Strategy for Wheelchair Museum Tour

Sensors

Our cricket will be equiped with two light sensors, one taped to the front right side facing down, and the other taped to the front left side facing down. The two sensors will be plugged into the sensor A and B ports.

Initial Plans

• We will begin by starting up both motors at a low power (2-4).
• We will then program the cricket as follows using the if/then/else option in a loop.
  • If the right sensor detects white, we will turn off one of the motors so that the cricket turns right. However, if the sensor does NOT detect white, we will tell it to continue to go forward.
  • If the left sensor detects white, we will turn off one of the motors so that the cricket turns left. However, if the sensor does NOT detect white, we will tell it to continue to go forward.
• Using these commands, our cricket will (hopefully) end up moving forward while turning from side to side, looking for the white line.

Jenn, I think thats is a really good idea... and very creative too. This should definetely be our first course of action for tomorrow. But, just in case...

Jasmine's back-up plan:

We could attach one light sensor in the center of the front side pointing down so that our cricket can avoid the black area with both motors on. Although, I am not sure how the cricket will do with turns with both motors working. I think we should also take another look at the numbers that we showing up when we took the readings from the sensor. I wasn't satisfied. It seemed like the numbers were from a very large range, from like 0-200. In addition, as an attempt to solve the bonus, I say we should use one IR sensor that can maybe detect whether there is a painting in a particular spot with its "laser-like powers". And, we need to confirm if the paintings are separated by a consistent measurement. If so, maybe we can program the cricket to move x seconds along the white line before it should stop. That will make it easier to create commands for the robot; in an event that the cricket, misses a painting lets try having it move backwards instead of in a circle.

Problems/Observations

Let me just say that we had a LOT of problems!

• To start off with, the volatge of our battery was pretty low, so we replaced it with one with a higher voltage.
• Another problem we ran into was setting the power of the motors. We discovered that when we set the power higher than 4, the motors were too powerful, and so the sensors passed right over the white line without picking up a reading. We also discovered that when the power is set to below 4, the cricket does not give much repsonse.
• Another change that we made was the number that the sensor should read as white and black. At first, we told the cricket that if a sensor is less than 100, then it is on the white line. However, when we attached the display to the cricket to doublecheck those readings, we discovered that we needed to raise the value from 100 to 225. We chose 225 because if the sensor traveled even slightly off the white line the value on the display would immediatley jump up past 100. Consequently, the cricket would move off the white line even more. After much troubleshooting and playing around with different numbers, we found that 225 was the best possible value. And so, we told the cricket that if a sensor is a less than 225, then it is on the white line, and if not it is in the black.
• In addition, we definetely had to experiment with logo blocks. We learned about the loop button and that our prior blueprint had too many redundant blocks which had to be condensed.
• In short, there was a lot of trial and error involved, but in the end of it with all the mistakes that we made, we were also able to learn a good amount of inforamtion on how the cricket works. Maybe if we assigned a similar task at this point, we would not need so much time because we are now familiar with the controls, sensors, and basic make-up of a cricket.

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