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Bipede "Flatfoot"
Flatfoot is my first Bipede, but I'm sure it won't be my last. I
really like this guy.
It is very easy to build with only minimum
tools needed. Just 14 pieces of aluminium or plastic and some
screws.
The electronics are my own design. Not BEAM but logical
integrated circuits. Just imagine that you can build a "human like
walker" with so few. It is driven by two servos. I took out the
electronics and put in a H-bridge. How you can make one is seen here.
As mentioned earlier it is not BEAM.
The schematics of the
electronics you can find here.
Power is given by a 4,8 volts rechargeable battery , 250 mAh.
With a power consumption of ± 150 mA, it can walk for 1,5 hour
without recharging.
By the way, when bumping into something with one of it's feet's,
it reverses for several seconds. Some times it even turns away, just
depending on how slippery the floor is.
I think this fellow also
proves that you don't need sophisticated electronics (computers,
PIC's) to drive a robot. Compared with my Hexapod2, I like this idea
a lot. The challenge is bigger, especially when it is done without
using exotic and hard to get components.
Want to build one, just try. It isn't that difficult. You just
need some time to get it walking. Balancing is very important.
How it works? Well, with the electronics I make four signals:
1-2-3-4. With the LEDs you can follow the steps it makes.
Signal
1: Motor 1 turns "left"
Signal 2: Motor 2 turns "forward"
Signal 3: Motor 1 turns "right"
Signal 4: Motor 2 turns
"backward"
Signal 1: and so on…….
Because the signals are just time related, you need "end stops"
for the movement of the servos. In one of the pictures you can see
that the "left-right"servo has adjustable end stops.
With the
variable resistor in the electronics you can adjust the walking
speed (speed of pulses). At a certain speed you get to the resonance
frequents of the bipede. Each left-right movement is getting bigger,
and your bipede will fall on its side. Just do some experimenting,
and it will walk great. The feelers on its feet's are made bigger,
just look at the picture. They also make the bipede turn a bit when
bumping into something, so when going backward it goes in another
direction as where it came from. So simple as that, and looks really
cool.
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