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Freya - by David Buckley Decemberr 2002

Freya is a four servo 7 inch (175mm) high biped walking robot, controlled by a PicAxe40x2.
Freya is driven by four servos and powered by four AA cells.
Freya can walk Forwads, Backwards, turn Right and Left, and Kick.
Freya can get up from any position if it falls over.
On the face and in the feet there are forward facing high power orange LEDs for illuminating obstacles which then can be detected by the black shrouded phototransitors next to them.
There are two ground contact switches on each foot for detecting table edges and whether there is secure footing.
There are two tip sensors so Freya can tell if it is tipped forwards or backwards.
Freya can play sounds and Ring-tunes from its onboard speaker.
Freya can store sixteen user inputted 16 character command strings in its memory.
There is a socket for extra memory so hundreds of commands could be stored.
Freya can be instructed by commands from a Sony IR remote-control.
The full set of instructions can be sent serially as text over cable or a plugin radio module.
Freya has an on-board command-help file.

Freya is the second in my Aesir series of four servo biped robots controlled by a PicAxe40x2, and each of them - Loki, Freya, Thor, Baldur and Ullr has a different geometry.
Originally Freya was controlled by a Parallax BS2 on an Ambler board (like Loki) but in 2014 I changed it for a PicAxe40m2 on a new board which allowed IR control from a Sony handset, and extended commands from a Serial Terminal.

The Aesir
Loki is very stable, can get up if it falls over when doing crazy moves and is a stealthy walker.
Freya amazed me, it has no trouble getting up even from lying upside down and is the best at coping with pens, pencils and other items lying on a table.
I like the way Thor stands up from sitting, and when sitting or crouching is very stable but when standing tall is easily upset and can't get up if it falls over.
Baldur is surprisingly stable and can get up from any position and can crawl and do a Roly Poly forward or backward.
Ullr is also very stable and can crawl and get up from any position and can walk sideways with ease.

Freya Software

Freya Servos

   Hip   - GWS S06, 40.6x20.0x42.8  48g, 0.33 sec 7.2kg.cm @4.8v, 8kg.cm @6v  2BB  +ve anticlockwise
   Ankle - GWSS03,  39.5x20.0x35.6  42g, 0.23 sec 3.4kg.cm @4.8v, 4kg.cm @6v       +ve anticlockwise