1. What did the robot do?
- It moved around the table and when it bumped objects it would backup a little bit and then turn and keep going.
2. What caused the robot to stop?
- it was programmed to stop when it touched something.
3. Do you think it’s a good idea for the robot to run into obstacles and stop?
- No, because the object could fall on the robot. The robot should move out of the way.
4. What are the benefits and drawbacks of this behavior?
- The benefit of using a touch sensor is that you will definitely know where the object is, but a drawback is that you could end up knocking the objet over or moving it.
5. What did the robot do?
- The robot moved around the table and stayed about 50 cm away from the walls and the objects.
6. What caused the robot to stop?
- The robot would stop when it got too close to an object.
7. How far away from the obstacle did the robot stop?
- 50 cm.
8. What are the benefits and drawbacks of this behavior?
- The benefit of using an ultrasonic sensor is you don't have to touch the object, but a drawback is that you don't know for sure if that's how far away the object is.
9. How reliable is this sensor as opposed to the touch sensor?
- It's not. The ultrasonic sensor could be a bit off and then you think something is far off when really it's rapidly approaching and then it hits your robot and kills it!
Well, the ultrasonic sensor could be better than the touch sensor because you don't affect the object, it doesn't touch, it just senses it. Like a ninja.
10. Think about the Construct Phase that you just completed and compare using the touch and ultrasonic sensors.
a. What is the main difference between the two programs?
- The touch sensor has to be right by an object while the ultrasonic sensor can be programmed to be any amount of distance away.
So I guess the difference is the distance the objects can be from the robot before the robot senses it.
b. What is the main difference in the robot’s behavior when you use each of the different sensors?
- The main difference is the time it took the robot to figure out it couldn't go in a certain direction. Using the touch sensor the robot would go until it hit the wall, but when using the ultrasonic sensor the robot was able to see that the wall was close and it changed its course.
11. The ultrasonic sensor allows you to stop before you reach an object, rather than after you’ve run into it. What are the benefits and drawbacks of this behavior?
12. The touch sensor only has two settings, pressed and not pressed. The ultrasonic sensor, on the other hand, can sense any distance between 0 and 200 centimeters.
a. Why do you need to set a threshold level for the ultrasonic sensor, but not for the touch sensor?
- Because for the ultrasonic sensor there are different distances, but with the touch sensor there is only pressed and not pressed.
b. What happens to the robot’s behavior as you change that threshold level for the ultrasonic sensor?
- If i make the threshold higher, it stays farther away from objects. And when I lower the threshold the robot gets closer to objects before it stops.
13.
a. List three reasons why you would want to use a touch sensor on a real world robot to detect obstacles.
1.) A touch sensor would be more preferable to some people because it's easier to hit something and make sure that it worked instead of waving your hand in front of an ultrasonic sensor.
2.) It would be more battery efficient than an ultrasonic sensor because it wouldn't sense when something went by it. It would have to be touched, and that would save battery life.
3.) There could be different reactions depending on if the sensor was pressed or bumped or released.
b. What kind of robots could use touch sensors in this way? Describe at least two.
- a robot kitten. I had one when I was little.
- a sink. The water dispenser on the kitchen sink. You could just touch it instead of having to lift or twist the knobs.
c. Describe at least one situation where a touch sensor could NOT be acceptably used as an obstacle detector.
- A touch sensor wouldn't work in an race because it would take too long to bump in to something and then get back on track. It would be easier to sense something with the ultrasonic sensor.
14.
a. List three reasons why you would want to use an ultrasonic sensor on a real world robot to detect obstacles.
1.) The robot wouldn't have to touch anything with the ultrasonic sensor.
2.) The robot could actually tell you how far away something is.
3.) A blind person could use an ultrasonic sensor and have a better understanding of their surroundings.
b. Does the ultrasonic sensor provide reliable detection for every type of possible obstacle.
- No. If the obstacle is slanted toward your robot, and the ultrasonic sensor picks up the bottom, the farthest part, you could end up bumping your robots head.
c. Describe at least one situation where an ultrasonic rangefinder could be acceptably used as an obstacle detector.
