Week 3 Lab - Revision history

Rtwomey: /* force / pressure sensor */

2009-10-16T17:28:51Z

‎force / pressure sensor

Rtwomey: /* force / pressure sensor */

2009-10-16T17:27:19Z

‎force / pressure sensor

Rtwomey: /* force / pressure sensor */

2009-10-16T17:26:58Z

‎force / pressure sensor

Rtwomey: /* force / pressure sensor */

2009-10-16T17:26:48Z

‎force / pressure sensor

Rtwomey: /* force / pressure sensor */

2009-10-16T17:26:14Z

‎force / pressure sensor

Rtwomey: /* force / pressure sensor */

2009-10-16T17:26:00Z

‎force / pressure sensor

Rtwomey: /* force / pressure sensor */

2009-10-16T17:25:46Z

‎force / pressure sensor

Mchoy: /* LED Dimming */

2009-04-20T21:06:32Z

‎LED Dimming

Mchoy: /* photoresistor */

2009-04-20T21:06:12Z

‎photoresistor

Mchoy: /* Potentiometer */

2009-04-20T21:05:50Z

‎Potentiometer

@@ Line 52: / Line 52: @@
 http://www.tekscan.com/images/Flexi-response.gif
-Application circuit:
+Application circuit ([http://www.tekscan.com/flexiforce/flexiforce.html]):
 http://www.tekscan.com/images/flexi-circuit-new.jpg

@@ Line 48: / Line 48: @@
 [http://www.trossenrobotics.com/store/p/3221-1-5-Inch-Force-Sensing-Resistor-FSR-.aspx purchase]
-Voltage returned is proportional to force applied to surface.
+Voltage returned is proportional to force applied to surface:
 http://www.tekscan.com/images/Flexi-response.gif
 http://www.tekscan.com/images/flexi-circuit-new.jpg

@@ Line 44: / Line 44: @@
 [[Image:FSR.JPG|300px]]
 [http://www.trossenrobotics.com/images/productdownloads/FSR%20data.pdf datasheet]
 [http://www.trossenrobotics.com/store/p/3221-1-5-Inch-Force-Sensing-Resistor-FSR-.aspx purchase]

@@ Line 44: / Line 44: @@
 [[Image:FSR.JPG|300px]]
-Voltage returned is proportional to force applied to surface. [http://www.trossenrobotics.com/images/productdownloads/FSR%20data.pdf datasheet]
+Voltage returned is proportional to force applied to surface.
-[http://www.trossenrobotics.com/store/p/3221-1-5-Inch-Force-Sensing-Resistor-FSR-.aspx purchase]
 http://www.tekscan.com/images/flexi-circuit-new.jpg

@@ Line 47: / Line 47: @@
 Voltage returned is proportional to force applied to surface. [http://www.trossenrobotics.com/images/productdownloads/FSR%20data.pdf datasheet]
 [http://www.trossenrobotics.com/store/p/3221-1-5-Inch-Force-Sensing-Resistor-FSR-.aspx purchase]
 http://www.tekscan.com/images/flexi-circuit-new.jpg

@@ Line 97: / Line 97: @@
 * Q: Drive this dimming example with the light sensor from before.
 ** use <code>analogRead()</code> to get the value from the sensor, like you did before, then use <code>analogWrite()</code> to output the value to the LED.  NOTE: <code>analogRead()</code> will return values from 0-1023, and <code>analogWrite()</code> writes values from 0 to 255, so you will need to divide your read value by 4 to get the output value.  Or you could use <code>map()</code>
-* Q: Does yours turn on when it is light, or does it turn off?  Switch this to give it the opposite behavior, in either hardware or software.  You could do either!
+* Q3.1: Does yours turn on when it is light, or does it turn off?  Switch this to give it the opposite behavior, in either hardware or software.  You could do either!
 === Lightbulb ===

@@ Line 22: / Line 22: @@
 Take the photoresistor from your 147A kit, which has a resistance between 140k - 800 depending on your lighting conditions.
-*Q: With the same R2 resistor (10k) from above, replacing R1 with the photoresistor, what range of voltages (and corresponding data values) would you expect to see at your A_IN pin?
+*Q2.1: With the same R2 resistor (10k) from above, replacing R1 with the photoresistor, what range of voltages (and corresponding data values) would you expect to see at your A_IN pin?
-*Q:  The important part of this sketch is the line where the microprocessor reads the analog input:<code>   val = analogRead(potPin);</code> Looking at the Arduino help for that function (<code>analogRead()</code>), what do you think the value <code>val</code> will be for those highest and lowest voltages at your A_IN pin?
+*Q2.2:  The important part of this sketch is the line where the microprocessor reads the analog input:<code>   val = analogRead(potPin);</code> Looking at the Arduino help for that function (<code>analogRead()</code>), what do you think the value <code>val</code> will be for those highest and lowest voltages at your A_IN pin?
-*Q: How can you verify your guess for the previous question?  Come up with a plausible method, and try it out.  Anything goes!  (even using functions next weeks material, like Sketchbook->Communication->Graph) If you have a good idea, share it with the class....
+*Q2.3: How can you verify your guess for the previous question?  Come up with a plausible method, and try it out.  Anything goes!  (even using functions next weeks material, like Sketchbook->Communication->Graph) If you have a good idea, share it with the class....
-* Q: How could you make this more sensitive? There are least three ways to try... think in terms of the physical enclosure around the sensor, the hardware setup (a voltage divider), and the software (look at File->Sketchbook->Analog->Calibration..., specifically the <code>map()</code> function)
+* Q2.4: How could you make this more sensitive? There are least three ways to try... think in terms of the physical enclosure around the sensor, the hardware setup (a voltage divider), and the software (look at File->Sketchbook->Analog->Calibration..., specifically the <code>map()</code> function)
-* Q: Does changing the code make this more sensitive?
+* Q2.5: Does changing the code make this more sensitive?
 === FYI other sensors ===

@@ Line 13: / Line 13: @@
 [[Image:Pot_photo.JPG|400px]]
-*Q1: What will the voltage at A_IN be?  What are the upper and lower values? (HINT: it is a voltage divider.  How do you calculate the voltage in a voltage divider?)
+*Q1.1: What will the voltage at A_IN be?  What are the upper and lower values? (HINT: it is a voltage divider.  How do you calculate the voltage in a voltage divider?)
 === photoresistor  ===