Obstacle Detection

1. The robot went forward until it ran into the wall and stopped.
2. The touch sensor felt the wall and told the robot to stop.
3. No. The robot could bump into a fragile item and break it. Running into things all the time could ruin the robot as well. It is better than running into something and trying to keep going.
4. The robot is able to sense where things are, but it can only do that by running into them.
5. The robot ran until it sensed the wall and stopped a couple inches from it.
6. It sensed the wall because of the radar, which told the robot to stop.
7. The robot stopped about four centimeters from the wall, measuring from the front of the sensor.
8. The robot will stop when it sees obstacles and will not run into them, but it may not see the smaller objects.
9. It is not as reliable as the touch sensor because it is unable to sense smaller obstacles. However, it is good if you want to avoid something without running into it first.
10.
i. We changed the wait for block from touch sensor to ultrasonic sensor. The touch sensor senses where things are by running into them and the ultrasonic sensor senses where things are by bouncing radar waves off of them.
ii. One stops after it runs into an obstacle, and the other stops right before it runs into something.
11. The robot will stop when it sees obstacles and will not run into them, but it may not see the smaller objects.
12.
i. The ultrasonic sensor depends on a variety of variables, like the light sensor and the sound sensor, so you need to set a threshold so the robot knows how far to look ahead. It also has a range that it can detect, so you need to set it to how far you want it to look ahead.
ii. If the threshold is changed, the robot will stop closer or farther away from the obstacle.
13.
i. to detect walls
   to navigate a maze
   to  determine exactly where obstacles are
   the sensor is easier to use
ii. robots that are trying to navigate on their own and robots going through a maze. Scales and computer mice are also touch sensors
iii. It would not be acceptable when the obstacle is fragile or if it in a small area.
14.
i. so you don't run into things
   more efficient  and easy to program
   to detect from far away where an object is
   to map out an area
ii. No. It cannot see some smaller objects.
iii. A robotically-driven tractor navigating a field
iv. If the robot is traveling over bumpy terrain with small rocks, it may not be able to see them.
15. The touch sensor can detect obstacles by feeling when the robot runs into something. The light sensor can detect obstacles by looking for the shadow of an object. A thermal detector or infrared sensors could detect humans or animals in the area. Magnets could detect the distance, like a metal detector.
16. ??????
17. Yes.
18. It detects hard objects easier because it is more rigid and bounce the waves back easily.
19. The smallest object detected was the ruler.
20. No.
21. Yes. The thinner objects can be seen easier by the sensor.