- If you are trying to find something but you can't physically see it. Like if you are in a boat trying to find a man eating shark beneath you in the dark abyss.
d. Describe at least one situation where an ultrasonic rangefinder cannot be acceptably used as an obstacle detector.
- If you are looking for something too small to be detected.
15. What other kinds of sensors could be used to detect obstacles, and how would you use them?
- Another sensor is a sound sensor. It detects sounds and can be programmed to speed up or slow down depending on the noise level.
16. What does the sensor show when it has difficulty detecting anything?
- ???
17. Does the shape or curvature of an object make a difference?
-Yes, depending on what area gets touched, it could be more of a distance or less of a distance away from the actual bulk of the object.
18. Does the sensor detect soft or hard objects better? Why do you think this is?
- I think the touch sensor detects hard objects better, because there's less time to squish, I guess.
19. What is the smallest object detected?
- In class? A pencil.
20. Does the sensor detect thin objects well?
- No, it won't detect it accurately if it's moving.
21. Turn the sensor 90 degrees on its side so it is positioned “upright.” Does it detect?
- Not as well as when it's the way it's supposed to be.
Thursday, October 28, 2010
Thursday, October 21, 2010
Follow That Line Part 2
1. What happened when you tried to increase the speed with the original light sensor positioning?
-The sensor worked just fine with the original position.
2. What is the reason the robot starts looping around instead of tracking the line when it tries to go too fast?
- The robot is going too fast to sense the line, so it's solution is to go in a circle, like it's programmed, until it can sense the line that it's looking for.
3. Suggest one possible way to fix the “overshooting” problem at high speeds.
-One way to fix this problem is to lower the sensor so it can have a better chance of sensing the line.
4. Where are the two turning centers located?
-The two turning centers are the wheels and the center of the robot. The wheels are located on the sides of the robot, and the center of the robot is located on Mars.
5. Why does the robot have to track in reverse after the changes?
- The light sensor needs to be in front of the robot. That is, when the robot is traveling the light sensor needs to be ahead of the rest of the robot.
6. Explain why high-speed line tracking works better with the revised configuration than the original configuration.
- When the robot is going at high-speed, the light sensor can not sense the line if it is in the back. The sensor needs to be in the front (front being in between the two big wheels) because at high speed the smaller wheels does a lot of shaking and the sensor wouldn't be able to read the line with being moved around so much.
7. Compare the performance of the old and new line trackers.
a. Build a line for the robot to track on a flat surface.
b. With the light sensor on the front of the robot and the robot moving forward, find the highest motor power that will allow the robot to successfully track the entire line. Time how long it takes (in seconds) for the robot to track the line.
c. Now switch the sensor to the back of the robot and find the highest motor power that will allow it to track the entire line backward. Measure how long it takes to track with this configuration.
c. Express the new robot’s line tracking speed as a percentage of the original (front-facing) robot’s line tracking speed. Use the formula in figure 1.
8. Identify the two main behaviors in the revised program (the two inside the switch block).
-Two main behaviors are a swing turn and the ability to sense the line.
9. Ordinarily, it’s pretty clear which side of the robot is its left, and which is its right. However, things might not be so clear when the robot is traveling backwards. Explain why, and propose a convention (a set of rules that everyone will use) for describing “left” and “right” when talking about a robot that will be line tracking part of the time, but moving normally the rest of the time.
- The NXT brick, when I'm looking at it and I can see all the buttons and the screen, that is the front. Port B is connected to the right wheel, and I can see the cord that connects it, and it is on the right side of the robot. If everyone just goes by what wheel is the right wheel and which way the brick's screen is facing there would be less confusion in the world. However, when the robot is moving that's when the front and the back get confusing.
-The sensor worked just fine with the original position.
2. What is the reason the robot starts looping around instead of tracking the line when it tries to go too fast?
- The robot is going too fast to sense the line, so it's solution is to go in a circle, like it's programmed, until it can sense the line that it's looking for.
