Well, a selection of my photos from 2011 are finally up. You can find them @ http://www.aisaku.com/photos/2011-2/

2011 was about getting back on track and remembering how to win.

It turns out that with a little hard work and with a little time eventually good things do happen; these good things did however keep me really busy. So busy in fact that I didn’t even bother to put any of my photos up here (sorry Mom!). For the 2012 I have some pretty concrete resolutions.

1. Do a better job taking time out to do cool things and cool projects
2. Document anything that I do that was pretty cool. I wish I took photos of my AV shelf build or the coil-on-plug conversation that I did on my car
3. Take more photos. I went to some cool places in 2011 and I didn’t bother to pack my SLR. Turns out my phone takes some pretty good pictures. I need to take more these.
4. Update my website more often.
5. Become a better writer and get published somewhere that isn’t here. I have some good ideas but I need to finish them and get practice writing real sentences. As a consultant, I have been reduced to bullet points
6. Get in better shape
7. Eat better

The photos taken so far this year are up on the 2010 photos page.

background

For a while I have maintained a little webpage. I hurriedly put it up because I needed a place where I could easily and quickly dump nearly a thousand photos so that my friends to get copies for themselves as well as view photos. Already owning a domain and some hosting, I put up a site using WordPress as a CMS and using NextGen Gallery to deliver photos. Back then, using WordPress as a CMS was not nearly as good of a choice as it is today. Back then it was a tough decision between using Joomla or Drupal and losing the ability and ease of WordPress for better functionality or choosing to depend on plugins with WordPress. Assuming that WordPress would keep improving even though 2.4 and the themes available for it were not so amazing, turned out to be a good leap of faith as WordPress 2.8 and now 2.9 are pretty amazing.

The initial goal of my site was to make my photos available as nice web resolutions as well are reproduction quality resolutions so people could grab copies for themselves. From there it kind of took a life of its own. Slowly I added pages do document the projects I did, the art that I tried to do, ways to contact me and a blog to try to keep pace with my life. Then one day I woke up and realized that while I loved my photography, the main focus of of my page should be my projects because they really show more about me than anything else. That coupled with the fact that potential employers started asking for web portfolios really drove that change. As the functionality of the site expanded, I thought it looked really quited dated and not very inviting. Its simplicity seemed to save to an extent, but it certainly was no looker (see below).

Getting the momentum I needed to make a change was hard to come by. After suggesting that someone get a website to display her photos and noticing that a friend was looking to make a website was the kick in the pants that I needed to get off my butt and implement a new theme.

After playing around with a couple of themes, I was ready to buy one when I discovered a free template that I liked. It turned out to be a little broken and needed some severe rewriting to make it do the things I wanted it do when I wanted it to do them. However, its probably better that I rewrote a theme that was free than one I paid someone for.

One of the problems with almost all the free WordPress themes is that they almost never have any of the top shelf features. Themes using jquery for awesome drop down menus and news feeds are just starting to show up; and none of the free themes had the visual pop of many of the themes of the top shelf themes. After looking through a couple dozen themes, many of which were going for ~$50 I realized that the cool visual effects were all pretty similar and were all using the same FREE (for non resale use) image slider: “cu3er.” cu3er was supposed to be easy to implement, so I took the plunge. It wasn’t too bad. Download it, Unzip it and start making it work.

the config.xml file

cu3er is pretty damn well documented which made my life pretty easy. Working off the demo, the slide show was very slick, however I wanted to utilize a few features that really make  me love cu3er. While the transitions are really slick, the thing that really puts this slide over the top is the ability to add fly in overlays that can display text. With some visual trickery like semi-opaque frames these decriptive captions make a slider more than just a piece of eye candy, they can be used to create a visually attractive introduction that summarizes the content of a site. Additional code can also be added to make both the description and the image behind it click-through-able so that they can serve as a link to whatever is being described. Suddenly, the eye candy is super useful. Of course you also want the images to also rotate to make this object live and fulfill its purpose. To make all of this happen you need to edit the config.xml file that comes with cu3er. The first step is to add the following to the settings section of the file:

The settings above set options such as rounded corners, time options on the slide show and the colors/fonts of different objects/controls. If you want to dive in and customize this, I highly suggest looking in the cu3er documentation. While they do not have nice sample code; they provide detailed descriptions of the options available.

