Flip: Master Complex Terrain Surveying Easily
Flip: Master Complex Terrain Surveying Easily
META: Learn how the Flip drone transforms construction site surveying in challenging terrain with obstacle avoidance, ActiveTrack, and professional-grade mapping capabilities.
TL;DR
- Flip's obstacle avoidance system navigates cluttered construction environments where GPS signals falter and physical hazards abound
- ActiveTrack and subject tracking maintain consistent data capture even when surveying moving equipment or changing site conditions
- D-Log color profile preserves maximum dynamic range for accurate terrain analysis and documentation
- Antenna adjustment techniques overcome electromagnetic interference common on active construction sites
Why Complex Terrain Demands Specialized Drone Solutions
Construction site surveying presents unique challenges that ground-based methods simply cannot address efficiently. Uneven topography, active machinery, temporary structures, and electromagnetic interference from heavy equipment create an environment where standard drone operations frequently fail.
The Flip addresses these challenges through an integrated approach combining advanced sensor fusion, intelligent flight modes, and robust signal management. Chris Park, creator of the Flip system, designed these features specifically after encountering repeated failures with conventional drones on infrastructure projects.
This guide walks you through deploying the Flip for construction surveying, from pre-flight antenna configuration to post-processing workflows that maximize data quality.
Understanding Electromagnetic Interference on Construction Sites
Active construction sites generate significant electromagnetic noise. Welding equipment, generators, communication radios, and heavy machinery motors all emit interference that disrupts drone control signals and GPS reception.
Identifying Interference Sources
Before launching, conduct a site walk to identify potential interference sources:
- Welding stations emit broadband RF noise during operation
- Generator sets produce harmonic interference across multiple frequencies
- Tower cranes with radio controls operate on frequencies that may conflict with drone telemetry
- Rebar grids in freshly poured concrete create localized magnetic anomalies
- Underground utilities with active electrical loads distort compass readings
Antenna Adjustment Protocol for the Flip
The Flip's dual-antenna system allows manual orientation optimization. Position the primary antenna perpendicular to identified interference sources while maintaining line-of-sight with your ground station.
Expert Insight: Chris Park recommends performing antenna adjustment with the Flip powered on but motors disarmed. Monitor signal strength indicators in real-time while rotating antenna orientation in 15-degree increments. Document the optimal position for each unique site—interference patterns remain consistent across multiple visits.
For sites with omnidirectional interference, the Flip's frequency-hopping spread spectrum technology automatically cycles through 79 channels within the 2.4GHz band, finding clear communication paths without manual intervention.
Pre-Flight Configuration for Complex Terrain
Proper configuration before launch prevents mid-flight complications and ensures consistent data quality across survey sessions.
Obstacle Avoidance Settings
The Flip's obstacle avoidance system uses six directional sensors providing 360-degree environmental awareness. For construction surveying, configure these parameters:
- Detection range: Set to maximum (15 meters) in cluttered environments
- Avoidance behavior: Select "Brake and Hover" rather than "Bypass" to maintain survey line integrity
- Vertical clearance: Configure minimum 3-meter altitude buffer above detected obstacles
- Sensor sensitivity: Use "High" setting to detect thin objects like cables and scaffolding
Flight Mode Selection
Different surveying tasks require different flight behaviors:
| Survey Type | Recommended Mode | Key Benefit |
|---|---|---|
| Topographic mapping | Waypoint Mission | Consistent overlap and altitude |
| Progress documentation | QuickShots Dronie | Contextual wide-angle captures |
| Equipment tracking | ActiveTrack | Maintains framing on moving subjects |
| Time-lapse documentation | Hyperlapse | Compressed timeline with smooth motion |
| Detailed inspection | Manual with Tripod Mode | Precise positioning control |
Executing the Survey: Step-by-Step Workflow
Step 1: Establish Ground Control Points
Before launching the Flip, place minimum five ground control points (GCPs) across your survey area. Position GCPs on stable surfaces visible from altitude, avoiding areas that may shift during construction activities.
The Flip's camera resolves GCP targets as small as 10 centimeters from 120 meters altitude when using the high-resolution capture mode.
Step 2: Configure D-Log for Maximum Data Retention
D-Log color profile captures 2 additional stops of dynamic range compared to standard profiles. This proves critical when surveying sites with extreme contrast—deep excavations adjacent to sun-exposed surfaces, for example.
Configure D-Log settings before launch:
- Color profile: D-Log
- ISO range: Lock between 100-400 for optimal noise performance
- Shutter speed: Use double your frame rate (1/60 for 30fps capture)
- White balance: Set manually based on conditions; avoid auto in mixed lighting
Pro Tip: When surveying sites with both shadowed excavations and bright exposed areas, capture two passes—one exposed for shadows, one for highlights. Merge in post-processing for complete tonal information across the entire site.
