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These bots are powered by a Gold Cap and for a period of about one minute they move, always looking for the brightest lightspot, so in fact they will even follow a lightsource.

All these bots are powered by a 3,3F Gold Cap ( F= farad). You can charge them with a regulated power supply

the two 5 mm red LED's it is capable of following a light source.

The Sharp IR Range Finder works by the process of triangulation. A pulse of light (wavelength range of 850nm +/-70nm) is emitted and then reflected back (or not reflected at all). When the light returns it comes back at an angle that is dependent on the distance of the reflecting object. Triangulation works by detecting this reflected beam angle - by knowing the angle, distance can then be determined.

The IR range finder reciever has a special precision lens that transmits the reflected light onto an enclosed linear CCD array based on the triangulation angle.

The Sharp IR has a non-linear output. This means that as the distance increases linearly (by set increments), the analog output increases/decreases non-linearly.

CALEB CHUNG: Of course we could have used micro-servo motors to accomplish the motion of Pleo, but we aren’t able to use expensive motors. So we had to engineer it with a high-speed motor with high gearing and no backlash for control purposes and have it all fit within the muscle envelope of Pleo.

So what we did was go after a lot of ethology research. How do animals really handle the complexity of their environment? We built a virtual brain—a whole system that decides how Pleo will react in various situations.

CALEB CHUNG: Pleo will reset thresholds and adjust his idea of what he thinks is normal. Let’s say you get Pleo and you take him home to your shag carpet. When Pleo walks, the carpet will drag on his feet. So his force feedback sensors will realize that he is spending too much energy to walk around. Pleo will try different things to reduce the energy spent. Eventually, he will have the idea to step higher. Your Pleo compared to my Pleo will walk with a higher step.

how to interpret sensor data into a mathematical form readable by computers

There are only 3 steps you need to follow: Gather Sensor Data (data logging) Graph Sensor Data Generate Line Equation

Some sensors (such as sonar and Sharp IR) do not work properly at very close range

It is powered with two 3.3F Goldcaps. They can be charged in a few seconds. When they are charged, MAXIBUg gets "afraid" of light, and wanders of to go to play "in the dark". After a while, about 20 seconds (depending on the current used by the two motors ), the power has dropped, and it wants to "eat". It gets light attracted, and will turn and go to the light. When it gets there, it will recharge and still will be atrackted to the light until it reaches a trigger voltage , at which it gets "afraid"of the light again. This will go on all day until someone turns off the lightsource. While doing all this it also will backup when bumping into something.

Because of the "on-off" output of the first schmitt trigger, the inputs for the LDRs will switch. That's why it gets light atracted -light afraid. This also means that you cannot use IR diodes (like SHF205). You have to use LDRs !

All of the procedures take a discrete ``gear'' to specify the speed. The reasons for this are two-fold; first, by limiting the power of the truck, we simplify the interface to children. Secondly, it allows use to calibrate the ``gears'' so that, for example, 10 seconds forward in first gear is the same distance as 10 seconds backward in first gear.

The limitation of LOGO however is the lack of feedback from the environment. There is no way of expressing an event occuring in the outside world.

Simple constructs in iLogo extend the original LOGO language with interactivity capabilities of reading sensors and transfering control to different parts of the program.

Motorcycle lead acid batteries work great for larger low performance type robots. They are great for solar power robots too.

lead acid batteries have the serious problem of being very large and heavy, need to always be kept charged, and do not have the high discharge rates as the more modern batteries.

They have low power capacities, are heavy, have trouble supplying large amounts of current in short time periods, and get expensive to constantly replace

This is the 3 capacitor method.  I used this one in all my RC cars and many of the RC toys that I have taken apart use this method.

One of the easiest and most overlooked technique that can be done to lower motor noise is the twist your motor and motor power wires.  This in affect forces the magnetic fields to cancel each other out.

By placing a metal shield between your motors and radio can do wonders.  Also keep in mind that some metals shield better than others.   Carbon Steel shields several hundred times better than aluminum.  Dont use this shielding as a conductor or you may compound the problem.

Most BEAMbot designs require at least 3 volts from their solar cell(s). This means, of course, that if you buy 0.5 V cells, you need to wire together at least six of them to do the job. This may or may not be something you want to mess with; it may or may not fit with the aesthetic design you're shooting for.

Large diameter wheels give your robot low torque but high velocity. So if you already have a very strong motor, then you can use wheels with larger diameters.

But if your motor is weak (such as if it does not have any gearing), you want to use a much smaller diameter wheel. This will make your robot slower, but at least it has enough torque to go up a hill!

Wheel width. You do not want it too wide as it causes increased resistance to rotating the wheel on a surface.

The robots do not build a model of their world they simply act in response to the things they encounter whilst existing there.

This form of robotics has proved to be successful in environments that are unknown to the robot, environments that are busy or noisy such as a place with moving objects or people

An important part of the behaviour based theory is "embodiment" This means that a robot must be embodied, have a presence (it is an entity in itself).  In order to react the robot must be surrounded by the real world.

We assume that the slowly changing waveform at the Nv input produces a single output transition when it crosses the Nv switching threshold. This is accomplished by using a 74HC14 or similar CMOS Schmitt trigger. When 74HC04 or 74HC240s are used for Nv inverters some nasty oscillations occur during switching which makes these inverters unsuitable for most Nv networks greater than 2 Nv in series.