Chris Week 12

Week 12

Chris Ruby's Individual Rube Goldberg Setup

    1. Provide the computer drawing for your individual RG setup.

       2.  Explain your setup.

         

             My setup all starts with a photosensor. While this sensor is in its cardboard holder that I made for it, it has a resistance value of about 4 to 5 kilo ohms. Once the light from Kevin's circuit hits it, the resistance value drops to about 300 ohms, allowing a stronger current to run through it. This strong current then powers my 555 timer, which starts up my digital display part of the circuit. This circuit is set up very similar to our circuit from earlier this semester. The only difference is that I am using the photosensor instead of the force sensor to start it, and at the end of the circuit, I have an AND gate that will ultimately turn on a motor. 

          To power the motor, I will use an opamp that will amplify the signal from the AND gate, giving the motor enough current to pull or push whatever I decide to use to trigger the next groups circuit. 

        3.  Provide photos of the circuit and setup.

    This photo shows how my photosensor is poking through a piece of cardboard, shielding it from most of the ambient lighting.

Here is a picture of my entire circuit, minus what the motor will be hooked up to.

This is a closer look at the digital display part of the circuit, with the AND gate, LED, and motor at the bottom.

    4.  Provide at least 2 videos of your setup in action, one being a failed attempt.

Here is a video showing how the light activates the rest of my circuit. There is nothing attached to the motor just yet, but there will be soon. Also, the motor doesn't actually spin in this video. There is something wrong in my configuration of the opamp, so the motor is not receiving the voltage required to turn on. When the LED flashes on is when the motor should also be turning on. 

Here is a video of the circuit with the motor working(briefly)!

    5.  What failures did you have? How did you overcome them?

           The biggest failures originally came from trying to start my circuit. I had planned a voltage divider circuit with the photosensor to activate a relay to then power the digital display, but I ran into trouble. I tried using an opamp there to provide more current to the relay, but that didn't work(or I messed it up).  Once I decided to try something else, I came up with the start of the circuit as shown in this blog, where I use the resistance of the photosensor to start/stop the digital display, and that works great. 
          After I figured out the beginning of the circuit, I had to figure out how to end it. I know I need to use a motor to do so, but I am still struggling to figure out how to power it. The AND gate puts out 5 V when the display hits 9, but the current is extremely small. To counter this, I tried to put an opamp after the AND gate, to attempt to provide more current to the motor. Again, either I messed up the setup of the opamp, or it doesn't work, but I could not get the motor to power on. I am still looking for a solution to overcome this last(for now) problem with my circuit.