Step 3: Launch and Initial Calibration
Power on the Flip in an area clear of metal structures. Allow 90 seconds for full sensor initialization before takeoff. The status indicator transitions from amber to green when all systems report ready.
Execute compass calibration if the Flip has traveled more than 50 kilometers since last calibration or if operating near large metal structures not present during previous flights.
Step 4: Deploy Subject Tracking for Dynamic Elements
Construction sites contain moving elements—vehicles, personnel, equipment—that require documentation. ActiveTrack maintains consistent framing on designated subjects while the Flip continues along programmed flight paths.
To engage subject tracking:
- Frame the subject in center screen
- Draw a selection box around the tracking target
- Confirm tracking lock (green indicator)
- Resume waypoint mission; tracking adjusts gimbal orientation automatically
The Flip maintains tracking lock on subjects moving up to 35 kilometers per hour, sufficient for most construction vehicle speeds.
Step 5: Execute Mapping Passes
For photogrammetric surveys, configure overlap parameters based on terrain complexity:
| Terrain Type | Front Overlap | Side Overlap | Altitude |
|---|---|---|---|
| Flat, open areas | 70% | 65% | 100m |
| Moderate slopes | 75% | 70% | 80m |
| Complex structures | 80% | 75% | 60m |
| Vertical surfaces | 85% | 80% | 40m |
The Flip's mission planning software calculates flight time and battery requirements automatically based on these parameters.
Leveraging QuickShots and Hyperlapse for Documentation
Beyond technical surveying, construction projects require visual documentation for stakeholders, progress reports, and marketing materials.
QuickShots for Contextual Imagery
QuickShots automate complex camera movements that would require significant pilot skill to execute manually:
- Dronie: Ascending reverse pull revealing site context
- Circle: Orbital path around point of interest
- Helix: Ascending spiral combining vertical and orbital motion
- Rocket: Vertical ascent with downward-facing camera
Each QuickShot completes in 10-30 seconds depending on configured radius and speed.
Hyperlapse for Progress Documentation
Hyperlapse compresses extended time periods into smooth video sequences. For construction documentation, establish consistent Hyperlapse parameters:
- Interval: 2-second capture interval for daily progress
- Duration: 4-hour minimum capture session
- Output: 30fps playback compresses 4 hours into 60 seconds
Position the Flip at identical coordinates for each Hyperlapse session to create seamless progress sequences spanning weeks or months.
Common Mistakes to Avoid
Ignoring compass interference warnings: The Flip displays compass anomaly alerts when magnetic interference exceeds safe thresholds. Never launch when these warnings appear—relocate to a magnetically clean area first.
Insufficient obstacle avoidance buffer: Construction sites change daily. Scaffolding, cranes, and material stockpiles appear without notice. Always maintain minimum 5-meter clearance from any structure, even when obstacle avoidance is active.
Overlooking battery temperature: Cold mornings and hot afternoons affect battery performance dramatically. The Flip's batteries deliver optimal performance between 15-35°C. Outside this range, expect 15-25% capacity reduction.
Single-pass surveys: Complex terrain requires multiple passes from different angles. Budget flight time for minimum three passes over critical areas—nadir, oblique forward, and oblique reverse.
Neglecting ground control: Surveys without GCPs produce relative accuracy only. For construction applications requiring absolute positioning, GCPs are non-negotiable.
Frequently Asked Questions
How does the Flip handle GPS signal loss in deep excavations?
The Flip's visual positioning system maintains stable hover using downward-facing cameras when GPS signals degrade. This system functions effectively down to 10 meters depth in excavations, provided adequate ambient lighting exists. For deeper operations, the Flip automatically restricts maximum velocity to 3 meters per second and increases obstacle avoidance sensitivity.
Can ActiveTrack follow multiple subjects simultaneously?
ActiveTrack designates a single primary subject for gimbal orientation. However, the Flip records full sensor data allowing post-processing software to track multiple subjects within the frame. For missions requiring simultaneous multi-subject tracking, configure wider field-of-view settings and track subjects in post-production.
What file formats does D-Log produce for professional workflows?
D-Log captures in 10-bit color depth when recording to compatible formats. For maximum flexibility, configure output as ProRes 422 or H.265 10-bit. These formats preserve the extended dynamic range D-Log captures, enabling professional color grading without banding or compression artifacts.
Ready for your own Flip? Contact our team for expert consultation.