3. Suggest one possible way to fix the “overshooting” problem at high speeds.
-One way to fix this problem is to lower the sensor so it can have a better chance of sensing the line.
4. Where are the two turning centers located?
-The two turning centers are the wheels and the center of the robot. The wheels are located on the sides of the robot, and the center of the robot is located on Mars.
5. Why does the robot have to track in reverse after the changes?
- The light sensor needs to be in front of the robot. That is, when the robot is traveling the light sensor needs to be ahead of the rest of the robot.
6. Explain why high-speed line tracking works better with the revised configuration than the original configuration.
- When the robot is going at high-speed, the light sensor can not sense the line if it is in the back. The sensor needs to be in the front (front being in between the two big wheels) because at high speed the smaller wheels does a lot of shaking and the sensor wouldn't be able to read the line with being moved around so much.
7. Compare the performance of the old and new line trackers.
a. Build a line for the robot to track on a flat surface.
b. With the light sensor on the front of the robot and the robot moving forward, find the highest motor power that will allow the robot to successfully track the entire line. Time how long it takes (in seconds) for the robot to track the line.
c. Now switch the sensor to the back of the robot and find the highest motor power that will allow it to track the entire line backward. Measure how long it takes to track with this configuration.
c. Express the new robot’s line tracking speed as a percentage of the original (front-facing) robot’s line tracking speed. Use the formula in figure 1.
8. Identify the two main behaviors in the revised program (the two inside the switch block).
-Two main behaviors are a swing turn and the ability to sense the line.
9. Ordinarily, it’s pretty clear which side of the robot is its left, and which is its right. However, things might not be so clear when the robot is traveling backwards. Explain why, and propose a convention (a set of rules that everyone will use) for describing “left” and “right” when talking about a robot that will be line tracking part of the time, but moving normally the rest of the time.
- The NXT brick, when I'm looking at it and I can see all the buttons and the screen, that is the front. Port B is connected to the right wheel, and I can see the cord that connects it, and it is on the right side of the robot. If everyone just goes by what wheel is the right wheel and which way the brick's screen is facing there would be less confusion in the world. However, when the robot is moving that's when the front and the back get confusing.
Monday, October 18, 2010
Follow That Line Assignment #4
1. What is the robot looking for?
-The robot is looking for dark and light. It will react differently
to both of them and that is how it keeps itself on the black tape.
2. Which way should it go when it sees light? Why?
-It should go right when it sees light because it is riding the left
side of the tape, and when it sees light that means that it needs to
find dark.
3. Which way should it go when it sees dark? Why?
- It should go left when it sees dark, because that is the direction
it needs to go in order to see light again.
4. My threshold value was > 40
5. Classify each of the following light sensor values as “light” or
“dark,” using the threshold value you calculated for your light
sensor.
34 :dark
78 :light
51 :light
40 :dark
6. Using your own calculated threshold, describe the motion that the
robot will make when the light sensor reads:
i. 27 : turn left until it reads light
ii. 38 : turn right until it reads dark
iii. 91 : turn right until it reads dark
iv. 45 : turn right until it reads dark
7. The line tracking behavior is built by organizing several smaller
behaviors to run at certain times. Identify two of these smaller
behaviors, and explain what they do in the program and when they are
used.
-One of the behaviors that helps run this program is a swing-turn.
When the robot all of a sudden sees light, it does an eensie-weenise
swing-turn and then when it sees dark it does another small
swing-turn.
-Another behavior is the loop. It keep my robot going back and forth
between seeing light and dark.
8. Dorothy writes this line following program one afternoon, tests it,
and finds that it tracks a line well. However, when she comes back the
next morning, it doesn’t work! She places her robot on the line and
runs the program, but to her surprise, the robot only swing-turns to
the right in a circle the whole time.
Explain what the cause of this problem is, your reasoning for why this
is the case, and what needs to be done to fix it.
- This Dorothy isn't very smart. She should know to test her
threshold every time she comes back to class and runs her robot again. See, one day she could have
a threshold of > 47, and that works well enough because for some
reason the light just falls that way on the wood table. The next day,
however, if Dorothy doesn't reset her threshold the light could be
just a bit dimmer, and so her threshold won't catch anything greater
than 47. To solve this conundrum she should just find the program on her super cool robot that measures the reflected light, and then find the threshold for dark and
the threshold for light and average the two.
