As I stated in my post on mop design decisions, the maximum water capacity (and by extension the area that can be mopped by the robot) is heavily dependent on the how much of water the mop can absorb. Ideally, the water tank should run out just when the mop head is saturated with water (and thus not leave dirty water that it can’t suck up behind on the floor).  To figure what kind of a range I’m working with, I decided to measure the absorbency of the microfiber cloths I purchased to use as my mop head.  The product page says the cloth can carry up to 8x its weight in water, but I’ve been burned before and wanted to put that to the test.

Methodology

The way I tested the absorbency was by measuring the weight of the microfiber cloth at various levels of wetness; dry, damp, saturated, and oversaturated.  I performed the dry measurement by weighing the cloth fresh out of the packaging; the damp measurement was performed by soaking the cloth in water and wringing it out; for the saturated measurement I simply held the soaked cloth over the sink until it no longer dripped; and lastly the oversaturated measurement was taken by weighing the cloth immediately after soaking it in water.

The most likely wetness of the cloth in a real-world scenario is probably somewhere between damp and saturated, since a dripping mop head would still leave dirty water on the floor.

Results

The dry cloth weighed in around 33g, in line with the data found on Amazon.  If I trust the advertising, this cloth should hold around 250mL of water. Let’s see about that…

The wet cloth was 106g, so roughly 75mL of water was absorbed (since 1 mL of water weighs a gram).

In the saturated case, the cloth weighed 207g and held about 175mL of water.

Even the unrealistically oversaturated cloth held only 200mL of water, which is still less than product’s claim of 8x its weight.

Conclusion

While this microfiber cloth clearly is not as absorbent as was promised, the 175mL of water held by the saturated cloth still bodes well for the overall capacity of the mop module.  It would only take a single cloth to match the capacity of the Braava Jet, and four or five to match the capacity of the Scooba, assuming that the entire cloth gets saturated during cleaning.  I still have to design the mop module and determine how I’ll arrange the cloths and attach them to the module, thus dictating how many cloths I can fit in the design, but these initial results seem promising.

It’s been a while since my last post, and quite a bit has happened in my life.  I’ve graduated University of Delaware with my Bachelor’s and have two classes left until I finish my Master’s Degree, which I hope to do this Winter.  I will be taking this classes remotely from my new home in Pittsburgh, where I’m also working full time at Aerotech Inc, a motion control solutions company.  I’ve been there for about a month now, and it’s been very interesting so far.  I’ve learned quite a bit about how larger companies operate as well as some professional programming styles.  I’ll most likely be working very closely with DSPs and FPGAs, and I look forward to learning a lot about them!

For the past two years I’ve been using the Samsung Captivate, which is a variant of the Galaxy S, as my phone.  It’s an Android phone and has served me well.  However, when I originally bought it I didn’t realize how much I would love it.  It was really the only Android phone available on AT&T at the time and since I knew I didn’t want an iPhone, it’s what I got.  Let me just say I got very lucky.  As I’ve recently learned, the Captivate was used as a model for the Nexus S phone by Samsung and since the Nexus line always receives updates straight from Google, it was fairly easy for developers to port the newest Android versions to the Captivate as well.  This leads me to why I love the phone.  The software that it came with was pretty crappy.  Samsung was not considered the nicest manufacturer at the time, and was trying to throw out tons of phones in attempt to battle the iPhone.  As such, my phone wasn’t slated for many software updates and the skinned version of Android wasn’t it top shape.  Because of the many crashes I had to endure over the life of my warranty, I decided to root it once it expired.

Using Heimdall and the CyanogenMod website as a guide, I managed to successfully root it and install CyanogenMod 7.0.  It was an amazing change of pace to say the least.  New options were suddenly open to me.  Instead of software created by a huge corporation with little concern for providing all the bells and whistles, I was suddenly using an amazing culmination of the thoughts, ideas, and innovations coded by the developers over at XDA.  Features that I didn’t even realize I wanted were suddenly open to me.  It felt like an entirely new phone.  And for someone like myself who always wants to stay on the cutting edge, the amount of ongoing development was wonderful.  I could easily reflash new ROMs on my phone and stay up to date with the newest versions of Android.  Over the past year I’ve kept my phone merely weeks behind the latest version of Android, something manufactures can’t claim to have accomplished.  In fact, via XDA my Captivate is currently running Android 4.2.1, Jelly Bean, which is actually an upgrade ahead of my new phone.

