Thursday, March 15, 2012

12 step engineering process

 This is the 12 steps engineering process about our latest change in the vex robot, SASHA 5.2. We have gone from SASHA 1, to SASHA 2,to SASHA 3, to SASHA 4, to SASHA 5.1 and finally we are SASHA 5.2, our latest vex or mindstorms version of the SASHA robots.

1. Define the problem - our problem is that we need an arm by tomorrow.
2. Brainstorm - we thought about our old arm idea that had only one arm in the front of the vex robot and the second design of our robot were we had two arms.
3. Research and generate ideas - we researched ideas from looking at other groups ideas which were pretty much all by the book, and then we decided to make our own design for the arm and put it on the top of the robot.
4. Identify criteria and specify constraints- we had many constraints that held us back including that we can only use one brain for the initial and final design, because we are using two brains for the testing, but we will have to change it back when we are done.
5. Explore possibilities - we have had several possibilities for the arm/arms on SASHA 5.2. we have had one arm in the front of the robot, one arm on either side, and now an arm on the top.
6. select an approach - we have decided to go with one arm on the top of the vex robot.
7. Develop a design proposal - we are going to construct an arm on the top of our vex robot, SASHA 5.2, which will be better than either of the other designs and well attached with screws.
8. make a model or prototype - we are currently working on constructing our arm on the top of the robot.
9. Test and evaluate the design using specification - we are going to test our arm with the vex micro controller and try to pick up the either the green vex ball or a tennis ball.
10. Refine the problem - we have created an arm on the top of our vex robot that will be capable of picking up and carrying the vex ball/ tennis ball.
11. Create or make solution - we created the vex arm.
12. Communicate processes and results - we have clearly documented all work on creating this vex arm on top of our robot.


Today we are currently installing several limit switches on to our new vex robot, SASHA 5.2. We had limit switches on it before when it was SASHA 5.1, but we took them off when we dismantled it for our new design of SASHA 5.2.

SASHA 5.1 had to be dismantled because we had two arms with two brains for our testing phase when we decided to go with two arms, one on the front, on on the back. Now we have decided that we would go back to one arm but change it from the front of our vex robot design and put it on to the top. SASHA 5.2 is clearly much better than SASHA 5.1 because now it is smaller, and easier to control.
 This is our new, smaller version of our current vex robot, SASHA 5.2. We have gone from a much larger, harder to control version of SASHA 5.1, to this smaller, faster version of SASHA 5.2.
As you can clearly see in the above image, we have constructed our arm on the top of our vex robot instead of two,one on the front and the back of the frame. You can also see that we constructed another frame to hold the arm in place that goes above the main body that holds the brain and the battery.

Wednesday, March 14, 2012

Today's Work

Today we are testing the amount of electrical output coming from our motors. We are measuring this electrical current with a digital multimeter. We also worked on printing our entire blog to put it into our binder.  However, our blog is currently blocked and outlawed in the public school system which we are in, so we are unable to make any adjustments to the public blog and page design, and we cannot print it.

Tuesday, March 13, 2012

Today we clarified that our vex robot, Sasha 5.1,  has two brains only for testing purposes. We decided that it would be easier and more efficient if we used two brains for testing and then we will change it back to one brain for the actual finished vex version, Sasha 5.1. We also have re-tightened our whole vex robot because some parts of it were loose and need to be tightened before we can start to test it again. We are unsure of what we are going to do next with our vex robot, because we are not sure if we should keep the new design with two arms, or go back to our old design with only one arm and add the counterweights back to where they were before to replace the second arm.     

Wednesday, March 7, 2012

Working with the Engineering Design Process

Throughout our project, we've had many errors.
Through the mandated use of the Engineering Design Process, we've been able to overcome these, and continue on with the development of SASHA 5.1.  The robot in it's latest form contains two arms, two brains, five motors, two transmitters, and requires two remotes to run.  We believe that right now, we are done with all developments and that no further ones will need to be made.
The robot, SASHA 5.1, looks like this:
Top view
Side view
 Some of the problems we've encountered have been:
  • Inability to pick up a ball (no arm)--This led to development of SASHA 5.1
  • Inability to hold ball
  • Lack of speed
  • Lack of power
  • Incontrollable arm
  • Extremely unbalanced robot (this led to several developments/changes)
  • Inability to turn
  • Lack of controller ability to control the robot properly
 Because we couldn't hold the ball, we added a separate mechanism to lock the ball in when we pick it up.  This required an extra motor, upping our count to 4 motors.  We then upgraded to extra large wheels, with a back wheel that has the ability to travel in 360 degrees.  Then, we added a counterweight in the back to prevent the robot from tipping forwards when we lifted the arm.  We experimented with different stopping mechanisms, and settled on a vex piece that would cause the arm to stop moving when it was pressed against the rest of the robot as the arm was lifted.  Later, we added a different arm on the opposite side to stop it from being unbalanced.  Our robot is basically complete, and we think that this will be the final product.
As always, subscribe to our blog and stay posted for additional developments.

Friday, March 2, 2012


As you know, we've had issues determining versions of SASHA in the past.
However, while this robot used to be SASHA 4.1, and was later upgraded to 5.0, it is now known as 5.1.  We've done too much work on it for it to be the same as the old SASHA 5.0, the miniature drone-capable robot.  It now has mine sweeping capabilities, two arms, and two brains.  It is larger than we expected it to be, and it is definitely not as fast, versatile, or stealthy as the original.  There is no way we could continue this construction without the robot being completely different from the original product, as our objectives have changed.  Although it's not a brand new robot, this robot is definitely new.  We may never see SASHA 5.0 again, but it'll always be a part of 5.1.  These additions have put SASHA 5.0 past what we've ever imagined for it.  Welcome to our lab, SASHA 5.1.

Thursday, March 1, 2012

Major change to SASHA 5.0

We're starting a major adjustment to SASHA 5.0: the addition of a second arm.  We're not sure how this is going to work, but the idea is that the second arm will create more possibilities for our robot.  It will allow us to do more in testing, usage, and competition.  Also, the arm will create better balance for the robot, because the arm that we have now causes the robot to tip over when it was raised will have a counterbalance.

This crude sketch shows how the final robot will be arranged.  There are two brains, and the other arm will be situated on the opposite side from the existing one.  In addition to this, we will probably be outfitting the robot with all four wheels the same.  The wheels we use will be the ones that are currently in the back (near the new arm's location).  We'll continue to let you know how this development is coming, and keep you posted on all the progress we make.