vectornav-vn200 0.1.0

Cross-platform Python driver for the VectorNav VN-200 GPS/INS sensor

vectornav-vn200

Cross-platform Python driver for the VectorNav VN-200 GPS/INS sensor over USB serial.

Uses the ASCII register protocol with pyserial. No vendor SDK required.

Install

pip install vectornav-vn200

Quick start

from vectornav import VN200

with VN200("/dev/cu.usbserial-XXXX") as vn:  # or "COM3" on Windows
    print(vn.read_yaw())           # degrees
    print(vn.read_accel_x())       # m/s^2
    print(vn.read_gps_latitude())  # degrees (WGS84)
    print(vn.read_temperature())   # Celsius

Find your serial port

from vectornav import VN200
print(VN200.list_serial_ports())

Typical port names:

OS	Port
macOS	/dev/cu.usbserial-XXXXXXXX
Linux	/dev/ttyUSB0
Windows	COM3

API reference

Connection

Method	Description
VN200(port, baudrate=115200, timeout=1.0)	Create a driver instance
connect() / disconnect()	Open/close serial. Also works as a context manager (with)
list_serial_ports()	Static method. Returns list of available serial port names

Device info

Method	Returns	Unit
read_model_number()	str	-
read_serial_number()	int	-
read_hardware_revision()	int	-
read_firmware_version()	str	-

Attitude

Method	Returns	Unit
read_yaw()	float	deg
read_pitch()	float	deg
read_roll()	float	deg
read_yaw_pitch_roll()	dict	deg
read_quaternion()	dict (q0-q3)	unitless

Magnetometer (compensated)

Method	Returns	Unit
read_mag_x()	float	Gauss
read_mag_y()	float	Gauss
read_mag_z()	float	Gauss
read_mag()	dict	Gauss

Accelerometer (compensated, includes gravity)

Method	Returns	Unit
read_accel_x()	float	m/s^2
read_accel_y()	float	m/s^2
read_accel_z()	float	m/s^2
read_accel()	dict	m/s^2

Body acceleration (gravity removed)

Reads ~0 when stationary. Uses the onboard attitude estimate to subtract gravity.

Method	Returns	Unit
read_body_accel_x()	float	m/s^2
read_body_accel_y()	float	m/s^2
read_body_accel_z()	float	m/s^2

Gyroscope (compensated)

Method	Returns	Unit
read_gyro_x()	float	rad/s
read_gyro_y()	float	rad/s
read_gyro_z()	float	rad/s
read_gyro()	dict	rad/s

Temperature & pressure

Method	Returns	Unit
read_temperature()	float	deg C
read_pressure()	float	kPa

GPS (5 Hz, onboard receiver)

Method	Returns	Unit
read_gps()	dict	Full GPS solution (LLA + velocity + accuracy)
read_gps_latitude()	float	deg
read_gps_longitude()	float	deg
read_gps_altitude()	float	m (above WGS84 ellipsoid)
read_gps_fix()	int	0=None, 1=Time, 2=2D, 3=3D
read_gps_num_satellites()	int	-
read_gps_ned_velocity()	dict	m/s (north/east/down)
read_gps_ecef()	dict	Full GPS solution in ECEF frame

INS (fused GPS + IMU, up to 400 Hz)

Method	Returns	Unit
read_ins()	dict	INS solution (LLA + attitude + velocity + uncertainties)
read_ins_latitude()	float	deg
read_ins_longitude()	float	deg
read_ins_altitude()	float	m
read_ins_ned_velocity()	dict	m/s
read_ins_ecef()	dict	INS solution in ECEF frame
read_ins_state_lla()	dict	Full state: attitude + pos + vel + accel + angular rate
read_ins_state_ecef()	dict	Full state in ECEF

Batch reads (fewer serial round-trips)

Method	Fields	Description
read_mag_accel_gyro()	9 floats	All compensated 9-axis data
read_ypr_mag_accel_gyro()	12 floats	Attitude + 9-axis
read_ypr_body_accel_gyro()	9 floats	Attitude + body accel (no gravity) + gyro
read_quat_mag_accel_gyro()	13 floats	Quaternion + 9-axis
read_imu()	11 floats	Uncompensated 9-axis + temperature + pressure
read_delta_theta_velocity()	7 floats	Coning/sculling integrated deltas

Helpers

Method	Description
VN200.parse_ins_status(status)	Decode INS status bitfield into mode, gps_fix, error

Coordinate frames

• Body frame: Right-handed, fixed to sensor. X forward, Y right, Z down (see datasheet Figure 5).
• NED: North-East-Down. Used for GPS/INS velocities.
• ECEF: Earth-Centered Earth-Fixed. Alternative position/velocity frame.
• LLA: Latitude/Longitude/Altitude on WGS84 ellipsoid.

Requirements

• Python >= 3.10
• pyserial >= 3.5
• VN-200 connected via USB (FTDI serial adapter)