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    Final Project – The Helper


    2009 - 12.18

    The helper is an assistive technology for a person with muscular dystrophy who can not pinch. It is composed of an arm and a controller. The controller is composed of 2 round objects the control the arm sided to side and around itself.  The controller has 2 buttons one to open and close the grabber and a preset button that will bring the arm to bring object to the user.

    This is The Helper

    For the controller we used bowls because they would be easier to rotate with the palm of your hand.

    We used big buttons to make it easier for the user who lack dexterity to push them.

    The helper is controlled by two 360 potentiometer and two lighted big buttons.

    Russ started with a cardboard mock up of how the grabber will operate.

    Parts are in for the Grabber and Servo for the Arm.

    The original design for the grabber the gears went on the outside, then mount for gear, then the axel. This did not let the axel spin 360 degrees.

    We kept the main box clear any obstructions down to the rivets in order to have smooth movement for the Grabber.

    This is the interim design that the grabber had. We mounted the axel on the inside which let the axel rotate 360 degrees.

    This is the side view of the interim design for the grabber.

    The required torque power for mounting to the rear of the Grabber was to great for our servo. We cut down the lifting force by mounting the arm closer to the center of the Grabber box.

    In order for us to mount the arm in the center, we had to redesign the Grabber box to include a roof.

    One stumbling block that we found was the Grabber was binding if drove it from only one side. We had to run a drive shaft to the other side so that they wheels rotated equally.

    Quick test to see if the servo can lift the Grabber from it's new mounting point.

    Originally we mounted the arm directly to servo. This put to much stress on center screw on the servo and flexed to much.

    Pcomp Final – The Helper from Zeven Rodriguez on Vimeo.

    Media Controller Midterm – Documentation


    2009 - 11.30

    For the midterm in Physical Computing our group created a media controller that would allow a user to control the various everyday sounds of New York City.   We spent many meeting brainstorming about how the user will control these sounds.  We finally decide to use individuals pods to control the volume of different sounds discretely.  We broke up the project into the following task:

    1. Record the sound of New York City and edit them
    2. Construct and wire the pods
    3. Programming for both the Arduino and Processing application

    Subway RecordingsThe first thing we did was to go around New York City recording different sounds with a boom unidirectional microphone and a digital audio recorder.  We went from the village to Time Square recording construction sounds, ATM beeps, people walking, conversations, fire trucks, musicians at the subway stations, and water at the piers.  We then edited the sounds into seamless loops.  Having the loops be seamless will allow us to keep the sound files small and also have the sound replay seamlessly creating a rewarding experience for the user.

    Our next task was to find a suitable pod that would represent the urban feel of New York City.  We found these metal food containers that fit our idea of what they should look like.  All the circuits and wires fitted perfectly inside the pods.

    P1000701

    The last task to our project was creating the serial communication between the the Arduino board and Processing, as well as programming the logic for how the user with use the pods.  We used accelerometers for sensing the gestures of the user.  I found that it was hard to read the gestures of a person over the noise of the sensors and the environment.  The resolve of this issue was gestures that were abrupt and jerky.  We were initially thinking the gesture for controlling the volume of the sound would be like a conductor waving their wand.  We tried to do the same but the gesture were very hard to trigger the volume up and down of each sound.  I was able to refine the code to allow for a more gentler gesture for controlling the volume.  The result is a much easier and pleasant experience for the user.

    IMG_3827

    We used the Minim library in Processing to control the different sounds.  We have all the sounds playing at a low initial volume.  The user will then shake a pod to increase a sounds volume.  Then can then either turn the pod upside down or suddenly drop the pod in there hand to volume down.  We have one 3-axis accelerometer and one Super Bright white LED in each pod.  The pods are wired to a Arduino Mega board.  We are using a Arduino Mega because the Duemilanove did not have enough analog pins.  We initially  wanted to have 8 pods but due to a bug in the Mega firmware we could not use 8 pods.  Instead we used 4 pods for our presentation.  We wanted to use the LED’s in each pod to indicate the volume level of that sound.  We ran out of time to implement this feature.  Instead we have the LED’s blinking.

    I am satisfied with the outcome with this project.  I learned a lot about how to filter the noise out of the accelerometer sensors.  The final behavior for controlling the sounds is acceptable.  I would like to spend more time in refining the gestures for controlling the sounds if I were to continue working on this project.

    Week 10 – Final Project Concept


    2009 - 11.17

    The helper is an assistive technology for a person with muscular dystrophy who can not pinch. It is composed of an arm and a controller. The controller is composed of 2 round objects the control the arm sided to side and around itself.  The controller has 2 buttons one to open and close the grabber and a preset button that will bring the arm to bring object to the user.

    eHelper

    Week 8 – Midterm Media Controller


    2009 - 11.04

    For my midterm project we were asked to create a media controller. My group choose to controller New York City ambient sounds.  We began our project by recording everyday sounds that one would hear in New York City.  Our controller consists of pods that control the volume level of individual sounds. The volume level is increased by shaking the pod and decreased by suddenly moving the pod downwards.

    See the video: