September: Arduino Project 1 – LED Flash
Just copied my first code which was a simple LED Flash set to flash for one second and then turn off for one second repeatedly. It only requires a breadboard, an LED, wiring and a resistor. The Digital Pin 10 on the Arduino, outputs 5V DC at 40mA and the LED requires 2V at a standard current of 20mA. Hence by Ohm’s Law (Resistance=Change in Voltage/Current Needed) I needed a (5V-2V)/0.02 = 150Ω resistor. Since the lowest resistor I have is a 220Ω, I just used that instead which therefore supplied a 13mA current to the LED. It seemed to work fine but I wonder what would be the lowest current it would need to flash?
Anyhow, great to finally get using the Arduino and gaining a very basic understanding of the coding language.
5th September: Arduino Project 2 – Traffic Lights
This would be great with remote controlled cars!
10th October: Arduino Project 3 – Traffic Lights with Pedestrian Crossing
Even better with remote controlled cars!!!!
17th November: Arduino Project 4 – LED Chaser (with Potentiometer)