7/17/14 RIT Arm Complete and Durability Tests!

Today was spent doing the final stringing and tensioning of the RIT Arm.  Overall, the arm works pretty well.  The only part that still sticks is the thumb.  It's sanded well, so I figure the thicker string is having trouble moving around the sharp curve in the thumb tube.  We'll have to work that out in the redesign.  We also changed the elastic bands of a few fingers to get them to the same tension of the rest of the fingers.  Here are a few pictures of our completed RIT Arm.

After finishing off the arm, we decided to do durability tests on the Cyborg Beast.  This included dropping the hand onto concrete from one story, three stories, and down a long stairwell several times.  The hand did very well in the drop test.  The only damage was in the cracked rails on the gauntlet that hold the Velcro in place. We aren't surprised they broke because the rails were very thin.  A few small modifications could beef it up.  Otherwise, the hand only suffered scuffs and a loose tensioner occasionally popped out.

After the drop test, we simulated a harsh environment by sandblasting the hand.  Sand got in all the joints and gummed up the entire system.  This was expected.  Any joint system would get stuck, no matter what it was made of.  Rinsing off the sand got the joints mostly unstuck.  At the same time, we learned that the Velcro straps work when wet.

We also printed the palm for the Modular Gauntlet and a test block.  Surprisingly, the snap fit actually worked!  I was expecting the prongs to break of the ABS to be too rigid but it worked great!  We posted a video about it to e-NABLE (https://plus.google.com/communities/102497715636887179986) and will eventually apply the slots to our mid gauntlet!  Yay we're contributing!

That's all for today!

Alex + Sam