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"Exposing a Flaw: Shoot-Through" describes the serious problem with that circuit, especially when pulsed

Above is an improved version of the circuit, which is now PWM compatible. PWM, coast mode, and the capability to avoid shoot-through are provided by adding a fifth MOSFET (labeled Q5) to the source/ground connections of Q1 and Q3.

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.

camera-based vision system (for light detection and navigation) two microphones, binaural hearing beat detection (allows pleo to dance and listen to music) - this feature was removed but may be added on again. eight touch sensors (head, chin, shoulders, back, feet) four foot switches (surface detection) fourteen force-feedback sensors, one per joint orientation tilt sensor for body position infrared mouth sensor for object detection into mouth infrared transmit and receive for communication with other Pleos Mini-USB port for online downloads SD card slot for Pleo add-ons infrared detection for external objects 32-bit Atmel ARM 7 microprocessor (main processor for Pleo) 32-bit NXP ARM 7 sub processor (camera system, audio input dedicated processor) four 8-bit processors (low-level motor control)

The current through a photodiode is directly proportional to the light intensity

The photodiode and phototransistor can be both photovoltaic (generators of potential difference) and photoconductive (modifiers of an electric current), depending on the application.

A reverse-biased photodiode operates in what is called photoconductive mode, since the conduction of the semiconductor junction varies with the illuminating light intensity.  If the reverse-biased voltage is relatively large (i.e. several volts) the reverse-biased photodiode will have a very fast response time (much faster than an LDR) and is suitable for detecting light signals that vary down to a time scale of a fraction of a microsecond.

stimulus-response

a plan of action

combine the best of both Reactive and Deliberative control

This simple circuit can detect the invisible fields of voltage which surround all electrified objects

One essential difference is that the Nv responds immediately to an input, and sends the output for a time duration -- the delay occurs AFTER the output is sent. The Nu responds to an input after a delay and sends the output continuously -- the delay occurs BEFORE the output is sent.

"on" first, then a delay, then "off"

delay, then "on", stays "on"

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.

Reverse bias induces only little current (known as saturation or back current) along its direction. But a more important effect of reverse bias is widening of the depletion layer (therefore expanding the reaction volume) and strengthening the photocurrent. Circuits based on this effect are more sensitive to light than ones based on the photovoltaic effect and also tend to have lower capacitance, which improves the speed of their time response. On the other hand, the photovoltaic mode tends to exhibit less electronic noise.

Photodiodes can be used under either zero bias (photovoltaic mode) or reverse bias (photoconductive mode)

Many Logo-based and other robotics products produced by LEGO are distributed to schools in the USA by Pitsco.

This free-range turtle does not require connection to a computer. All the controls are on board.

The Cricket is a tiny computer, suitable for all kinds of robotics projects, that you can program using Logo.

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

By just tying a neuron's bias resistor to Vcc, rather than to ground, you can make a "regular logic" (active high) Nv:

putting diodes and other resistors in parallel to give different charge vs. discharge rates

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1381s are CMOS voltage-controlled triggers -- these "gate" a source until the voltage is above some "trip" limit, at which point it is allowed onto a third pin.

If you can't find 1381s locally, you might have better luck finding its European cousin, the TC-54 -- for details on it, see its data sheet.

To use a photodiode in its photoconductive mode, the photodiode is reverse-biased; the photodiode will then allow a current to flow when it is illuminated.

LEDs can be used as photodiodes

FLEDs are light-sensitive, and so flash faster in brighter light