Deciding on a replacement for the second most valuable piece of tech in my life (the first being my laptop of course) proved exceedingly difficult.  The Android market has changed drastically in the past two years and as such there are a huge number of options available, and while I try to keep up with the latest and greatest in mobile technology, I still had no clue what I wanted.  After some thought on the phones available on my new carrier, Verizon, I narrowed my options down the Samsung Galaxy SIII and recently released HTC Droid DNA.

The SIII was an amazing piece of hardware, with a huge following and massive developer community.  It also was, and still is, the most successful Android device.  The main drawback, however, was the fact that the phone was around 8 months old, which is an eternity in mobile years.  With a dual core processor, it had a hard time competing with newer devices, at least as far as benchmarks are concerned.

The DNA, on the other hand, was barely a month old and had a quad core processor and 1080p display.  The only thing that had me worried about this phone was the lack of developer support.  Compared to Samsung, HTC is a rather small company and hasn’t been able to achieve the same success as the Galaxy series of phones.  It can’t afford to push a flagship phone to all the carriers or advertise as heavily as Samsung has done for the SIII.  As such, the DNA is only available for Verizon, a rather disliked corporation as far as XDA is concerned, and has garnered comparatively little attention when considered with the SIII.  So while I realized the DNA had everything I wanted in terms of hardware and specs, I knew it wouldn’t be able to match the amazing amount of development I had become accustomed to on my Captivate.

After much deliberating I finally went with the DNA due to the hardware specs and build quality.  I decided that while the development may not be as good, it might encourage me to do some developing on my own.  And even if I never do get around to it, Android has become very stable in the past few years and as such I won’t need to deal with the same amount of crashing and problems the original software for my Captivate provided so at the very least I’ll have a working phone.  It’s been about a week since I got the DNA now and I’m definitely not regretting the decision.  It’s an amazing phone, feels fantastic, and is a pleasure to use and I look forward to tinkering with it for the next 22 months!

Well, I’m late for my second post of the year, so that certainly bodes well for the future.  Anyways, I just wanted to mention that I’m really excited for some of the projects I have on the horizon, specifically the Iron Man/Awesome helmet I want to build.  I got the Wild Planet Spy Car in the mail a few days ago and it’s awesome!  The video is black and white, and a little distorted, but I assume the fuzziness is mostly a result of the wireless connection or the camera and not the display itself.  I also ordered a Mind Flex game for $10 which is a steal!

For those of you who aren’t familiar with Mindflex, it’s a headset with a built in EEG sensor that can determine brain waves.  It can differentiate between several frequencies that represent how relaxed or focused you are.  I was thinking I could somehow couple this with the video headset to form an augmented reality helmet of some sort.  Anyways I’m excited about it and look forward to playing with it at the very least.  I’ll post more when I get it and when I hack the video headset!

Between school and work I’ve had a hard time sitting down and getting stuff down for myself.  That’s why, this year, I’ve set several New Years Resolutions that pertain to bettering myself and focusing on things that are important to me.  The resolutions I have planned are as follows:

• Run 100 miles
• Read 24 Books
• Finish 12 Projects
• Blog once a week

Over the past couple of months I’ve realized that I have many thoughts and opinions that just kind of stew in my head until I forget about them.  So I thought it’d be nice to create a neat repository where I can write down my thoughts and opinions once they’re fully formed and ready to leave my head.  I hope that by doing this I will be able to inform or influence the opinions of others and receive feedback on a lot of my own ideas.  In addition, I’ve been focusing a lot on self improvement lately and hope that this blog leads to me improving as a writer, among other things.