Elevators, Switches, and Relays, Oh My!

For so long it seemed like this summer would never end, yet now that I only have one week left at my internship it feels like time has absolutely flown by. Over the last two weeks I have learned a lot more about the workings of the company, and have even learned how to do some things that few other people at the company know how to do, making feel as though I am really an integral part of the team. And for some of those things I am actually working on writing guides to teach other members of the company so they will retain the information once I leave, which is bittersweet. I like the idea that my having been there will help things for the long term, however it also reminds me that I need to finish the guides because I will soon be leaving.


As my internship is drawing to a close, I feel like I am just starting to get more responsibility with my tasks, which is exciting yet I know it is fleeting. Three of the more hands on projects I worked on in the last weeks are:

  1. Changing the relays out of the back of the Thumper, where I was in charge of taking apart pieces of the internal wiring and replacing parts, before putting things back together. It was really neat to feel like I was using my hands to actually affect change, instead of just working through computer systems. Most of the relay switches must be changed because the internal wiring gets melted, a side effect of using the relays far out of their specs. However, one of them actually had an entire side blown out! Which I thought was crazy cool.
  2. Changing the wiring inside a manual, 12 terminal switch in the control center of the Thumper. Which involved multiple internet searches, deciphering the line diagram that came with the Thumper, and an email chain with the manufacturer. I finally managed to figure out that when they built the Thumper, someone modified an external jumper on the switch, changing how everything was connected. It also very greatly changed what the manufacturer was telling me about the functions of the switch, and led to a day of trying to figure whether the line diagram or the manufacturer was correct about the switch configuration. When I finally figured it out it was such a satisfying feeling, especially because I was completely at a loss when I started the project.                                                                                                                                                              
  3. Taking two uPMU’s home with me to set up for Thumper testing, one for my apartment in Berkeley and one at my “home home” in Stockton (in a giant and very heavy suitcase!). These will help record Thumper data even after I leave the company! Which is exciting to think that I could help further this research even after I stop working at PSL.


Probably one of the most exciting things from the last week was the data I collected from the uPMU in my Berkeley apartment. While examining the data I realized that every so often there would be a ~2 Volt dip in the voltage measurement, which I later determined to be caused by the elevator! It may have been a trivial discovery but I definitely felt like a detective. I told my bosses about it and one of them told me I should dig deeper and see if I could find out other things from the data, and possibly turn it into a research paper, which I am extremely excited about. By collecting more data I discovered that the elevator only makes visible voltage dips when it is traveling up, and not down, and I am currently trying to pinpoint the number of seconds that it takes to travel to each floor. Thus, from the data directly I might be able to tell where exactly people travel when they come into the apartment building. I never thought I would be this excited about elevator rides, and it has been really cool to have my own project to work on.

 (the elevator voltage dip!) 

As for the uPMU that we put in Stockton, it has shown far less exciting data than the one in Berkeley. No data, to be exact. It seems to be having problems connecting, and we do not know if we will be able to get it up and running for long periods of time/at all. Which is slightly disappointing, however understandable as with any testing, things do go wrong.


Another project I have been working on wrapped up last week, which was designing a plastic frame to go in the Thumper and make it more presentable to people who visit/potential companies that might rent it out. In order to finish it however, I got to go on an excursion to San Leandro, which was a nice change from the office, and I got to see a laser cutter in action. (Fun fact: on my lunch break I walked a mile to get a burrito!)

(laser cutting!) 


Extra Extra:

I have learned that I can read while I commute, and have finished many books this way in the last few weeks. I have also learned that reading while walking is not as difficult as it sounds.

I realized that some math I had figured out near the beginning of my internship was incorrect, and spent most of a day fixing my calculations, along with editing some graphs that I drew for those calculations. But now the math seems so much more elegant and I am kicking myself for not seeing what was wrong before.

This past week I have also started working on a marketing questionnaire for the Thumper, in order to eventually allow the public to rent it!

We also had an ice cream sundae bar to celebrate birthdays.