Odom

Generic odometry class

The relevant outputs are position (an x/y point) and orientation_deg. Requires an inertial sensor for heading. The math uses the Pilons arc method.

note

Chassis uses an odom instance internally and starts it once set_coordinates is called. You usually only need this class directly when building a custom tracking setup.

Methods

set_physical_distances

void set_physical_distances(float forward_tracker_center_distance,
                            float sideways_tracker_center_distance);

Sets the tracker center distances. The forward tracker center distance is the horizontal distance from the center of the robot to the wheel the sensor measures. The sideways tracker center distance is the vertical distance from the center of the robot to the sideways wheel being measured. If there is no sideways wheel, set its center distance to 0, which is equivalent to a no-drift robot.

Parameter	Description
forward_tracker_center_distance	Horizontal distance to the wheel center, in inches.
sideways_tracker_center_distance	Vertical distance to the wheel center, in inches.

set_position

void set_position(point position, float orientation_deg,
                  float forward_tracker_position, float sideways_tracker_position);

Resets the position, including the tracking wheels. Position is field-centric, and 0 degrees points in the positive Y direction.

Parameter	Description
position	Field-centric x/y position of the robot.
orientation_deg	Field-centered, clockwise-positive orientation.
forward_tracker_position	Current forward sensor position, in inches.
sideways_tracker_position	Current sideways sensor position, in inches.

update_position

void update_position(float forward_tracker_position,
                     float sideways_tracker_position, float orientation_deg);

Runs one odometry update. Compares the input sensor readings against the stored values to update position and orientation_deg.

Parameter	Description
forward_tracker_position	Current forward sensor position, in inches.
sideways_tracker_position	Current sideways sensor position, in inches.
orientation_deg	Field-centered, clockwise-positive orientation.

Public members

Member	Description
position	Current field-centric x/y position.
orientation_deg	Current orientation in degrees.
forward_tracker_center_distance	Configured forward tracker center distance.
sideways_tracker_center_distance	Configured sideways tracker center distance.