Once the settings are programmed in, the actual descriptions, links and urls need to be included for each slide. This can be done as follows:

Then its just a matter of saving the file (the screen captures with highlighting are from notepad++). Note that I renamed the images folder images2 to prevent naming conflict with the images file in the WordPress theme I was using. Note that you MUST include paths from the content file onwards or the images will not load. This is not apparent when you run the demo.

integration with the theme

If I opted not to use a theme that auto-generates the home page via PHP, integration would have been a little more straight forward. Having unzipped the cu3er download previously,  the next step was dropping it onto my server into the folder of the theme that was planning to use, I added the following code to the index.php (it might be differently named in another theme, but we want the php file that generates the home page):

The  above code should be added in the place where you want cu3er to appear. Since I wanted mine to show just under the header, I added those lines just under the PHP code that fetches the header. There are some important items here: by using the swfobject.addLoadEvent(function(){}) call arount the swfobject.embedSWF function we are telling the slideshow to draw in a way that makes it compatible as tested with IE 6 and 7 as well as Firefox 2.0+. Without the additional load event, the slideshow will only render correctly in IE8, Firefox 3.6+ and Chrome. I feel like very small  amount of delay thats only noticeable when loading over slower connections is an acceptable trade off for that kind of backwards compatibility. Also, take note that there is an extra div wrapper in my code that is used to put the shadow graphic on the page.  (a copy of the shadow image is near the bottom of this page)

If you aren’t using a theme that generates a home page or if you just want to put cu3er on a standard page, you can just use the same code that is provided in the html file in the demo or you can use my version below:

Again you want to add this into the right place. You can see the </head> and <body> tags that indicate that it might be a good idea to the have the javascript calls in the header and the actual box in the body. You need to do this to make sure that it works right in Firefox. Also adding the line to the top of the javascript script (the second one, not the call): swfobject.switchOffAutoHideShow() supposedly also helps resolve problems with Firefox 3.5 when adding cu3er via html. I never ran into those problems, so I cannot be sure that line is needed.

Again, you can put the items where you want. Note: the only real difference between the demo and the version that I have above is that I added the wrapper with a shadow. the shadow image is below (click for full image):

The only unresolved issues have to do with CSS and they aren’t things that I care too much about. The shadow is more exposed in IE to the point where the cube looks back/top lit vs the front/top lit shadow that shows in Firefox and Chrome.

conclusion

That pretty much wraps it all up. Not too hard at all to add some amazing visual effects that can really make your page pop. Feel free to cross browser test my site. you will notice that the CSS isn’t perfect, things fly a little out of place in IE6, but then again I don’t know of too many sites that look the same in IE8 as they do in IE6.

My code for the cu3er implementation works great in Chrome, Safari, Firefox 2.0+, and IE8/IE7/IE6.

I still am thinking about rolling this into a free theme as soon as I get the hang of using PHP to generate XML. Hopefully that will happen soon! UPDATE: Due to the cu3er license, I will not be doing this.

Any code on this specific page, people are free to use. Project was completed started Feb 26th, 2010 completed Feb 27th, 2010.

The Vampower, a power saving power strip, is an award winning design project that was part of a joint class in product design and development (PDD) co taught by the FW Olin College of Engineering, the Rhode Island School of Design (RISD) and Babson College. The team that worked on this project included two designers from RISD: Will Harris and Danny Kim, two engineers from Olin College: Bennett Chabot and myself, and a Babson College business student: Anand Virmani.

