Building Sensors

The following pages contain directions for building sensors for the RCX. These sensors are easy to make and useful in a classroom environment. The sensors do not cost very much and the parts can be purchased at a local Radio Shack or can be mail ordered from Digi Key or Mouser. The web addresses and 800 numbers are listed on page 55.

Warnings

· Solder contains lead.

· Do not solder if you are pregnant or breast-feeding.

· Wash your hands after soldering.

· Soldering is not harmful unless done frequently or in a small closed area.

· Follow the directions exactly, not doing so could result in a non-usable sensor.

Why build sensors?

Building your own sensors helps to understand how sensors work. It also shows students another aspect of engineering. Another reason for building sensors is the cost of LEGO® sensors. LEGO® sensors cost anywhere from $15-30 depending on which type is being purchased. Making a sensor often costs 10-20% of what LEGO® charges.

The sensor does not have to be soldered if a teacher felt the task was too messy or inappropriate for a particular grade level. Sensors can also be built using a “breadboard.” For more information about breadboards ask a lab assistant.