The GPS/GNSS Simulation tool is an interactive virtual platform designed to train land surveyors in GNSS-based positioning concepts and techniques. This advanced tool bridges the gap between theoretical knowledge and field application, providing a controlled environment for experimentation and learning.

1. User Interface and Layout

3D Viewport

• A dynamic Three.js-rendered 3D environment simulates real-world GNSS surveying setups, including:
  • A GNSS receiver model for visualization.
  • A ground plane to simulate the surveying surface.

Control Panel

• GPS/GNSS Settings:

  • Configure parameters such as visible satellites, DOP values (PDOP, HDOP, VDOP), elevation mask, and multipath levels.
  • Helps users understand the effects of each parameter on GNSS performance.

• RTK Base Station Configuration:

  • Adjust RTK base station distance, data link quality, and network type (e.g., VRS, MAC, FKP, Single Base).
  • Simulates RTK precision improvements and challenges.

• Atmospheric Conditions:

  • Customize ionospheric activity and weather conditions to observe their impact on GNSS accuracy.
  • Reinforces how environmental factors influence satellite signal quality.

• Survey Configuration:

  • Choose point collection methods such as single point, continuous topo, or time intervals.
  • Configure offset methods for advanced point capturing.

Satellite Sky Plot

• Real-time visualization of satellite positions in the sky.
• Color-Coded Constellation Legend:
  • Displays satellite constellations like GPS, GLONASS, Galileo, and BeiDou.
  • Trainees can track and differentiate between constellations for better satellite selection.

Status Panel

• Displays critical GNSS quality metrics:
  • Solution type (e.g., RTK Fixed, Float).
  • Horizontal and vertical precision.
  • Latency and overall accuracy.

Mini Map

• Provides a geospatial context for survey locations.
• Simulates the real-time movement of the receiver across the terrain.

Toast Notifications

• Contextual messages guide trainees through survey tasks and provide real-time feedback.

2. Core Functionalities

1. GPS/GNSS Parameter Configuration

• Satellites:

  • Adjust the number of visible satellites to simulate varying signal availability.
  • Test performance with minimal satellite coverage versus optimal conditions.

• DOP Values:

  • Modify PDOP, HDOP, and VDOP values to understand how satellite geometry impacts accuracy.

• Multipath Simulation:

  • Simulate signal reflections off surfaces, a common real-world error source.

• Elevation Mask:

  • Set minimum satellite elevation to avoid low-angle satellites prone to signal distortion.

2. RTK Base Station Setup

• Configure:
  • Base station distance and coordinates.
  • Data link quality to simulate real-world communication challenges.
  • Network RTK types, helping trainees understand the benefits and limitations of each mode.

3. Atmospheric and Environmental Factors

• Adjust ionospheric activity and weather conditions:
  • Observe their effects on signal propagation and accuracy.
  • Train in handling GNSS errors due to environmental disruptions.

4. Survey Point Collection

• Multiple methods for point collection:

  • Single point for high precision.
  • Continuous topo for mapping terrain.
  • Auto by precision for automated point collection based on accuracy thresholds.

• Offset methods for advanced workflows:

  • Simulate measurements in cases of inaccessible survey points.

3. Advanced Features

Satellite Sky Plot Animation

• Satellites dynamically move in the sky plot, visualizing real-time orbits.
• Helps trainees understand satellite availability, visibility, and geometry's role in GNSS accuracy.

Data Export

• Allows export of collected survey data for post-processing or integration with other software.
• Formats include raw data logs and precision reports.

Survey Status Updates

• Real-time updates on survey progress, including the number of collected points and precision levels.

Visualization and Interaction

• 3D visualization of the GNSS receiver, survey area, and satellite signals enhances spatial understanding.
• Simulated animations show the receiver’s rotation and movement, adding realism.

4. Practical Applications for a Land Surveyor in Training

1. Understanding GNSS Fundamentals

• Visualize the role of satellites and constellations in positioning.
• Learn how DOP values and elevation masks influence accuracy.

2. Real-World Error Simulation

• Experiment with multipath effects and ionospheric disturbances.
• Adjust atmospheric settings to replicate adverse conditions.

3. RTK Precision Practice

• Set up and configure RTK networks to experience precision gains in real-time.
• Learn how to interpret solution types (e.g., RTK Fixed vs. Float).

4. Data Collection Techniques

• Practice collecting survey points under different conditions and configurations.
• Understand how point collection methods impact survey workflows.

5. Learning Benefits

Hands-On Training

• Provides a safe, controlled environment to explore GNSS technologies without real-world risks.

Error Management Skills

• Enables trainees to identify, analyze, and mitigate GNSS errors.

RTK and GNSS Workflow Proficiency

• Offers comprehensive training on RTK setup, GNSS parameter optimization, and data collection.

Spatial Awareness

• Sky plot and mini-map integration improve understanding of satellite geometry and its effect on positioning.

6. Benefits of the Tool

• Realism: Combines 3D visuals and real-time simulations to mimic field scenarios.
• Customization: Offers adjustable parameters for tailored learning experiences.
• Feedback: Provides actionable insights through status panels and toast notifications.
• Accessibility: Allows learners to experiment with advanced GNSS concepts without specialized equipment.

Conclusion

The GPS/GNSS Simulation tool is a state-of-the-art training platform for land surveyors, offering a comprehensive introduction to GNSS technologies and techniques. With its blend of realistic simulations, advanced configurations, and interactive learning features, this tool equips trainees with the knowledge and skills to excel in GNSS-based surveying.