This product design prototype was the result of work in user interaction, design for manufacturing, electrical engineering and many hours of sweat and hard work. It was completed over Fall 2008 with minor work extending into the Spring of 2009.

the background

It all starts with a problem. The problem is that 129 million mega-watt hours of electricity is lost every year due to so called latent power use. This kind of latent use includes obvious competitors like stereos and computers in standby to the cell phone charger that sits on the outlet every second of every year; quietly using power. To understand the magnitude of that power, latent or vampire power we like to call it uses approximately 10% of the residential power used in the US every year. In terms of power generation it is the equivalent of building 6,000 wind turbines that are 600 feet tall. Since monetary figures can also be drivers for purchasing a device that saves power, we estimated that the average home owner loses $160 to this vampire power use. It is definitely a big problem, but some devices like a cable box or an internet modem don’ work right if they are disconnected from power; so the real world impact regarding the amount of energy savings is less but most likely still very significant.

In addition to the green reasons for wanted to build a new power strip; the power strip is one of those items that companies are always trying to redesign. From simply rotating 90 degrees to the more exotic items on the market like the power squid; people have been searching for a better power strip. We decided that since we were looking to solve the green problem with power strips, we would also take a shot at making a more user friendly and more appealing power strip.

The result was the Vampower power strip; a truly different solution…

the problems and our solutions

To really understand the scope of the problems that potential users of the product that we were endeavoring to design would face, we did a large number of observations of people interacting with their power strips as well as a large number of interviews. From that user data we were able to discern a number of unmet physical needs, as well as a desire to save power if it could be done. Through a process of design exercises and a few more rounds of user feedback, we were able to come up with a rather concrete set of requirements.

To share a few of these requirements and the solutions that we devised to satisfy, I will first share a pair of physical/form factor requirements:

The first one I want to share is the idea of modularity, a notion born for the need for flexibility.

We photographed in many places where power strips were used.  In very few of them did we see 6 or 12 receptacles in use (the common number on a strip). When less were needed, it was not a huge problem, but often when someone wanted to have 8 devices attached to a 2 receptacle outlet there was often either a splitter in use or some sort of daisy chaining going on; creating a potentially unsafe and definitely unsightly nest of wires. Our solution to this problem was the introduction of modularity into the power strip.

We considered other alternatives to our final design. From outlet pads to Power-Squid like form factors we settled on a set of rotatable modules that could be connected and disconnected to build a power strip of just the right size. It was one of the ways that we sought to put the right number of outlets in the right place and cut down on the clutter.

The second is the notion of discrete size a solution to the need for more accessibility.

We found through our research that people often tried to fit their power strips out of sight and tucked into small spaces. This creates a problem when using traditional power strip as the AC-DC power converters used in many of our modern electronics take up so much space that only 4 of the 6 outlets are used on a power strip, meaning that a second power strip is needed. Items like the Power-Squid solve this problem but at the cost of taking much more space. Our goal in attacking this problem was to make every outlet on the strip more accessible without increasing the form factor to the point where the item was no longer space efficient.

We looked at a variety of alternatives and settled on making something with rotating plugs. Through this design we were able to avoid increasing the footprint of the power strip dramatically, while at the same time we were able to make it more likely that user would be able to access every single outlet on our power strip.

The next two requirements and solutions have to do with effectiveness as a power saving device. In the most basic sense, the best way to save power would be to simply turn off the power flowing to devices and turn them back on again. By observing people who did this regularly with their power strips to save power, we identified several distinct “pain points” that stood between people wanting to save power and actually doing so. I will share two critical items below:

First, is turning the power strip off after use.

One of the subjects that we encountered wanted to “green (her) lifestyle” and so took great pains to turn off her power strips that were not in use. For aesthetic reasons, she hid her power strips behind other objects. To turn them off she used a walking stick to flip the switches as they were not easy for her to reach. From these observations and others like it, we were able to determine that a device that we wanted to build would likely be placed somewhere where accessing the device would be difficult and that we would need to allow users to easily switch off their devices. Our interviews also provided another design/engineering target, our users want to turn everything completely off. They didn’t want another device that “leaked power.”

