Mapping with your Robot

What is mapping?

• The process of using a sensor to determine the location of objects or holes in a remote area

What is mapping?

• Mapping can be done with satellite images, sonar, radar, etc.

Why map?

• July 2002, nine miners dug through a wall into another tunnel

• The other tunnel was filled with groundwater, which trapped them in a tiny air pocket

• The other tunnel was part of an abandoned mine that had filled with groundwater

If the miners had stopped excavating earlier, this could have been avoided.

Why didn’t they stop when they got too close?

Why map?

• They didn’t have an accurate map of the abandoned mine to know when they would hit it

• They were rescued after 77 hours, but it could happen again

Why robots?

• Abandoned mines fill with groundwater• Groundwater mixes with dust leftover from

mining to produce toxic, slippery sludge• Support timbers rot, leaving the mine

structurally unstable

Why robots?

• This is a dirty, dangerous job!

• Robots can map just as well as humans

• Robots don’t complain

• This method won’t endanger human life

Mapping with Ultrasonic Sensor

• Ultrasonic sensor works by bouncing sound waves off of an object

• We cannot heard ultrasonic noise

Mapping with Ultrasonic Sensor

• Records how quickly the waves bounce back

Mapping with Ultrasonic Sensor

• That tells it how close or far an object is

• The farther it is, the longer it takes for the waves to bounce back

Mapping with Ultrasonic Sensor

• We can measure the area first and compare measurement to the sensor readings

• Shows us how accurate the sensor is

Bluetooth Technology

• Every NXT is equipped with Bluetooth technology

• Allows it to send information to anything else that has Bluetooth

NXT to NXT Communication

• NXT can send data to any other NXT using Bluetooth

• Will be using one NXT to map and send data, another to receive data

Project Goals

• Prototype that can take accurate measurements of interior of model mineshaft

• Organized group structure, well-defined individual tasks

• Presentation of your prototype and your work