Month: November 2019

Jason Huang

Accomplishments:

• Improvement of integrating Emily’s 3D data into my code
  
  Upcoming Work

Will continue working with 3D data, and hopefully making the 3D facial detection a lot better at detecting fake faces.

Schedule

Going to work during Thanksgiving to continue fine-tuning the code.

 

Emily

Finally fixed the pi/camera issue, so was able to get more data to Jason finally! Also fixed the picture taking script so that the camera had some time to settle before taking the person’s picture. Other work this week included taking a trip to Home Depot with the gang and buying a door and deadbolt, so I’ve been fine tuning the servos to that specific deadbolt. Next week I’ll be working with Jason to write some scripts to integrate all the pieces of code we’ve written so that things can be called sequentially following the order of our intended control flow.

Joe

I spent a lot of time in the lab this week. The first thing that I was able to accomplish was to increase the switching speed back to 100khz. I realized that the physical distance between the two mosfets was causing the gate signal to be slightly offset, resulting in some oscillations in the output. I moved the both right next to each other on the breadboard and it was better. I also attached some heat sinks to the mosfets just in case. On the actual power transfer side, I am looking into changing around the topology. (parallel-parallel vs series-series, etc). Something very strange that I noticed that the function generator was able to have a much greater efficiency in power transfer than the switching circuit I was using. This is leading me to suspect that there is something in the internal impedance of the function generator that is helping transfer more power, or that there is maybe some kind of signal noise that is reducing the efficiency for the switching circuit. If I can figure out how to get similar efficiency as the function generator on my power circuit, I should be able to send more than enough power, it is just a matter of figuring out why this is the case. I have read many papers on improving the efficiency of inductive power transfer, and I believe that I am hitting most of the important aspects. I strongly suspect that it may be a small issue that is causing low efficiency. I obtained several large capacitors and a voltage regulator so that shouldn’t be an issue once the power can be transferred.

Team

Went to Home Depot and bought a door, door handle, and deadbolt!

Jason Huang

Accomplishments:

• Started integrating Emily’s 3D data into my code
• Still hoping to fine-tune some of the other parts of my code; can partially detect 3D faces, not 100% successful
  
  Upcoming Work

Will continue working with 3D data, and hopefully making the 3D facial detection a lot better at detecting fake faces.

Schedule

Made decent progress, but hope to move forward more as we are headed towards the end of the semester. In the next few weeks, our team will come together and figure out how to integrate our three parts together.

 

Emily

Things were going ok but then they were not! I managed to get a bit of facial data over to Jason, but then for some unknown reason either the RPi or the camera/camera firmware stopped working (some uvcvideo error) and the Pi can no longer detect the camera when running the picture taking script even though it’s technically there when I run “usb-devices” 🙁 Have been struggling with this for a while, but nothing yet. Might have to re-install everything on the Pi and hope for the best 🙁

In happier news, the servos turn a deadbolt now! I’ve also been working on designing the outer enclosure so that all the buttons are accessible and the camera gets enough field of view.

 

Joe

This week I was able to build the switching circuit. Theoretically I should be getting good power, but in reality I’m getting around 1/10th of our required amount of power. The coils are also coupling very strangely, as they seem to couple more intensely when further apart (around 2 door widths is where they are optimally coupled). Getting 30V, 10ma at that point with a 9k Ohm load. Short circuit current is 300mA. Theoretically the optimal power should be 1/2 open circuit voltage * short circuit current, so should be getting enough power, but that is not the case! Unsure what is going on at this point, so will need lots of help next week!

Jason Huang

Accomplishments:

• Updated codebase to detect facial curvature and three-dimensionality; work-in-progress
• Emily’s camera sort of works now; using 3D data from the camera to update my code as well
  
  Upcoming Work

Still trying to integrate my code with Emily’s facial data, and hopefully that will be done next week, since she has a better understanding of how to use the camera.

Schedule

I had a midterm this week, and an essay due by the end of the week, so I’ve been working on that a lot, which meant I was unable to work on capstone too much. The whole team will be meeting up next week to combine some of our work together.

