Stiffness comparison: Spacedrone vs standard 7" frame
This document summarizes a simple stiffness comparison between a conventional 7" quad frame and the 7" Spacedrone frame. The goal was to quantify how the spaceframe design and carbon tubing perform under bending and torsion compared to a typical plate-based frame.
Test frames
| Frame | Complete frame weight | Construction |
|---|---|---|
| Stock | 141 g | Conventional plate-based 7" frame |
| Spacedrone | 65 g | Carbon tubing spaceframe with 3D-printed nodes |
The Spacedrone frame is roughly half the weight of the stock frame while targeting similar or better stiffness in key directions.
Bending stiffness (top load)
A 3 kg weight was applied vertically at the top centre of the frame (above the flight controller area). Displacement was measured at the load point.
Results
| Frame | Displacement | Relative stiffness |
|---|---|---|
| Stock | 0.97 mm | 1× (baseline) |
| Spacedrone | 0.14 mm | ~7× stiffer |
The Spacedrone frame showed about 7× higher bending stiffness under this load, with 0.14 mm deflection vs 0.97 mm for the stock frame.
Test setup (Spacedrone)
Bending test setup: 3 kg weight applied at the top centre.
Loaded (comparison)
Spacedrone under 3 kg load (0.14 mm displacement):
Stock frame under same 3 kg load (0.97 mm displacement):
Torsional stiffness
A 200 g weight was placed 27 cm from the centre of rotation to apply a torsional moment. Displacement was measured at the point of load.
Results
| Frame | Displacement | Relative stiffness |
|---|---|---|
| Stock | 1.04 mm | 1× (baseline) |
| Spacedrone | 0.73 mm | ~1.4× stiffer |
The Spacedrone frame was more than 1.4× stiffer in torsion, with 0.73 mm vs 1.04 mm displacement.
Test setup (Spacedrone)
Torsional test setup: 200 g weight at 27 cm from centre.
Torsional load (200 g @ 27 cm)
Weight used for torsional moment.
Spacedrone under torsional load (0.73 mm displacement).
Summary
| Test | Stock (141 g) | Spacedrone (65 g) | Spacedrone advantage |
|---|---|---|---|
| Bending (3 kg top) | 0.97 mm | 0.14 mm | ~7× stiffer |
| Torsion (200 g @ 27 cm) | 1.04 mm | 0.73 mm | ~1.4× stiffer |
At roughly 54% less frame weight, the 7" Spacedrone achieves:
- ~7× higher bending stiffness (top load).
- ~1.4× higher torsional stiffness.