Omni-directional QUADRUPED ROBOT - VIDEOS?

Lynxmotion Legged Robots
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** Body**

The body is a 30x30x31-centimetre octagonal structure containing all the power and control electronics. The SILO4 legs are placed around the body in a circular configuration in order to enhance the Omni-directional capabilities and manoeuvrability of the vehicle. The robot’s structure is mostly made of aluminium and its total weight is about 30 kilograms.

** Legs**

The legs of the robot are based on an insect-type configuration. Each leg is composed of three links connected by rotary joints. All the joints are powered by DC motors with incremental encoders housed on each link. Motion transmission is done via a planetary gearbox. Joints 2 and 3 are also driven via an irreversible gear in order to reduce power consumption, as these joints support the entire body weight.

Feet

The SILO4 foot is connected to the third link by means of three passive joints, which enable adequate contact between the sole and the ground. The angle between the sole and the third link can be measured by two potentiometers. A three-axis piezoelectric force sensor measures the forces exerted by the foot. Data from these sensors can be used to run force control algorithms for improving locomotion on soft and irregular terrain.
iai.csic.es/users/silo4/
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iai.csic.es/users/jestremera … WMV50b.WMV

**My self along with a few others on these forums are trying to compile a stable quadruped gait.

This video is especially important to me as my current project is of similar construct, using Radial leg movements rather than Linear!

i am not a programmer but i do know a bit about atom code so any info on Realtime, omnidirectional, gait control would be greatly excepted!

enjoy the vids!**

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I am a programmer, but not a math guru.

I assume this is an old school idea, but for completeness sake.
The state-process of a dynamic quad gait i describe as such:[code]1. See which tripod’s the legs currently make.
1a 4 feet down = 4 tripod area’s
1b 3 feet down = 1 tripod [GOTO 1]

  1. Find out which tripod stance has the lowest usefulness** value, but not 0.

  2. In this tripod, release the leg that can win the most terrain in the direction the body wants to go.[GOTO 1][/code]** usefulness = (distance body COG … tripod edge) * (1 if the body is moving away from most legs in tripod, else 0)

The actual leg motion control could be outsourced to existing code.
Mind that “body COG” actually shifts while legs extend/retract, but that won’t affect us much.
This is an over-simplified depiction, and some stuff should be a configurable multiplier.