Rube Goldberg #2

Rube Goldberg #2

At first, we will heat the temp sensor. The rise in voltage from the heat sensor will allow the counter to begin counting. Once the counter reaches 9, it goes through a series of logic gates that will produce an output voltage, only on binary 9. This will cause the motor to spin where it will knock down a set of dominoes. At the end of the domino train is Tipsy Tim, just waiting for someone to push him into his cab so that he can get home safely. Giraffes don't drink responsibly.

Here is a picture of one of our original designs:

This was one of our first set up designs, the main difference is that the
 relay sent its signal to the counter. We did not go with this plan because we
could not get the gates to do exactly what we wanted them to do.

We had many troubles when building this circuit. The first problem that we had was that the driver was outputting small voltages to segments that were off instead of 0V. This caused the gates to stay on when they're not supposed to be. Our next biggest problem involved our creative brains being temporarily shut off. We had few ideas for what materials to use because we are limited to what's inside of our dorms and the dollar store. The temperature sensor was very fussy and was at times unreliable in getting the circuit to run. We had a plan to use the temp sensor to trigger the counter but the pulse signal from the counter was too short to turn on the motor, so we rearranged the order of operations.

Here are some pictures of the construction and testing of the final circuit:

Here we are testing to see if the pressure sensor could work in this configuration
given that the weight of the object would not be very heavy. As you can see, Tipsy Tim
wanted to help us out.

Tipsy Tim also wanted to help us build the arm for the DC motor.

He also demanded that he build the domino track since he would
be the one would was getting hit by it. But Tipsy Tim didn't get his
name for no reason and after the first handful of attempts, allowed us to
build it for him.

In the end we set up our Rube Goldberg project where the temperature sensor would be amplified by a non-inverting amplifier, which would trigger the relay. The relay would start the DC motor once tripped. The motor had an arm attached to it that would knock down the dominoes, creating a ripple effect through the set up design. The dominoes near the end would branch off into two parts one would go back to the breadboard where the last domino would fall onto a pressure sensor, the other would knock Tipsy Tim off of the table and into a cardboard box below (we were on a budget). Once the pressure sensor was engaged the circuit we built in the previous week's class was turned on which caused the LED display to start counting between 0 and 9. An LED was attached through logic gates to only light up when the displayed number was 9.

Here are some videos of the different stages/ideas we were looking at throughout the week:

This is showing how the counter will work with the pressure sensor attached 

to the 555 chip.

Here we were working with logic gates to have an output signal only on a specific 

number. The original plan was to have the motor be on for the period of time but

we ended up going a different route with it.

This is us making sure that falling dominoes would in fact knock over Tipsy Tim

This is a video of us trying to get the dominoes to knock over Tipsy Tim as

well as get the dominoes to activate the counter by landing on the pressure sensor.

Our final project did in fact work, though unless you counted the time it took for the temp sensor to heat up enough, the final design did not last the full 30 seconds. When we showed the class our project everything went fine once the temperature sensor outputted enough voltage to flip the relay, the only thing that did not go the way we wanted it to was Tipsy Tim missed his box when he fell from the table.

Here is the final, complete Rube Goldberg project.