Brenn Magnetic Motor

  
MOTOR EXPERIMENT

How to Make a Simple ELECTRIC Motor

Energy comes in many forms. Electric energy can be converted into useful work, or mechanical energy, by machines called electric motors. Electric motors work due to electromagnetic interactions: the interaction of current (the flow of electrons) and a magnetic field.

Materials

AA battery
Insulated Magnetic wire
Metal plate holder
Electrical tape
Side cutter/fliers
Small circular magnet

Procedure

Starting in the center of the wire, wrap the wire tightly and neatly around the pipe 5 times.

Remove turned coil into the pipe and centered secure.

Wrap each loose end of the wire around the coil a 2 times to hold it together, then point the wires away from the loop

Remove the isolator coil in each side of the end

Use electrical tape to secure the metal plate holder upright next to the terminals of each battery so that the side of each needle touches one terminal of the battery.Your coil should be hanging above the battery.

Lay the AA battery with the metal plate holder on a flat surface.and secure with electrical tape on the ground

Place the magnet to the battery so that it is centered underneath the coil.

Give your coil a spin.

How to Make a Simple HOMOPOLAR Motor

The first homopolar motor was demonstrated by Michael Faraday in 1821.

To make a simple motor that doubles as a work of art you will need three things

– a battery, magnet, and wire-

Energy from the battery travels in one direction (DC- direct current) from one end of the battery, to the other end. Copper wire, which conducts electricity, is made into a shape that connects the two ends of the battery, creating a continuous flow of electricity. The current travels through the copper wire back to the battery to complete the circuit.

The magnets in this experiment also have a positive end and a negative end creating a magnetic force that moves up towards the battery. This electromagnetic opposing force causes an outward motion, forcing the wire to spin in a circular motion. Here is a picture from MAGCRAFT illustrating the different forces.

Materials

AA battery
Insulated Magnetic wire
Side cutter/fliers
Small circular magnet

Procedure

Take your copper wire and fold it in half and squeeze the bend together with your pliers,turn around the pipe 10 times.

Remove turned coil into the pipe

Remove the isr coil in each side of the end

Place the negative side of the AA battery on top of a couple magnets. If you place a larger magnet on the bottom and stick with with double sided tape to the counter, this will help prevent the battery from falling over. Another trick that we found to be useful is to use double sided tape to attach two washers to the positive side of the battery, this will help the wire stay on.

Results

The motor will continue to spin when pushed in the right direction. The motor will not spin when the initial push is in the opposite direction.

Why?

The metal plate and wire created a closed loop circuit that can carry current. Current flows from the negative terminal of the battery, through the circuit, and to the positive terminal of the battery. Current in a closed loop also creates its own magnetic field, which you can determine by the “Right Hand Rule.” Making a “thumbs up” sign with your right hand, the thumb points in the direction of the current, and the curve of the fingers show which way the magnetic field is oriented.

In our case, current travels through the coil you created, which is called the armature of the motor. This current induces a magnetic field in the coil, which helps explain why the coil spins.

Magnets have two poles, north and south. North-south interactions stick together, and north-north and south-south interactions repel each other. Because the magnetic field created by the current in the wire is not perpendicular to the magnet taped to the battery, at least some part of the wire’s magnetic field will repel and cause the coil to continue to spin.

So why did we need to remove the insulation from only one side of each wire? We need a way to periodically break the circuit so that it pulses on and off in time with the rotation of the coil. Otherwise, the copper coil’s magnetic field would align with the magnet’s magnetic field and stop moving because both fields would attract each other. The way we set up our engine makes it so that whenever current is moving through the coil (giving it a magnetic field), the coil is in a good position to be repelled by the stationary magnet’s magnetic field. Whenever the coil isn’t being actively repelled (during those split second intervals where the circuit is switched off), momentum carries it around until it’s in the right position to complete the circuit, induce a new magnetic field, and be repelled by the stationary magnet again.

Once moving, the coil can continue to spin until the battery is dead. The reason that the magnet only spins in one direction is because spinning in the wrong direction will not cause the magnetic fields to repel each other, but attract.

WATCH VIDEO TUTORIAL

Using ultrasonic sound wave to be tested on an oscilloscope

What is Oscilloscope?

An oscilloscope is a machine that shows the wave shape of an electrical signal. When connected to a ultrasonic module they can show the wave signal.

The Arduino ultrasonic module includes transmitters, a receiver and control circuit. This distance sensor works by sending out an ultrasonic wave from the trigger terminal and detecting whether there is a pulse signal back through the echo. If there is a returning pulse signal, it is measured, and the length of time the pulse remains at a peak corresponds to the distance an object is from the sensor.

The longer the returning pulse is, the further the object is away. A short pulse of at least 10 micro sec is supplied to the trigger input to start the ranging, and the module sends out an 8 cycle burst of ultrasound at 40kilohurts, and the echo is raised.

Here is how to calibrate an Oscilloscope:

With the use of Probe
put the ground then the test calibration and setup the settings.

Oscilloscopes principally measure voltage and time. Measuring another physical property such as temperature, pressure, flow, velocity, or displacement on an oscilloscope requires use of a transducer or sensor to convert the measured quantity into voltage. Using the oscilloscope's function you can scale the input voltages into units that match the transducer's input.

Procedure

The 5V DC supply was connected to the VCC pin on the sensor.

The function output was connected to the Trig pin.

All the grounds were connected together

Chanel2 of the oscilloscope was connected to measure the input pulse (Trig).

Chanel4 of the oscilloscope was connected to the Echo pin to measure the returning pulse, if any.

Without any object positioned in front of the sensor, the following was obtained on the screen of the oscilloscope:

The function output was set to produce a low frequency pulse.

The distance was measured, and the waveforms displayed on the oscilloscope were recorded. The waveforms displayed were used to calculate the actual distance the sensor measured from the object.

An object was then positioned in front of the sensor:

And the oscilloscope displayed the following. Here the peak of the returning signal was of a duration of roughly 1.5milli second, the distance measured with the calculated distance of approximately 25cm

The object was then moved closer to and further from the sensor. One such position

The angle of the object to the sensor was also varied to test the sensor’s ability in detecting objects that aren’t straight in front of it.

Here the peak of the returning signal was of a duration of roughly 0.333milli second, and thereby measured a distance of approximately 5.5cm when calculated, which is close to the distance.

The angle of the object to the sensor was also varied to test the sensor’s ability in detecting objects that aren’t straight in front of it. One such position

The waveform displayed on CH4 of the oscilloscope indicates that the object was approximately 25cm from the sensor, thereby showing that the sensor can quite accurately detect the distance it is from an object that is an acute angle. This maximum angle at which the sensor detected the object during testing was approximately 20°.

One negative about this sensor is that it’s blind for the first 2cm, but more importantly, careful mounting must be adhered to, as if it’s positioned too high it won’t detect other robots and if it’s positioned too far back on the robot, it will detect itself and presume it’s an opposition robot