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First I tried to apply my work in NOC to the basic idea of the free body diagram Forces
Then I found that this applet works better
But I’m still not sure about how apply this to a more complex mechanism.
Links:
http://hyperphysics.phy-astr.gsu.edu/hbase/N2st.html#c1
http://www.glenbrook.k12.il.us/gbssci/phys/CLass/newtlaws/u2l2c.html#8
My first approach to build a gear mechanism was to try to design a basic system that could be made using Autocad and lasser cutting
Then I realized that for the kind of movement that I want, where the gear changes the direction of a turning movement, I needed a bevel gear, and that was to complex for my first drawing/models.
Finally I’m using the paper bevel gear from the Flying Pig toy as a model to develop a gear system that allow me to produce basic mechanism based in model made in cardboard.
ADXL 320 Accelerometer
Translational-motion inertial sensor.
Data sheet
An accelerometer output is a variable voltage depending on the amount of acceleration applied. The common reference is the resultant acceleration produce by earth’s gravity force. The unit used for the acceleration measure is g, the earth’s gravity at sea level. (1g = 9.8 m/s~2)
Their outputs need to be integrated once with respect to time to get velocity and integrated twice to get position (?)
Uses:
Inertial measurement of velocity (position)
Sensor of inclination, tilt or orientation
Vibration or impact sensor
Type:
Differential capacitive
Output a voltage dependant on the distance between two planar surfaces. One of the surface are charged with electrical current, the change in the gap between the plates changes the electrical capacity or the system.
Specifications:
Number of axes: 3 axis
Senor Input: ±3 to ±3.6 g
Sensitivity: 270 – 330 mV/g
(Voltage output per g)An indicator of the amount of change in output signal for a given change in acceleration expressed in terms of volt per unit of acceleration.
Is the Ratio of an electrical output to the mechanical input. RADIOMETRIC
Amplitude stability:
Changes in sensitivity in temperature or time
Zero g offset: 1.2 –1.8 V
(Voltage output at 0 g) It is specified for the position of the sensor where is active axis is perpendicular to Earth’s gravity.
Frequency response:
It is the output signal over a range of frequencies where the sensor should operate.
Bandwidth: X and Y = 1600 Hz Z= 550Hz
Indicate how often a reliable reading can be taken. (Hundreds of hertz for vibration)
The bandwidth determines the measurement resolution.(smallest detectable acceleration)
Output amplifier: Low 0.1 V – High 2.8 V
(Maximum and minimum swing)
Power Supply: 2- 3.6 V
Power consumption
Temperature range: -25 to 70 °C
With a 0.1 uF Capacitor placed close to de sensor supply pin is possible to reduce noise from the power supply.
More capacitors can be added to implement low-pass filtering for antialiasing and noise reduction.
For my Midterm exercise I want to keep working in a project that I build for my phycomp class last term. The project “Paint bucket tool” is a processing application that uses the data of a 3 axis accelerometer to map a spiral in which the changes of velocity in the Z axis of the Object place circles in a spiral, and the position, color and scale of these circles are determined by the change of the velocity in the 3 axis. The result is a kind of drawing tool with a splash effect, that I want to improve to get a better visual response to the gesture of the shaking object.
For the Time and sensor assignment I decided keep working with the ADXL3xx 3 axis accelerometer. I’ve tried to build a visualization for this accelerometer before, but without an average or standard derivation.
For the standard derivation version I base mi code In Daniel Solis exercise.
For my exercise I’m going to present a work that It’s more related with the concept of performance from the Golan Levin’s work. I would like to keep working with exercise that I start developed for my ICM class last term, in which I use a simple color tracking in order to control the playback of a video with the manipulation of color objects in front of the camera. In that previous exercise I work in Processing, and that allow me to have acceptable color tracking but couldn’t handle the video playback interaction. Now I want to try with Max and jitter and I haven’t decided yet if I going to work with color tracking or I’m going to use an element of sound to manipulate the video.