We looked through many different ideas on how to turn off the power. While many of our users said that they would have no extra problem taking an extra step to turn their devices on, it was a major problem to remember to always turn them off. We thought of remote hard wired switches, wireless devices, an iphone app and other countless ideas before settling on a self calibrating circuit that sensed current and simply turned off when the current dropped below a % threshold from its peak use. This would prevent users from forgetting to turn off the device, while walling devices from still consuming even a little bit more power.

The second item is the reverse of the previous process. We needed an elegant way to restore power to our devices.

Again we are faced with the same general scenario as above. Our users tended to hide their power strips, so turning them on often involved uncomfortable reaching or use of the walking stick. In this case, doing the turn on operation needed to be remotely activated. There are many AC-DC converters that can sense when they are connected to devices and thus activate and throttle their power that way. Unfortunately, since we aren’t looking to sense connectivity we had for other ways to activate our devices.

Because we did not want our users to have to keep track of a remote, we looked at motion sensors and current sensing mechanisms. Our users surprisingly liked the idea of a clapper as long as they did not have to worry about it accidentally turning their devices off. Since this was going to be an on only mechanism; we decided on using a clapper type sensor to turn the power strip on for 30 seconds after which the current sensors cut power to any device not using enough power to be determined to be “on.”

the product

Once we found our requirements and synthesized our user feedback to the point where we felt like we had solutions to the problems that we wanted and our users expected us to solve. Through several iterations of presenting prototypes to our users, we arrived at the following design:

We decided on three different components that could be plugged into each other. The first was the clapper sensor and timing mechanism, along with more standard tech found in high end power strips like power filtering and a circuit breaker. The second was the “smart power” module with the current sensor inside. This smart module would be the backbone of the product as it fulfills the promise of the product:

An exploded view of the product shows the current sensor inside a housing with a 4 plug connector (pins not shown). The idea would be to use three pins for the standard electrical pins while using the 4th as a signal pin to turn on all of the “smart power” modules. The last component to our system was the “constant power” module, a connection that would always provide power in the manner of a regular power strip while retaining the benefits of modularity and accessibility. We built this component so that our users wouldn’t need another power strip to connect their devices that they always wanted to be on like their DVR or broadband modem.

the business model

After we built the product we kept in mind our costs and figured out that we could offer significant value to our customers at the $30-$40 price point while we would be able to make a significant profit from the device. In terms of surveying our users on what the final package should look like, we settled on a four module basic package of 2 “smart power” and 2 “constant power” modules in addition to the master switch/clapper. The green lines indicate the “smart modules”. (power cord not rendered)

conclusion

We wished that we had the resources to take this further, but as there was no real place for IP (except on the design of which other copies already exist) we did not decide to take this idea further. There are also some problems that were not fully solved in this exercise. There is no way to differentiate between the kinds of modules except for via coloration. One of the ideas that we wanted to implement would have been a way to differentiate the models by shape.

Though the project was not as polished as we wanted it to be, we were able to make prototype(s) for testing and found that the idea was well received. We called this one a success as it was deemed the best design at our expo and photographs of our work were taken to be used in the RISD admissions materials.

I don’t think that launching a new website is really something worthy of being considered a project; but in this case it was a pretty good sprint. I think it looks pretty good (except in IE) for someone who really didn’t know much PHP and had only a basic understanding of how wordpress templates work (this site is using wordpress as a CMS). For me, it was a pretty sizable undertaking. I started with a template that had some jquery functionality built into it. After reformatting my pages to work in the new theme, I started building it out, changing the template files to try to get theme to do what I want. The person who did the base work deserves props for being a great guy (or gal) who was willing to give away their work for free. For that reason alone, they are awesome. That being said there was enough stuff that did not work that I was tempted to go just buy a theme somewhere for a better starting point. However, I like struggling with things until I learn how to make them work, so it was definitely worth the $30 saved. Money+learning experience= win. Even though I did not build this out into a proper theme where some of the new elements that I added like the cu3er slide show can be easily configured; I consider this to be a smashing success on my part.

