```html Seastead Scale Model Testing Plan

Seastead Scale Model Testing Plan

1. Froude Scaling for 1/6 Scale Model

        Full Scale Dimensions:
        Living Area: 40 ft × 16 ft
Columns: 4 ft wide × 24 ft long (at 45° angle)
Full Scale Weight: 36,000 lbs

    

1/6 Scale Model Dimensions:

Component	Full Scale	Scale Factor	1/6 Scale Model
Living Area Length	40 ft = 480 inches	÷6	80 inches
Living Area Width	16 ft = 192 inches	÷6	32 inches
Column Width	4 ft = 48 inches	÷6	8 inches
Column Length	24 ft = 288 inches	÷6	48 inches

Weight Scaling:

For Froude scaling, weight scales with the cube of the length scale:

Scale Factor³ = (1/6)³ = 1/216

Model Target Weight: 36,000 lbs ÷ 216 = 166.7 lbs

2. Cable Tension Measurement

Rubber Surgical Tubing:

Surgical tubing typically has a working tension range of 0.5-15 lbs depending on diameter and length. For a 1/6 scale model, this corresponds to a full-scale tension range of:

Model Tension	Scale Factor	Full Scale Equivalent
0.5 lbs	×216 (force scales with cube of length)	108 lbs
15 lbs	×216	3,240 lbs

Note: This range (108-3,240 lbs) seems reasonable for cable tensions on a 36,000 lb seastead, considering the structure will experience dynamic loads from waves.

Waterproof Digital Tension Loggers:

Instead of surgical tubing, consider these Amazon search terms:

"digital fishing scale with data logging" - Many waterproof models available that can measure and record tension
"handheld dynamometer waterproof"
"rope tension meter digital"
"wireless tension load cell"

Recommendation: Look for fishing scales with Bluetooth data logging capabilities. Brands like Rapala, BogaGrip, or generic "digital luggage scales" with tension functions can often be modified for this purpose.

3. Wave Height Scaling for Anguilla Testing

Full Scale Wave Height	Scale Factor	Model Wave Height
3 feet	÷6	6 inches
5 feet	÷6	10 inches
8 feet	÷6	16 inches

Note: In Sandy Hill Bay, Anguilla, you'll likely find smaller waves (1-3 feet) near shore and larger waves further out. Position your model accordingly to test different conditions.

4. Android Apps for Motion Data

For Acceleration/Pitch/Roll Data:

Phyphox - Excellent for recording accelerometer, gyroscope, and magnetometer data. Can export CSV for analysis.
Sensor Kinetics - Comprehensive sensor data recording
AndroSensor - Records all available sensor data
Physics Toolbox Sensor Suite - Good for motion experiments

For Video with Data Overlay:

Phyphox cannot directly overlay data on video. However, you can:

Record video separately with your phone's camera
Record sensor data simultaneously in Phyphox
Use video editing software (like Kinovea, DaVinci Resolve, or even smartphone apps like "Video Overlay") to combine them

Alternative Apps:

Physics Toolbox Video Suite - Specifically designed to overlay sensor data on video
AR Measure Plan - Some versions include data overlay capabilities

5. Acceleration Metrics for Full-Scale Correlation

Plate Sliding Threshold:

For plates on a table, sliding typically begins at 0.2-0.4 g (where g = 9.8 m/s²). This translates to:

Threshold	Model Acceleration	Full Scale Equivalent
Minimum sliding	0.2 g	0.2 g
Definite sliding	0.4 g	0.4 g

Important: For Froude scaling, accelerations are the same in model and full scale (since acceleration = length/time², and time scales with √length).

Other Useful Acceleration Metrics:

Vertical acceleration > 0.5 g: Objects may become airborne
Lateral acceleration > 0.3 g: People may have difficulty standing
Jerk > 2 g/s: Sudden, uncomfortable motions
Pitch angle > 10°: Significant tilting, objects may slide

6. Additional Measurement Suggestions

Consider Adding:

Inclinometer: Digital inclinometer apps can measure pitch/roll angles
Strain Gauges: On structural members to measure stress
Pressure Sensors: At different depths to measure wave pressure profiles
Current Meters: Small flow sensors to measure water movement around the structure
Photogrammetry: Use multiple camera angles to reconstruct 3D motion
Load Cells: In mooring lines for direct tension measurement
Water Temperature: Affects material properties and buoyancy
Wind Speed: Anemometer to correlate with motion data

Experimental Setup Tips:

Use the water-filled glass with rocks - it's an excellent visual indicator
Consider adding motion-capture markers for more accurate tracking
Test in various wave directions relative to the structure
Record sea state conditions (wave period is as important as height)
Use consistent timing references between all recording devices

Remember: Froude scaling preserves Froude number (Fr = v/√(gL)), which is important for wave-structure interactions. Time scales as √(length scale), so events happen faster in the model. When slowing down video, use factor √6 ≈ 2.45× slower playback speed.

```