The bottom view of JAWR bot. You can see the EOPD, wheels, and claw.
WHAT WE USE
In terms of sensors, we use a compass sensor, two EOPDs, and an ultrasonic sensor. In terms of motor use, we have a “barbaric” mechanical claw, and two large thin rubber wheels. The last thing to know about is the plastic wheels.
THE COMPASS SENSOR The compass sensor we placed up high so that it would get the least amount of magnetic interference. We also secured it very tight to get an accurate reading. We use the compass sensor to find a certain direction to turn the robot to. The difficulty with the compass sensor was that we had to set it when ever we moved to new places. However, we put a system in our program to make it so that we only had to change one variable. You can learn more if you listen to the MapDir talk. One problem with the compass sensor is that it would be nearly impossible to use just the compass sensor, because it just tells you what direction the robot is facing. That is one reason why we integrated it with the ultrasonic sensor.
THE REAR EOPD SENSOR The rear EOPD sensor is used to see the bump after we go over.
THE UNDERSIDE EOPD The underside EOPD tells us when the front wheels were at the top of the ridge. When it sees that the wheels are at the top, it tells the robot to boost over the ridge.
Click here and choose Save as “JAWRbot.L3B” locally then open in SR 3D Builder to view the complete 3D CAD model.