If I decide to figure out how to make my work into an actual theme and roll it out with due credit and permission from the original author, I will need to learn how to use PHP to generate the XML config file that the cu3ber image rotator uses to store its settings. I am sure that there will be other challenges as well, but when I can wrap my head around that; I will reconsider figuring out how to give away this wordpress theme.

I also think my old website which was built for speed in implementation needed to be updated to take advantage of the amazing visual tools out there today. Compared with the old home page, its like comparing a Gameboy screen to an HDTV. Below is a snapshot of the old page pulled from Google’s cache.

Now that I really think about, maybe it wasn’t so hard after all. It just took a long time. Also: even though cu3er is a little slow, its AWESOME.

This project was completed during a course on robotics taught by Prof. Dave Barret at Olin College. The final project for the course, the goal of the project was to navigate a maze using a Surveyor robotic platform. As part of this project, additional sensors were added to the robot. This writeup will focus on the addition of the sensors because they illustrate an example of engineering problem solving skills as we extended the capability of a platform beyond its original design. This project was completed with collaboration from Leif Jentoft.

background

The challenge of this final project was that the surveyor platform only contained a single sensor, a video camera. Furthermore, the platforms were running a parallel programming language called Occam Pi that made making the maze solving algorithms pretty easy, but adding sensors difficult. Because of the distinct difference between the colors of the walls of the maze and floor, a color differentiation algorithm using the camera could be successful in navigating the maze. All of the other teams chose to take this approach. While a few of the teams did have success with this approach, we chose to install a few Sharp infrared distance sensors instead.

We knew from the beginning that there were significant issues with this approach. Like most sensors, the Sharp IR distance sensors that we were trying to use output only analog voltages between  a low voltage (almost zero) and the high power rail.  The Surveyor used a Blackfin DSP chip as its CPU. By design, it was limited to having only digital inputs so we needed to provide the Surveyor with some sort of digital values so that we could use IR distance sensors to help us navigate the maze.

The Occam SDK for the Surveyor platform could not yet read serial values at the beginning of the project. While this functionality was added to the  SDK midway through the project, it was too late for us to use.

the micro-controller

For this kind of application, there were many choices of applicable micro-controllers. Because I had worked with a PIC extensively in the past and my collaborator was also very familiar with PICs as well as the C code used to write code for them, we chose to use a PIC over other available solutions. The PIC we wanted was a PIC16F690; it accepted a wide range of voltage inputs and had everything we need in a very small package. On the downside, Microchip (the company who made this PIC) didn’t offer a free compiler to use this PIC16 series controllers and we were unwilling to take the time to figure out how to use third party libraries. For that reason we opted to use an overpowered PIC18F series PIC. Because the Surveyor used 3.3V and not the more standard 5v as its source, we needed to use a low voltage PIC to ensure proper operation. We opted to use a PIC18LF2221 because it had built in math functions, plenty of analog and digital IO pins and an internal oscillator that we could use to clock the PIC. The LF indicates that it can be used at lower voltages.

The plan was to use the PIC to translate the analog output from the IR distance sensors into a PWM (pulse width-modulated) signal. Because both the Surveyor and the PIC had processors that were clocked, we could effectively translate the analog signal into a digital pulse. We chose a linear relationship between the length of the pulse and the voltage to help determine the distance. Because there were problems changing inputs and accessing different digital inputs on the Surveyor, we changed our initial conceptual design from one PWM signal line per sensor to a scheme that used inputs to tell what sensor was being read and then had the value sent along one PWM channel that was used by all the sensors. We considered this part of the design to be a work-around for a bug that was either in the base code of the Surveyor’s Occam Pi based code or in the hardware itself. Because we didn’t have another robot to debug on, or much time to figure this out; we simply used the workaround as a solution. We considered this less than ideal as we knew it would make the PIC code seem a little messy when compared with our ideal design.

