ackermann_msgs

Summary

ackermann_msgs
Version:

1.0.0
Description:

ROS messages for robots using Ackermann steering.
Maintainers:
  • Jim Rothrock <jim DOT rothrock AT protonmail DOT ch>
  • Jack O’Quin <jack DOT oquin AT gmail DOT com>
Licenses:
  • BSD
Urls:
Authors:
  • Jack O’Quin
BuildDepends:
BuildtoolDepends:
 
BuildExportDepends:
 
ExecDepends:
Exports:
  • <architecture_independent/>

Types

Message types

ackermann_msgs/AckermannDriveStamped
Field:
# Time stamped drive command for robots with Ackermann steering.
$Id$
## Time stamped drive command for robots with Ackermann steering.
#  $Id$

Header          header
AckermannDrive  drive
ackermann_msgs/AckermannDrive
Field:
  • steering_angle (float32) –
  • steering_angle_velocity (float32) –
  • speed (float32) –
  • acceleration (float32) –
  • jerk (float32) –
# Driving command for a car-like vehicle using Ackermann steering.
$Id$

Assumes Ackermann front-wheel steering. The left and right front wheels are generally at different angles. To simplify, the commanded angle corresponds to the yaw of a virtual wheel located at the center of the front axle, like on a tricycle. Positive yaw is to the left. (This is not the angle of the steering wheel inside the passenger compartment.)

Zero steering angle velocity means change the steering angle as quickly as possible. Positive velocity indicates a desired absolute rate of change either left or right. The controller tries not to exceed this limit in either direction, but sometimes it might.

## Driving command for a car-like vehicle using Ackermann steering.
#  $Id$

# Assumes Ackermann front-wheel steering. The left and right front
# wheels are generally at different angles. To simplify, the commanded
# angle corresponds to the yaw of a virtual wheel located at the
# center of the front axle, like on a tricycle.  Positive yaw is to
# the left. (This is *not* the angle of the steering wheel inside the
# passenger compartment.)
#
# Zero steering angle velocity means change the steering angle as
# quickly as possible. Positive velocity indicates a desired absolute
# rate of change either left or right. The controller tries not to
# exceed this limit in either direction, but sometimes it might.
#
float32 steering_angle          # desired virtual angle (radians)
float32 steering_angle_velocity # desired rate of change (radians/s)

# Drive at requested speed, acceleration and jerk (the 1st, 2nd and
# 3rd derivatives of position). All are measured at the vehicle's
# center of rotation, typically the center of the rear axle. The
# controller tries not to exceed these limits in either direction, but
# sometimes it might.
#
# Speed is the desired scalar magnitude of the velocity vector.
# Direction is forward unless the sign is negative, indicating reverse.
#
# Zero acceleration means change speed as quickly as
# possible. Positive acceleration indicates a desired absolute
# magnitude; that includes deceleration.
#
# Zero jerk means change acceleration as quickly as possible. Positive
# jerk indicates a desired absolute rate of acceleration change in
# either direction (increasing or decreasing).
#
float32 speed                   # desired forward speed (m/s)
float32 acceleration            # desired acceleration (m/s^2)
float32 jerk                    # desired jerk (m/s^3)