 Description of the structure of the 2N-legged models used in simulation

Below are the description of the 2N-legged model object format and general considerations about the object:

• the format of the object is as following (IRIT syntax):

objModel = list (objBody,
objLegs,
coefStepRotate,
coefStepWalk,
minStepAngle,
stepType)

where

objBody        = <the geometry of the body>
objLegs        = list (
objLegLeft1, objLegLeft2, ..., objLegLeftN,
objLegRight1, objLegRight2, ..., objLegRightN
)
coefStepRotate = numeric value from 0 to 1 that defines "rotation" step length
coefStepWalk   = numeric value from 0 to 1 that defines "walking" step length
minStepAngle   = numeric value that defines the angle of model "rotation" step
(see Mathematical description of trajectory calculation)
stepType       = string value that defines step type ("cross" or "parallel")
where objLegXXX = list (objHip,objShin,coorLeg,coorKnee,coorFoot) where objHip = <geometry of the hip part of the leg> objShin = <geometry of the shin part of the leg> coorLeg = <point with coordinates of the leg origin> coorKnee = <point with coordinates of the knee, i.e. joint between hip and shin> coorFoot = <point with coordinates of the foot> The names aren't important to the parser, just the structure should be preserved.

• Center of the object body should be at (0,0,Z). Z coordinate defines the altitude of the body above the surface (i.e. if the center of the body is at the point (0,0,1) then the simulator will move the body preserving the altitude equal to 1 above the surface.

• The top side of the object should be in direction of vector (0,0,1)

• The head of the object should be in direction of vector (1,0,0)