circuit

The circuit diagram above describes the wiring of the PIC and the sensors. The 10k resistor between ground and pin 1 as well as the 10 micro-Farad capacitor bridging power to ground  between pins 19 and 20 are needed to run the PIC without an oscillator and are not particulars of our design. The sensor ground and power were also filtered to clean up the analog signal from the IR sensors. The important items that were included on the design are single PWM signal out line and the four sensor enable pins that match four different analog inputs.

code/logic

After setting the proper configuration bits we then worked on the logic needed to make this system work. The code needed to run this PIC was written in C using the Microchip 18C compiler and associated libraries. The logic portion of the code used to run a single sensor the example shown below.

Inside of an infinite while loop (because we want our code to always be running on the PIC waiting for input signals), we used the following logic:

if (INTCONbits.T0IF == 1 && PORTCbits.RC4 ==1 ){ //if the timer interrupt goes off…and sensor 4 is selected

INTCONbits.T0IF = 0;  //reset the timer interrupt flag, we now have ~1000 clock ticks to process everything else

//get RA0 analog in

ADCON0 = 0×03;                           // select AN0 and set GO_DONE bit to start A/D conversion

while (ADCON0bits.GO_DONE); // do nothing until the A/D conversion is done

pwm0 = ADRESH/4;//input from RAO, 8 most significant bits

//generate the pulses

if (counter < pwm0){PORTBbits.RB0=1;}

if (counter > pwm0){PORTBbits.RB0=0;}

}

When the Timer (set to expire every millisecond) went off and if the Surveyor had set the enable pin for this particular sensor high, then we set the digital out to high if the scaled analog input is greater than a counter than counts the number of milliseconds that have passed. We set the bits low when the counter is greater than the analog input, thus generating a crude PWM signal.

The counter is incremented at the bottom of the loop.

counter++; //counts the number of milliseconds

if (counter > 50){counter=0;} //reset counter to set PWM to 100Hz

When the counter goes over  50 we reset the counter to 0 so that way we get a 100hz PWM signal as an output. We then sampled the sensors to allow the  vehicle to follow walls and see open spaces in front of it. This logic code was the same for each sensor with the exception that the enable bit and the analog input were received on a different ports.

conclusions

In conjunction with wall following algorithms, our robot was able to solve the maze. Though, other teams succeeded in using the camera to complete the challenge, our robot was also successful. Our work on this sensor integration was preserved so that students in the future would be able to easily integrate analog sensors into the Surveyor platform.

This project was shown at Olin Exposition in the Spring of 2008.

This project is being written up almost three years after its execution so the writeup may be a little hazy.

There were two collaborators on this project: Eamon Doyle and Clark McPheeters.

background

The project started with a silly idea. As freshman at a small engineering college my roommate Eamon and I were always trying to think of creative ways to do something novel. We had heard from the upperclassman at the college about all the crazy things they had done and as the last incoming class prior to our schools first graduation; there might have been some inkling of wanting to also leave a legacy. On a whim, Eamon purchased a few USB fingerprint readers from eBay. Now back then, biometrics were novel. Facial and fingerprint recognition were far from standard gimmickry on laptops, and the notion of password-less protection was so novel that it still seemed like some awesome, super secret, spy-movie worthy way to secure data. However, unlocking a computer with a fingerprint reader is slow and kind of lame. In the movies it was always a combination of biometrics that opened a door. Since we hard these fingerprint readers, we figured that we would give it a try, one biometric at a time.

the SDK

Reading the fingerprints were easy, but the application that came with the readers was only good for filling in passwords. We needed more flexibility than that if we wanted to actually do something. As freshman, we knew nothing about embedded platforms of any kind and the only programming experience that either of us had was on windows PC’s. After unfairly blaming our respective high school computer science departments for that deficiency, we set about looking for a .net SDK (software development kit) that we could use to trigger an external device.Through a little work and a lot of luck, Eamon hit gold. He found a company in Lithuania that thought that we were pretty cool kids and gave us a copy of their thousands-of-dollars-for-sale SDK for free, the only stipulation being that we send them pictures of our application, the story of our project, and put their logo on our poster when we presented. We didn’t know it at the time, but the VeriFace/VeriFinger software would roll out in about a years time as the software behind the IBM/Lenovo biometrics packages.

