Pytrack API

This chapter describes the various libraries which are designed for the Pytrack board. This includes details about the various methods and classes available for each of the Pytrack’s sensors.

3-Axis Accelerometer (LIS2HH12)

Pytrack has a 3-Axis Accelerometer that provides outputs for acceleration as well as roll, pitch and yaw.

Constructors

class LIS2HH12(pytrack = None, sda = 'P22', scl = 'P21')

Creates a LIS2HH12 object, that will return values for acceleration, roll, pitch and yaw. Constructor must be passed a Pytrack or I2C object to successfully construct.

Methods

LIS2HH12.acceleration()

Read the acceleration from the LIS2HH12. Returns a tuple with the 3 values of acceleration (G).

LIS2HH12.roll()

Read the current roll from the LIS2HH12. Returns a float in degrees in the range -180 to 180.

LIS2HH12.pitch()

Read the current pitch from the LIS2HH12. Returns a float in degrees in the range -90 to 90. Once the board tilts beyond this range the values will repeat. This is due to a lack of yaw measurement, making it not possible to know the exact orientation of the board.

GPS with GLONASS (Quectel L76-L GNSS)

Pytrack has a GPS (with GLONASS) that provides outputs longitude/latitude, speed and other information about the Pytrack's location.

Constructors

class L76GNSS(pytrack = None, sda = 'P22', scl = 'P21', timeout = None)

Creates a L76GNSS object, that will return values for longitude and latitude. Constructor must be passed a Pytrack or I2C object to successfully construct. Set the timeout to a time period (in seconds) for the GPS to search for a lock. If a lock is not found by the time the timeout has expired, the coordinates method will return (None, None).

Methods

L76GNSS.coordinates(debug = False)

Read the longitude and latitude from the L76GNSS. Returns a tuple with the longitude and latitude. With debug set to True the output from the GPS is verbose.