9. Imagine that instead of dark tape on a light surface, your classroom
has dark surfaces with light tape on them.
a.Would the robot be able to follow the line using your same program?
-I don't think so. Hmmm, well my robot is programmed to look for
light and then go right, so if it found light and went right, well,
ya! I guess it would actually work because when it found the light it
would go right and then it would find dark and go left. So, yes. It
would work to have a dark surface with light tape.
b.Would it behave exactly the same, or slightly differently? Explain.
10. Now think about the physical placement of your light sensor on the robot.
a. Is the placement of the light sensor important?
- Yes, the placement of my light sensor is important. I don't really know why it makes the program runs more smoothly, but having the light sensor in the front is better than having it in the back. Wait, I learned this today. If the light sensor is over the little wheel it is harder to pick up a reading of light or dark because the little wheel is shaking all over the place like crazy. It's better to have the sensor in between the two big wheels, where it is stable, and easier to get a reading.
b. What happens if you raise or lower the light sensor?
- If the light sensor is raised then the robot will throw a bigger area of light and I will have to change my threshold.
c. What happens if you place it in the rear of the robot instead of the
front, but don’t change your program?
- I have my robot programmed to go right when it sees light, and if goes right when it sees light (with the sensor on the back) then it will just keep seeing light because with the sensor on the back, when the robot turns right, the sensor goes left.
11. Why does this behavior track the right side of the line instead of the left?
- The new program says to go left when it sees light, and go right when it sees dark. So pretty much it's just a backward version of the parent program.
12. When might this behavior be useful?
- If my robot is in a situation where tracking the left side of the line is impossible (like finding survivors in a collapsed building, and the left side of a black line is on fire!) It is more serviceable to track the right side of the line, and rescue the poor survivors of that collapsed building.
-The robot is looking for dark and light. It will react differently
to both of them and that is how it keeps itself on the black tape.
2. Which way should it go when it sees light? Why?
-It should go right when it sees light because it is riding the left
side of the tape, and when it sees light that means that it needs to
find dark.
3. Which way should it go when it sees dark? Why?
- It should go left when it sees dark, because that is the direction
it needs to go in order to see light again.
4. My threshold value was > 40
5. Classify each of the following light sensor values as “light” or
“dark,” using the threshold value you calculated for your light
sensor.
34 :dark
78 :light
51 :light
40 :dark
6. Using your own calculated threshold, describe the motion that the
robot will make when the light sensor reads:
i. 27 : turn left until it reads light
ii. 38 : turn right until it reads dark
iii. 91 : turn right until it reads dark
iv. 45 : turn right until it reads dark
7. The line tracking behavior is built by organizing several smaller
behaviors to run at certain times. Identify two of these smaller
behaviors, and explain what they do in the program and when they are
used.
-One of the behaviors that helps run this program is a swing-turn.
When the robot all of a sudden sees light, it does an eensie-weenise
swing-turn and then when it sees dark it does another small
swing-turn.
-Another behavior is the loop. It keep my robot going back and forth
between seeing light and dark.
8. Dorothy writes this line following program one afternoon, tests it,
and finds that it tracks a line well. However, when she comes back the
next morning, it doesn’t work! She places her robot on the line and
runs the program, but to her surprise, the robot only swing-turns to
the right in a circle the whole time.
Explain what the cause of this problem is, your reasoning for why this
is the case, and what needs to be done to fix it.
- This Dorothy isn't very smart. She should know to test her
threshold every time she comes back to class and runs her robot again. See, one day she could have
a threshold of > 47, and that works well enough because for some
reason the light just falls that way on the wood table. The next day,
however, if Dorothy doesn't reset her threshold the light could be
just a bit dimmer, and so her threshold won't catch anything greater
than 47. To solve this conundrum she should just find the program on her super cool robot that measures the reflected light, and then find the threshold for dark and
the threshold for light and average the two.
