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motors commercially available do not normally have a desirable speed to torque ratio (the main exception being servos and high torque motors with built in gearboxes)

With gears, you will exchange the high velocity with a better torque.

the larger gear will move more slowly than the smaller gear, but it will move with more torque.

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.

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.

Pleo Technical Specs: Ugobe LifeOS 32 bit Atmel ARM 7 microprocessor - The main processor for Pleo 16 bit sub processor - The processor dedicated to the camera system (4) 8 bit processors that provide the low-level motor control for the servos (35) Sensors including a camera custom designed to fit into Pleo’s very compact body. (4) foot-switches to detect footfalls and being picked up - assists with spatial orientation. (12) capacitive touch sensors (4) legs, (4) feet, back, shoulder, head, chin (2) microphones for directional sound detection (14) “Force” sensors, one per servo, to recognize abuse through force feedback joints. Orientation/tilt sensor IR transceiver for bidirectional data communication with other Pleos. IR interrupter for detection of objects in Pleo’s mouth (14) motors. Standard low voltage DC motors (150) gears and clutches Rechargeable NiMH battery pack USB port with mini USB connector SD/MMC memory card slot

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.