GNSS sensors are widely used in the field of self driving cars to determine their position. They help them to navigate from one point to another. Apart from autonomous driving, GNSS sensors can also be used for use-cases like object tracker, weather forecast, security etc. In this blog, I will demonstrate how to use this sensor with Raspberry Pi and get your current location. For this we will require:
But before we directly begin with coding, let us understand how GNSS sensors actually work.
How does a GNSS Sensor work?
Global Navigation Satellite System (GNSS) sensors work by receiving signals from a network of orbiting satellites, such as GPS, GLONASS, or Galileo. These signals contain precise timing and location information, enabling the sensor to calculate its own position on Earth with remarkable accuracy.
GNSS sensors play a pivotal role in the world of modern data collection, especially when coupled with versatile tools like the Raspberry Pi, powered by Python programming. Raspberry Pi’s compact size and low power consumption make it ideal for field deployments, allowing you to gather geospatial data in real-time or over extended periods. Python programming, with its simplicity and rich libraries, facilitates the interface between the Raspberry Pi and GNSS sensor, enabling you to effortlessly log and process location data.
Building the Python code
Now that we know how GNSS works, let’s dive directly into the code and use the sensor to gather our data. We will make use of the serial library of Python. The baudrate with which we communicate with the module is 9600. This is necessary while declaring the serial bus so as to receive data that is comprehensible. Next, we receive different types of NMEA messages, however going into the details of all of them is out of scope of this blog. You can visit this site and read more on the topic. The data format we are interested in is the RMC data. Hence we’ll just log the information from that particular class.
import time
import time, serial
def get_coordinates():
gps = serial.Serial("/dev/ttyACM0", baudrate=9600)
line = gps.readline()
decoded_line = line.decode('utf-8')
data = decoded_line.split(",")
try:
if data[0] == "$GPRMC":
lat_nmea = str(data[3])
dd = float(lat_nmea[:2])
mmm = float(lat_nmea[2:])/60
latitude = dd + mmm
long_nmea = str(data[5])
dd = float(long_nmea[:3])
mmm = float(long_nmea[3:])/60
longitude = dd + mmm
return [longitude, latitude]
else:
return 0,0
except TypeError:
get_coordinates()
while True:
get_coordinates()
It is important to note that the information we receive from this sensor is of NMEA (National Marine Electronics Association) format. To make our coordinates comprehensible, we need to convert them into decimal format. This is done in the code from lines 12 to 20.
Calling the function will ultimately provide your with your latitude and longitude. CONGRATULATIONS! You are now able to extract coordinates using a raspberry pi and can use this for many other applications.
The exciting part is the potential integration of artificial intelligence and machine learning into your GNSS data collection project. By employing AI and ML algorithms, you can extract valuable insights, predict patterns, or automate decision-making processes based on the geospatial data acquired through GNSS sensors. Whether it’s for optimizing routes, tracking assets, or enhancing environmental monitoring, the fusion of GNSS, Raspberry Pi, Python, and AI/ML unlocks a world of possibilities for data-driven solutions that can reshape various industries. Feel free to play around and get creative in integrating machine learning with your GNSS data. Don’t forget to share your amazing ideas in the comments!