 

Emily Wong

This week has been busy, with midterms and big homework assignments. However, I was able to get the proper python libraries to build on my computer and put point cloud data to .ply file for now. I have been working on building the python bindings on the raspberry pi. It seems that the raspberry pi does not have enough memory to support the compiling with the desktop at the same time. Even then, it often runs out of memory. I configured a 1Gb swap file to finally make it compile. This was already after I had tried to cross-compile using an ubuntu vm, which ended up being a cmake file disaster. For the servos, I was able to move around some weak servos at home using the metro. The bigger servos just came and I will be testing those, and starting to design the housing.

I am slightly behind due to work from other classes, and I hope to make up ground by finishing up integration with Jason. We have several meetings planned to get the 3D face detection up and running so we can do testing. As for the servos, after I make sure that the higher torque servos will work, I can start planning out the enclosure so that they actuate the deadbolt, and then most of our project will be done.

 

Joe Zhao

This week I ordered a bunch of more parts. I should have all the components I need to finish the inductive power. It’s hard to judge how efficient the power transfer is, given that the function generator seems to supply different max currents for different frequencies. While I have been waiting for components to arrive, I have been trying to characterize the max power transfer, and depending on the efficiency of the DC adapter I bought from amazon, I should be able to achieve about 2x the power requirement I had set during the design phase. Another aspect I have been working on is to design the circuit for the 2.1 mhm 555 timer to output at 100khz pwm. I believe that my math is correct, and once the timer arrives I can build the circuit and verify via oscilliscope.

The goal for next week is to spend most of my time building circuits, and have significant testing and data on those power systems.

 

Whole Team:

Despite having a lot of other work this week, we think that we made a decent amount of progress. 2/3 subsystems are nearing completion, arguably the most important 2 subsystems (embedded stuff and software), so we think that we are on good pace to close out the project.

Jason Huang

Accomplishments:

• Obtained facial data via online (http://www.face-rec.org/databases/)
• Updated code that takes one photo and sees if it is registered; will be using this to demo next week
• Wrote an additional function that takes every single photo in a certain registered user’s photo directory, and average out the facial features to make the facial recognition more robust.

Upcoming Work

I want to integrate my code with Emily’s so that when a picture is taken, I can compare the photo with the database of registered faces and see if anything matches. I hope to also extend my code so that it detects depth, since right now I can take a printed-out picture of myself and still unlock the door, so I am trying to prevent that.

Schedule

I traveled last weekend so was unable to get as much work done. Still working on integrating code with Emily, but hope that will happen soon (not sure if it can happen before demo, but I have something ready for the demo at least).

 

Emily Wong

This week we finally got our original camera so we could finally do some interfacing with the Intel realsense sdk and the raspberry pi. All of my time spent this week was working on figuring out how to install all the libraries required to use the SDK, and figuring out how it works to get pointcloud and rgb data. So far, I’ve been able to get pointcloud data to be visualized through streaming it realtime to the pi. I was also able to get the RBG camera feed to sync with the pointcloud. However, I’ve been having trouble with the SDK getting the full pointcloud+rbg instead of it auto filtering out the background. I also need to figure out how to capture pictures instead of streaming video, and save those in formats that are useful to Jason. I think that I’m a bit behind since figuring out the SDK has been a pain, since there’s very little & bad documentation. Hopefully I should be able to figure it out on Sunday to get it working in time for the demo.

Joe Zhao

This week I got a lot of the parts for the inductive power. I spent the week assembling the coils and the rectifier. So far, it seems like there is a decent amount of voltage being matched on the receiving end. The only issue is that the amperage is kind of low. I am not 100% sure if this is due to the coil itself, or the fact that the function generating I’m using has a maximum current based on the voltage. I wanted to make the switching circuit, but it seems like I made a mistake when ordering the PMOS. The actual IC is way too small to be mounted on a breadboard, and also too small for me to try to solder wires to. I’m currently working on seeing if there are other options that I can do to connect to the NMOS, but it seems like I may need to order different PMOS. For next week, I hope to get all the MOSFETS so I can get the switching circuit, and then also the voltage regulator to get the correct amount of voltage to the RPI.