9. Imagine that instead of dark tape on a light surface, your classroom
has dark surfaces with light tape on them.
a.Would the robot be able to follow the line using your same program?
-I don't think so. Hmmm, well my robot is programmed to look for
light and then go right, so if it found light and went right, well,
ya! I guess it would actually work because when it found the light it
would go right and then it would find dark and go left. So, yes. It
would work to have a dark surface with light tape.
b.Would it behave exactly the same, or slightly differently? Explain.
10. Now think about the physical placement of your light sensor on the robot.
a. Is the placement of the light sensor important?
- Yes, the placement of my light sensor is important. I don't really know why it makes the program runs more smoothly, but having the light sensor in the front is better than having it in the back. Wait, I learned this today. If the light sensor is over the little wheel it is harder to pick up a reading of light or dark because the little wheel is shaking all over the place like crazy. It's better to have the sensor in between the two big wheels, where it is stable, and easier to get a reading.
b. What happens if you raise or lower the light sensor?
- If the light sensor is raised then the robot will throw a bigger area of light and I will have to change my threshold.
c. What happens if you place it in the rear of the robot instead of the
front, but don’t change your program?
- I have my robot programmed to go right when it sees light, and if goes right when it sees light (with the sensor on the back) then it will just keep seeing light because with the sensor on the back, when the robot turns right, the sensor goes left.
11. Why does this behavior track the right side of the line instead of the left?
- The new program says to go left when it sees light, and go right when it sees dark. So pretty much it's just a backward version of the parent program.
12. When might this behavior be useful?
- If my robot is in a situation where tracking the left side of the line is impossible (like finding survivors in a collapsed building, and the left side of a black line is on fire!) It is more serviceable to track the right side of the line, and rescue the poor survivors of that collapsed building.
Sunday, October 10, 2010
Clap-on Clap-off Assignment #3
1. Record the sound value for "quiet".
- 4%
2. Record the sound value for "loud".
- 70%
3. Record the threshold value you calculated.
- 60%
4. Write a brief description of what each block in your program does.
- The first block is the sound sensor. It recognizes the sound threshold that I programed and
- The second block is a sound sensor also. It recognizes a lower threshold than the first one.
- The third block is a motor block. It runs Port B, the right wheel.
- The fourth block is another motor block that runs Port C, the left wheel.
-The fifth block is a sound sensor block.
-The sixth block is another sound sensor.
- The seventh block is a motor block that makes Port B brake.
- The eighth block is another motor block that makes Port C brake.
5. Define the "Wait for Clap" behavior you built in the program
- The "Wait for Clap" just means that my robot has to "wait for" a "clap"before it begins doing what I programed. Clever how people name these blocks, eh?
6. What does the threshold for the sound sensor do? What would happen if you set the threshold higher? Lower?
- The threshold is like an invisible line on a hypothetical floor. If the line is crossed, it produces a result, but when things are safely staying away from the line, my robot stays immobile. If I set my threshold higher it would require more nose to trigger a response from my robot.
7. Why did you use a value from the sound sensor that was halfway between silence and clapping for your threshold value?
- I need to program my robot's sound threshold to be above the sound of silence, other wise it would go off too easily and too early. However, I had to program it a bit below my clap so that I could be sure it would respond.
8. Does your robot only respond to claps, or do other sounds trigger starting and stopping as well? Why do you think this is?
- My robot responded to other stuff, too. That's because it was only programmed to recognize a sound level, not a specific sound.
9. Mrs. Wood would like to use a robot as an actor in a class play. She wants the robot to start running across the stage on cue. The cue will be the sound of a door slamming as another (human) actor goes offstage.
a. How should she go about programming her robot to recognize the correct sound and begin its performance at the right time?
- Assuming the door slamming is the loudest part of the scene, she should program the robot to activate when the sound threshold is passed.
b. What possible problems might there be with this plan?
- Drama students can be very... dramatic. Things could get out of control and the sound threshold could be passed before it is supposed to be.
