Solidworks P2

If we were able to progress further on our coding/ design process, here is what the projected device would look like.

The piece attached above is an IR sensor which would give the device some autonomous capabilities. Instead of someone controlling the device, an IR sensor would allow the device to act on its own. If someone were to walk near the IR sensor, it would trigger the IR sensor which would then tell the servo motor to go and they would then be sprayed with silly string.
A second servo motor could also be attached to the bottom to give the silly string shooter a 360 degree field of vision.

Solidworks

Below is a photo taken from our assembly of the project. Although it looks very rudimentary, it fulfills the proper mechanical requirements to match our prototype. 

It consists of the various parts that we have used in making the device. (cardboard platform, silly string can/ cap, wooden block, and the servo motor) Using solidworks allowed us to make any changes we wanted to make without having to physical change the device. 

 

Our take-aways and what we learned from this project

One thing we learned from this project is just how important troubleshooting skills and improvisation play a role in transforming a design into reality.  Our initial idea was not as simple to build and assemble as we thought it would be.  On paper our project with the silly string shooter with an IR sensor seemed fairly simple and straightforward based on similar designs we saw on the internet.  It took some creativity to modify various parts to work properly. One example where we used a coat hanger that originally went inside the silly string cap which was supposed to rotate 360 degrees.  We found this didn't work well or reliably so we got rid of the cap and mounted the servo on a wooden block which sweeps back and forth rather than rotating completely around.  There were other obstacles we ran into with the coding we had some success using a potentiometer to activate the servo but we wanted the more polished design of the IR sensor without have to manually activate the servo motor.  

Overall we didn't have any major things to do differently (other than order parts from Dr. Sullivan early so we didn't have to pay for them ourselves).  We took from this that problem-solving and troubleshooting skills are fundamental to making any design project a success.  Undoubtedly these skills will be improved with more practice and hands-on work with Arduino and coding.

The crude hanger that was cut and bent previously to act as the lever on the servo motor needed to be redone.  The following shows the new lever created which is straighter, more sturdy, and now reinforced by electrical tape.  This new lever should provide enough strength to push down on the silly string shooter.

The following shows the preliminary silly string setup being reinforced by the wooden block and held secure with electrical tape.

For the TeamDragon meeting this weekend we did some troubleshooting and determined the last Arduino board was responsible for our servo motor not functioning and not the motor itself or the power source.  We cut a wooden block to the right height to enable the servo to hit the silly string shooter each time as well as to stabilize the servo motor.vAfter examination of the hanger wire we used last time, we will most likely need to cut another piece which is straighter when horizontal.

We were able to get rudimentary motion using a potentiometer but the goal will be to use the IR sensor so that the silly string shoots as a result of detected motion rather than manually turning the potentiometer.  We found a couple sketches online which we can use as templates for the coding we will need to get the desired interaction between IR sensor, servo motor, and silly string shooter.  

For the upcoming week we will also work on cutting another wooden piece which will serve as the platform of the silly string shooter the servo motor.  

During our meeting this week we received the IR sensor and motor shield that were ordered last week so in  the lab attempted to test the functionality of our stepper motor using the example sweep code.  We tried connecting the servo directly to the board into ground, 5V, and the signal pin but we got no response.  After further troubleshooting we found that the problem was most likely with the specific board we were using but we ran out of time before we could try running it with another one.

We also were able to bend and cut a piece of coat hanger wire that seems to provide enough strength to push the button down on the silly string shooter.  Obviously we will need to get the servo motor operational before we know if the hanger wire will perform reliably.  

Our goals for meeting this Sunday will be to make sure the servo works and then continue fine-tuning the code which will allow the IR sensor to trigger the servo motor with little delay once triggered.  We will also cut a block (maybe wooden) to rest behind the silly string shooter for the servo to rest on.  Additionally we will use another wooden block underneath the apparatus for stability and the final step will be cutting out a stuffed animal from which the silly string will be shot from but which doesn't impede the IR sensor.