Today, i had my second programming class with 11th grade student, scientific option. Everything went well, and in less than 1 hour, they had coded multiple algorithms to the robot : obstacle avoidance with the contact switches, and then scanning ahead with the servo mounted front sensor.

As i have not done the cover yet, for those two sessions, they used it without it. From this, i learnt a few things.

• As is, without the cover, the robot is not easy to catch while running. Indeed, the easiest place to grab it is the wheels. However, as they are moving, it's probably not great for those small servos;
• the main switch cuts the power from the battery, thus disabling everything, which is good. however, when plugged in USB, the USB powers the servos, and they move. I'll need to either move the switch, add a second one, or add a diode;
• if using only the contact sensors, the robot can get stuck on a chair foot if it hits between the sensors. It works well with walls through;
• the wheels are slightly wider than the contact switch lever. It is thus possible for an obstacle to miss the switch lever, but hit the wheel. A good body design should protect the wheels however.

I will thus be improving this design in the next weeks to solve those issues.

About the students : they are 11th graders from Guadeloupe (a french west indies island), and have no programming class at school. I go there once a week, for an hour, and bring robots for them to program and learn programming. It's not an official class, i'm not paid for this or anything. However, next year, i'll use this robot for my computer science class.