Re: [Playerstage-users] car-like robots in stage

[Fred L. <ff...@ab...>]

On Tuesday 24 February 2009, Patrick Beeson wrote:
> In Player, you can send a PLAYER_POSITION2D_CMD_CAR command through the
> position2d interface to Stage.  The vel.pa  of this command is assumed
> to be a steering angle (in degrees) of an Ackerman steering vehicle, not
> an angular velocity -- not the nicest overloading as this is an angle
> and NOT a velocity.

Yes, I was asking because we have a robot that we drive like that.

>
> By default, Stage won't use this _CAR command, but in Stage, you can
> designate a vehicle to use car steering, which will use this _CAR command.
>
> e.g. in my car.inc file included in my stage worldfile:
>
> # a generic car
> define car position
> (
>    # actual size in meters
>    size [4.8 2.12]
>
>    wheelbase 2.33918
>
>    # the car rotates about the rear axle, behind the center of area
>    # it seems front of the car is neg, thus y-offset should be pos
>    origin [1.3 0.0 0]
>
>    # car-like steering
>    drive "car"
>
> .
> .
> .
>
>
> Note that the wheelbase option was recently a patch I submitted for
> Stage and is in version 2.1.1.  I'm unsure if it is in Stage 3.0.  This
> is the distacne between axles' and is important to get accurate steering.

Exactly what I was looking for.

Thanks.

Fred