Mobile Mapping with GNSS vs. Dynamic Mapping with SLAM: A difference in the technologies

Introduction

In the ever-evolving field of surveying, technology has played a pivotal role in improving accuracy, efficiency, and versatility. Two cutting-edge technologies that have made significant contributions to this industry are Mobile Mapping with GNSS (Global Navigation Satellite System) and Dynamic Mapping with SLAM (Simultaneous Localization and Mapping). Both of these approaches have revolutionized the way we gather geospatial data, but they cater to different needs and offer unique advantages. In this blog, we'll explore the differences between these two technologies and delve into the advantages they offer to the surveying industry.

Mobile Mapping with GNSS

Mobile Mapping with GNSS is a technology that relies on a network of satellites to provide highly accurate location and positioning information. GNSS includes well-known systems like GPS (Global Positioning System), GLONASS (Russian satellite navigation system), Galileo (European system), and BeiDou (Chinese system). When integrated into a mobile mapping system, GNSS technology enables surveyors to precisely determine their location and track their movement in real time.

Advantages of Mobile Mapping with GNSS:

1. Accurate Positioning: GNSS technology is known for its accuracy, making it an ideal choice for applications requiring precise geospatial data, such as land surveying and construction site mapping.
2. Efficiency: Mobile mapping with GNSS enables quick data collection and minimizes the need for manual measurements, reducing surveying time and costs.
3. Versatility: It can be used in a wide range of applications, from topographic mapping and infrastructure inspection to forestry management and environmental monitoring.
4. Real-time Data: Surveyors can access real-time positioning information, allowing for immediate decision-making and adjustments in the field.

Dynamic Mapping with SLAM

Dynamic Mapping with SLAM, on the other hand, relies on sensors and algorithms to create detailed maps and track the position of a device in real time. SLAM technology is particularly beneficial in environments where GNSS signals may be weak or unavailable, such as indoor spaces, urban canyons, or dense forests. It operates by continuously building and updating maps while simultaneously estimating the device's location within those maps.

Advantages of Dynamic Mapping with SLAM:

1. Indoor and GPS-Challenged Environments: SLAM is a game-changer for surveyors working in areas where GNSS signals are unreliable, such as interior spaces, tunnels, or densely vegetated regions.
2. High Precision: SLAM systems can achieve high levels of accuracy in mapping, which is crucial for applications like robot navigation, augmented reality, and autonomous vehicles.
3. Real-time Mapping: SLAM provides dynamic, real-time mapping capabilities, enabling users to visualize and interact with the mapped environment instantaneously.
4. Cost-effective: SLAM technology can reduce the reliance on expensive GNSS equipment, making it a cost-effective solution for surveyors.

Choosing the Right Technology

The choice between Mobile Mapping with GNSS and Dynamic Mapping with SLAM depends on the specific requirements of a surveying project. Surveyors must consider factors such as the environment, accuracy requirements, and budget constraints when deciding which technology to employ. Here are some key considerations for making an informed choice:

1. Environmental Conditions: GNSS-based mobile mapping is excellent for open outdoor environments, while SLAM is more suitable for indoor, urban, or challenging outdoor scenarios.
2. Accuracy Requirements: If high accuracy is essential, GNSS is the preferred choice. For applications where centimetre-level precision is necessary, GNSS is the go-to technology.
3. Real-time Needs: If real-time data updates and decision-making are crucial, SLAM can provide an advantage with its dynamic mapping capabilities.
4. Budget Constraints: Consider the cost of the equipment and infrastructure required for each technology. SLAM systems can be more budget-friendly in some cases.

Conclusion

The surveying industry has been transformed by the adoption of Mobile Mapping with GNSS and Dynamic Mapping with SLAM. While Mobile Mapping with GNSS is ideal for open outdoor spaces and applications requiring high accuracy, Dynamic Mapping with SLAM excels in challenging environments, providing real-time data and cost-effective solutions.

Surveyors should carefully assess their project's requirements and environmental conditions to choose the technology that best suits their needs. Ultimately, the advancement of these technologies offers surveyors a versatile toolkit to gather accurate geospatial data efficiently, no matter the terrain or setting.