10. Someone has come up with an idea to keep order in the LLSC by turning off the lights whenever the room gets too noisy. They have a thought that a robot may be able to help them out. Explain briefly how a sound sensor-equipped robot might be able to simplify or automate this task.
- Well, first of all this is an awful idea. Have you seen what happens to classrooms when the power goes out? It's pretty much counterproductive to turn light off in a room full of loud teenagers. But if someone really thought this would help... they should take note of the noise level of "too loud" and then see the noise level of "loud, but alright". Somewhere in between "too loud" and "okay" should be the threshold where, if the noise level of "okay" is passed, the lights go out. A sound sensor should be placed somewhere in the student center to sense when the threshold is passed. When the threshold is passed and the noise becomes too loud, the lights will be triggered to go off.
11. How did the loop change the robot's behavior?
- Instead of having to press the orange button to run the program, the loop will keep the robot going on when I clap and off when I clap again.
12. How many times will the loop run?
- The loop will keep the robot going until the batteries die or class ends.
- 4%
2. Record the sound value for "loud".
- 70%
3. Record the threshold value you calculated.
- 60%
4. Write a brief description of what each block in your program does.
- The first block is the sound sensor. It recognizes the sound threshold that I programed and
- The second block is a sound sensor also. It recognizes a lower threshold than the first one.
- The third block is a motor block. It runs Port B, the right wheel.
- The fourth block is another motor block that runs Port C, the left wheel.
-The fifth block is a sound sensor block.
-The sixth block is another sound sensor.
- The seventh block is a motor block that makes Port B brake.
- The eighth block is another motor block that makes Port C brake.
5. Define the "Wait for Clap" behavior you built in the program
- The "Wait for Clap" just means that my robot has to "wait for" a "clap"before it begins doing what I programed. Clever how people name these blocks, eh?
6. What does the threshold for the sound sensor do? What would happen if you set the threshold higher? Lower?
- The threshold is like an invisible line on a hypothetical floor. If the line is crossed, it produces a result, but when things are safely staying away from the line, my robot stays immobile. If I set my threshold higher it would require more nose to trigger a response from my robot.
7. Why did you use a value from the sound sensor that was halfway between silence and clapping for your threshold value?
- I need to program my robot's sound threshold to be above the sound of silence, other wise it would go off too easily and too early. However, I had to program it a bit below my clap so that I could be sure it would respond.
8. Does your robot only respond to claps, or do other sounds trigger starting and stopping as well? Why do you think this is?
- My robot responded to other stuff, too. That's because it was only programmed to recognize a sound level, not a specific sound.
9. Mrs. Wood would like to use a robot as an actor in a class play. She wants the robot to start running across the stage on cue. The cue will be the sound of a door slamming as another (human) actor goes offstage.
a. How should she go about programming her robot to recognize the correct sound and begin its performance at the right time?
- Assuming the door slamming is the loudest part of the scene, she should program the robot to activate when the sound threshold is passed.
b. What possible problems might there be with this plan?
- Drama students can be very... dramatic. Things could get out of control and the sound threshold could be passed before it is supposed to be.
10. Someone has come up with an idea to keep order in the LLSC by turning off the lights whenever the room gets too noisy. They have a thought that a robot may be able to help them out. Explain briefly how a sound sensor-equipped robot might be able to simplify or automate this task.
- Well, first of all this is an awful idea. Have you seen what happens to classrooms when the power goes out? It's pretty much counterproductive to turn light off in a room full of loud teenagers. But if someone really thought this would help... they should take note of the noise level of "too loud" and then see the noise level of "loud, but alright". Somewhere in between "too loud" and "okay" should be the threshold where, if the noise level of "okay" is passed, the lights go out. A sound sensor should be placed somewhere in the student center to sense when the threshold is passed. When the threshold is passed and the noise becomes too loud, the lights will be triggered to go off.
11. How did the loop change the robot's behavior?
- Instead of having to press the orange button to run the program, the loop will keep the robot going on when I clap and off when I clap again.
12. How many times will the loop run?
- The loop will keep the robot going until the batteries die or class ends.
Subscribe to:
Posts (Atom)