In recent years, the integration of drones into various industries has ushered in a new era of data collection and analysis. Among the myriad applications of drone technology, one that stands out is the creation of high-quality 3D models. Drones armed with cameras and sensors can capture detailed aerial imagery, which, when processed using photogrammetry software like Birdi, can yield precise 3D models.
If you're eager to embark on this journey of 3D modelling using drones, we've compiled a set of best practices to help you get started.
The cornerstone of any successful 3D model is high-quality captured data. To ensure the accuracy and quality of your model, it's essential to start with the right foundation. Utilise high-resolution images, especially when in close proximity to the structure you're modelling. Whenever possible, incorporate accurate measurements through Ground Control Points (GCPs). This meticulous approach ensures the creation of a high-quality model.
Timing is crucial when it comes to capturing high-quality data with drones, particularly for photogrammetry. Natural lighting plays a significant role in data acquisition. Flying in conditions that avoid overexposure, underexposure, or excessive shadows is vital for accurate results. If your area of interest includes vegetation, opt for low-wind conditions to minimise movement in the vegetation, which can affect data quality.
Nadir imagery involves positioning the camera or sensor so that it points directly at the ground, creating images that appear as if taken from directly overhead. The recommended flight altitude for nadir imagery is approximately 150-200 feet (approx 45-60 metres). However, this height may vary based on the desired model quality and the presence of surrounding obstacles.
In addition to nadir imagery, capturing oblique imagery is crucial. Oblique imagery is obtained from various angles and heights by circling the structure of interest. The key is to ensure that the target area remains within the frame throughout the flight. The angle at which you position the camera or sensor depends on the specific application and site. For instance, facades of buildings or structures may require images captured at different angles, such as 30º, 45º, or 70º, depending on the altitude.
Proper overlap in your aerial photo coverage is essential for accurate triangulation during data processing. If you're not using flight planning software, you'll need to manually adjust your flight path to achieve a 60 to 70 percent overlap. This overlap ensures that there are enough common features in adjacent images, improving the accuracy of your 3D model. Avoid capturing images with excessive sky in the background to minimise noise in the final model.
After capturing the necessary imagery, the final step is to process the data and create your 3D model. Upload your imagery to your Birdi platform account - (don't have one yet? Join for free here!) - and select either point cloud or mesh as the output file format. This processing stage is where the magic happens, as Birdi works its algorithms to generate a detailed and accurate 3D representation.
It's important to remember that creating a 3D model with a drone requires planning and attention to detail. Additionally, always ensure compliance with relevant regulations and obtain any necessary permits or licenses before deploying drones for this purpose. With dedication to planning and execution, drone-based 3D modelling can deliver outstanding results across various applications.
At Birdi, we're excited to be a part of the future of 3D modelling and drone technology. By following these best practices, you'll be well on your way to unlocking the full potential of this innovative approach.