Once we got the SDK up and running on the PC it was time for me to put my C++ skills to use. Using their demo as a starting point I realized that the easiest way to make the system work would be to use the serial port on the device to output a high string to open the door when a finger was recognized and low string all other times. Looking back, now it seems like a very messy solution, but as a freshman I simply didn’t know any better. After writing a few lines of code and more than a few hours, the app was done, we had a faint but consistent signal output when the system recognized a previously enrolled fingerprint.

The picture above shows the finished software in action. For the most part the GUI from the code example was retained. Databasing and logging features were added in addition to the serial signaling on successful print match.

the hardware

While I was coding the other members of the team, Eamon Doyle and Clark McPheeters were busy making the parts needed to make the system work. The first order of business was to take the lock out of the door. There weren’t rules against this when we were freshman in college…but there were rules against it by the time I was a junior. Views of the disassembled lock are below:

Once the lock was disassembled, a solenoid was selected that would be small enough to fit into the empty space and pull the locking pin on the door lock. One of the design goals was to make sure that the keys for the door still worked in the event that the system stopped functioning, as the system would be running on a Windows machine we thought this to be a neccesary precaution. As freshman, we all learned how to CAD, but for the purposes of conceptual design, things were still done on paper first. We also didn’t want to damage the lock at all, so any mounting would have to be done without screws, glue or brazing. To make it work, Clark and Eamon set about designing a solenoid mount.

As shown by the above placement, a mount that took advantage of the geometry of the case would hold the solenoid in place. We also needed to make a new plate to replace the one that keeps the handle from turning and therefore the door from opening, By actuating that plate we would be able to open the door using both the key or using the solenoid to move the plate. Once the design was set, a CAD model of the lock and new pieces was made to ensure that everything would fit together as planned.

The next step was actually making the pieces. From the CAD design, Clark and Eamon milled the pieces out of aluminum stock. The mount was made first:

As can been seen from the pictures above, the geometry of the mount is precision made so that it can make use of the cuts in the lock to hold the solenoid in place. The next step was to make a replica of the plate that we need to move. We could not modify the original since we would have to restore the lock completely to original condition once we moved out at the end of the year. Photos showing the manufacturing of the plate are below:

Like the mount, this was also milled out of aluminum. Given the training that we had at the time, it was the best choice. It would probably be a good choice again too, if we had the access to the same kind of machinery and could just find small blocks of scrap aluminum stock lying around.

putting it together

Once all the components were made, the lock needed to be reassembled with its new parts and tested. At this point, the software was working, but we knew that we didn’t have the power needed to open the solenoid just coming from the serial port. We knew we would have to take some DC power from the inside of the PC to make it work. What we didn’t know was how much power would be needed to operate the solenoid. Therefore, testing with a power supply served two purposes. Photos of the assembly and the testing are below:

On the first try the testing was successful! All that was left was to present it…and eventually install it on our door!

presentation/epilogue

On the day of the presentation, we were ready to go. Looking back, we were really proud of the work we had done. Most of us had a pretty rough semester; but the world seemed all better now that we felt like we had something pretty cool to present. We took the time to make sure that our poster /demonstration stood out too!

People seemed to think it was pretty novel too. Though I think the facilities workers liked it the most. Their managers were much less thrilled by the latest in alterations to campus equipment. Of course, as soon at it was over; we installed it so that we would use it from the week after our presentation to the date after which we were kicked out of the dorms for the summer.