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Current time:0:00Total duration:8:23

Video transcript

you know we're going to try and create a new product using the products that we've taken apart we're going to look at the innovation process brainstorming and then try and solve some of the initial problems that we face in making these products work together so this is a little digital recorder I got at Radio Shack and you can see there's the hairdryer there and we've got a tap light right here and the tap lights just you know a battery-powered LED light and we got our zip ties and you can see the digital camera and the alarm clock and we're we're trying to find ways to make these work together and do something useful for us so we're going to take out our sketch pad and start drawing out different concepts that we might be able to make with these things so the tap light I like the dimensions of the tap light so I'm going to try that first we're going to use the the hair dryer has motors so we know the motors can blow the tap light or potentially move something so we're sketching a tap light with hairdryer motors on it that can blow it around and make it make it move and we maybe will use the body of the alarm clock to create a little bot that drives around we need some wheels for that and again we might be able to use the the hairdryer motors or maybe the DVD player motors so I'm interested in creating something with a personality that can move around something that is able to respond to its environment and I can use the products that we've already disassembled to to make something new hopefully maybe can take pictures and maybe record some sounds and play those sounds okay now that we have our objectives how do we make it work so what we're going to do is we're let's just isolate each one what to move around we can use the hair dryer motor and we know that moves and we could use two of them and maybe use them to blow air to move our device so or we could turn a wheel with them and to interact with the environment we need some sort of switch or sensor so we maybe could use the switches from the alarm clock so that if it hits a wall or something it can back up and turn around and we can use our camera and sound card to record images and sound but how do we control all of these things well we're going to need a microcontroller and we've got we've selected a microcontroller and we've got our camera and our sound card and our motors from our hairdryer and then of course we have our tap light and we probably could use the tap light as our body to put everything together in we need something to power all this we need batteries one of the first issues we're going to run into is that we think the motors run on 12 volts we know that the sound card runs on 9 volts because that's the kind of battery it needs and the camera takes 4.5 volts the microcontroller or Arduino takes 5 volts so everything's running on different voltages we have to find a way to control all of those voltages and what get everything to work together so we can do that with a motor controller the motor controller will provide different voltages for us to run on and allow us to run our our high current high voltage motors with our and control them with our low low power low current low voltage Arduino so that's why we need the motor controller and we go into more detail on that in the motor controller video so let's get started taking our hair dryer motor apart and our taking it out of the hair dryer should say and since that's going to be what we're using to move our crafts around we want to start to experiment with it and see how much power it's going to require and how much torque it's going to have in things like that alright so we're going to experiment with our motor and see what it what it's going to take to power we got our alligator clips connected and we're going to use a 1.5 volt double-a battery to see if we can make the motor turn and to kind of get a sense for how much air it will pull through it at 1.5 volts so we've got a little piece of plastic here to to test the motor so we're running it and we're holding the plastic up and you can see it's not moving the plastic at all so that's that's not going to work we're going to need more volts than that and we can increase the voltage by combining the cells in a battery holder and that allows us to wire the cells in series so we go from 1.5 volts to over 12 volts because those cells are new so let's see what impact that has on the motor okay so we're connecting our battery to our hair dryer motor and whoa you can see it's moving much more quickly now now it'll push the plastic completely out of the way and we're getting a fair amount of air coming out of it but I don't think we're going to use this method for moving our crafts because even though it's blowing a fair amount of air it only works really efficiently in one direction in the other direction it doesn't work as well because it's only meant to blow air in one direction out of the hair dryer okay so let's determine the actual specs for our motor so we know exactly what we can run it on and how much voltage it needs to do that we're going to need to remove the propeller and the outer housing around the motor so we're just going to trim that off with our hacksaw there and we're time lapsing this so you don't have to sit through all of it but in any case we're going to trim the the propeller off and then it's a really tough thing to get off because it's friction fitted on to this brass fitting on the end of the motor and so it's really hard they definitely did a good job of press fitting that on to the brass fitting so that it won't come off in as the hairdryer moves around so we're taking our nipper pliers here and we're just going to trim the rest of the propeller off so we can get to the motor and we'll move the at the end of it off there and then unscrew the last two screws and slide the ends off and then we'll take a look at our speck okay we've got our motor here let's flip it around and see if we can find the specifications on it and yeah there's some there's some printed text right here okay so we can type that printed text into the computer and determine what kind of motor this is and what the specifications are so it's always good to type in the actual name of what you're looking for when you type in your part list there so we've got a caisson a specification sheet this is actually a mabuki motor and we'll go through and we'll see if we can find it it's right there the 2073 model so our voltage is operating voltages between nine and 24 volts nominal voltage is around 20 with no load the motor will spin it's seventeen thousand two hundred rpm which is very fast at a current of 0.2 amps and we're always going to be operating under load so we'll always be pulling more than 0.2 amps the speed of the motor can you know at maximum efficiencies around fourteen thousand four hundred and twenty and then we've got a current at that speed of around one amp and that's under load and then the torque is nine point four nine Newton meters or 96.7 gram centimeters and the that's the twisting force that the motor can generate and so that's an important number to know does it does look like that's going to be enough to move our craft around since it's not going to be very heavy and then the motor can generate an output of fourteen point three watts so what's in what's the key number that we need to take out of this chart is the voltage we need to make sure that we're operating within the voltage envelope that the motor can run on and if we use our batteries together in in series like we did when we were testing it we can operate it around 12 volts which is between the nine and 24 volt range and should be fine for us to to run at now we're going to control the speed of the motor using our Arduino and our motor controller so the Arduino is going to send what's called pulse width modulation to the motor and that's gonna change the speed make the motor run much more slowly than it would if it was just running with straight current