Saturday, December 25, 2010

Merry Christmas

Christmas is a great time for parents and kids to experience engineering with the inspiring cheerfulness of eating turkey, cakes, and looking at the fireplace while it's snowing outside. Offering the right gifts is a good way of bringing up the excitement that building artifacts can cause. While, of course, not all infants have the same thirst for scientific knowledge, for those which we find to have potential, the choice of technical gifts is not to be disregarded. While in my personal view, reminding myself as a toddler brings the memories of how vibrant and exciting it was to receive a chemistry kit, a microscope, an electronic device ready to be disassembled, etc, in the mind of a modern kid this might not be quite so satisfying. A Gormiti castle, a bunch of Ben Ten toys or any other sounding brands will certainly trigger more "processes" in a toddler's cognition.

A discussion about how today's television and toy industry affects children and youths is of little impact, but it is a fact that it is now in the hands of the parents and educators, to control the degree of exposure of their offspring to these elements, as the sole regulating factor seems to be profit generation alone.

Like with many other aspects of our world, let's hope some sense will grow out in the desert and guide those who deserve.

And of course Happy Holidays and fruitful engineering. Don't worry letting your kid become an engineer :)

Sunday, December 5, 2010

Quadrature Encoder

One of the essential things an autonomous rover must have (which mine didn't had) is one or more quadrature encoders. In fact even some non-autonomous vehicles have these devices. Most regular cars these days feature this type of sensor as part of the ABS system (see Very reliable and high-resolution sensors can be found in these (featuring 90 steps or more).

For this autonomous rover I found that 16 steps would be the bare minimum, and easy to implement with common components.

As I didn't want to modify the RC car itself (drill holes, cut parts, etc), I looked for a solution that would minimize the impact on the car. As such I found that a good option would be to use the inner ring of the wheel as a surface for sticking an encoder band. This band has 16 steps, and looks like this: