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All Cricket devices have a built-in bidirectional infrared communications channel, which is used for Cricket-to-desktop communication (when downloading programs to a Cricket, or viewing sensor data) and Cricket-to-Cricket communication.

Cricket Logo is based on an iterative, interactive model of project development. It includes a “command center” window; instructions typed into this window are instantaneously compiled, downloaded to a Cricket, and executed, giving the system the flavor of an interpreted software environment such as LISP, BASIC, or FORTH.

The MetaCricket software system is based on a virtual machine, written in PIC assembly language and running on the Cricket, and a compiler for the virtual machine running on a desktop development computer

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.

attach your Pager Motors to your Popper using two Fuse Clips, two Small Paper Clips, and no solder

The purpose of a solar engine is to act like a power "savings account" -- a small trickle of incoming energy is saved up until a useable amount is stored

A solar-powered robot can be made to work, even in relatively-low light levels

Solar cell size is minimized

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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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"

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

We use them as 3- or 5-volt triggers

This chip is often considered the heart of Nv net technology

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 !

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.

I wanted to share an adaptation of the Schead v4, that I have been experimenting with. It is (for lack of a better term) a Master/Slave Schmitt Comparitor Head (M/S SC-H). With the addition of a 74 AC 240 or two (as motor drivers) and a pair of motors, you can put together an interesting little light seeking, wheeled robot with peripheral vision.

As long as the light reaching the photo-bridge of the Master SC-H is balanced, then the Slave SC-H acts as a regular, lone SC-H would. So, if one of the slave photo-diodes detects more light then the other, the inverter that controls the motor on that side changes states and is now the same as the inverter of the Master SC-H tied to the same motor. This turns that motor off and the robot will pivot around the stopped wheel toward the greater light source until the light on each sensors is balanced and the motor again begins to turn.

I am also using SCar to continue experimenting with Stacking separate Sensor/Behavior circuits onto a robot. I will post more as progress is made.

Droidmakr (Cliff Boerema) came up with an interesting idea for a light-tracking head with a form of peripheral vision. As often happens, the circuit turned into something different -- a photopopper:

All done with a single 74HC14 (the '240 being a motor driver).

I tried the same setup with the 74*240 (with an extra inverter per motor) and 7404, but the 74HC14 seems to work best.

This adapted photodiode is not as sensitive as large area types so C2 may need to be reduced to 0.01uF while the value of R2 and R3 can be increased by a factor of 10.

Two leaded phototransistors can also be used but may require extra shielding to reduce light current in the bridge to acceptable levels

basic photopopper functions plus reverse -- all on a single chip

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.

三十年的计算机视觉的历程表明，1 MIPS的机器能从实时图像中提取简单的特征量───在杂色背景里跟踪白线或白点。10 MIPS的机器能跟随复杂的灰度区，巡航导弹、灵巧炸弹和早期的自驾驶大蓬车证实了这点。100 MIPS的机器恰好能追踪路面上不可预测的特征量，Navlab在长距离的行程证实了这点。1000 MIPS的机器完全能识别三维空间中带纹理的粗糙物体，某些中分辨率的立体视觉程序解释了这个问题，也包括我的程序。几个“垃圾箱挖掘”程序认为，10000 MIPS的机器能从杂乱中找到三维物体，并且高分辨率的立体视觉程序用10 MIPS的机器在1小时内演示了这一点。随着计算机速度和内存的增大，数据量问题逐渐不再是问题。

除了纯粹的运算规模，也得考虑其他因素。对1 MIPS的机器，最适用的程序是能有效处理检测数据的手工程序。

机器人视觉程序想要聪相应图像中得到一个边缘检测或移动检测数据的话，需执行100条计算机指令。一百万次检测则对应执行一亿条指令，1000MIPS的机器1秒能重复十次上述过程，基本上可与人的视网膜相比，新型高端个人计算机刚好能达到这个性能。

三十年的计算机视觉的历程表明，1 MIPS的机器能从实时图像中提取简单的特征量───在杂色背景里跟踪白线或白点。10 MIPS的机器能跟随复杂的灰度区，巡航导弹、灵巧炸弹和早期的自驾驶大蓬车证实了这点。100 MIPS的机器恰好能追踪路面上不可预测的特征量，Navlab在长距离的行程证实了这点。1000 MIPS的机器完全能识别三维空间中带纹理的粗糙物体，某些中分辨率的立体视觉程序解释了这个问题，也包括我的程序。几个“垃圾箱挖掘”程序认为，10000 MIPS的机器能从杂乱中找到三维物体，并且高分辨率的立体视觉程序用10 MIPS的机器在1小时内演示了这一点。随着计算机速度和内存的增大，数据量问题逐渐不再是问题。

除了纯粹的运算规模，也得考虑其他因素。对1 MIPS的机器，最适用的程序是能有效处理检测数据的手工程序。　　100 MIPS的机器能权衡输入数据，有很多算法参数待定，采用学习算法要比程序员调节效果好。

机器人视觉程序想要聪相应图像中得到一个边缘检测或移动检测数据的话，需执行100条计算机指令。一百万次检测则对应执行一亿条指令，1000MIPS的机器1秒能重复十次上述过程，基本上可与人的视网膜相比，新型高端个人计算机刚好能达到这个性能。

Note that the resistor value of the pull-down resistor affects the voltage at pin 3 of the Furby's connector. We used a 1k ohm resistor to make it less sensitive to light (since we're now operating with it open to ambient light).

In the above diagram, a 20k ohm resistor is used as the pull-up resistor. You can, however, use any resistor as the pull-up resistor as long as the resistance is high enough to protect the circuit.

Note that behaviors themselves can have state, and can form representations when networked together. Thus, unlike reactive systems, behavior-based systems are not limited in their expressive and learning capabilities.

The basis behavior set of a system provides elements that are not further reducible to each other and that, when composed by sequential or concurrent execution, produce the complete behavior repertoire for the system.

Such basis behaviors are constructed, learned, or evolved from stable, robust interaction dynamics between the agent/robot and its environment, and serve as a substrate for the system's more complex behaviors.

My work generalized the notion of basis behaviors to multi-robot interactions, and demonstrated how a small set of basis behaviors per robot can be used to demonstrate a rich repertoire of individual and group-level behaviors, including following, flocking, homing, herding, aggregation, dispersion, and formations.