01
Sense
CNF / PLA blend changes electrical resistance as the landing gear deforms under load.
CNF / PLA Purdue University · Proof of Concept
AIRFRAME
THAT FEELS
IMPACT.
Additively manufactured CNF/PLA landing gear becomes its own sensor through measuring changes in resistance
SENSOR NODE
nRF52840
BLE telemetry · 10 Hz
MATERIALCNF / PLA
STATUSSENSING
01 / MISSION
Continuous structural awareness
Inspecting every UAV by hand doesn’t scale.
UAVs are moving into delivery, infrastructure inspection, agriculture, mapping, search and rescue, and other high-tempo operations. Traditional nondestructive evaluation can become a bottleneck when fleets are large and sorties are frequent.
This proof of concept explores a different model: embed sensing into the structure itself, so the aircraft can report signs of overload, deformation, and hard landing events as they happen.
PROOF OF CONCEPT / UAV TEST ARTICLE
Instrumented quadcopter with additively manufactured self-sensing landing gear.
02 / SYSTEM
From impact to insight
Five stages. One continuous signal chain.
02
Measure
The INA226 senor captures bus voltage and current so resistance can be computed onboard.
INA22603
Package
Firmware packs resistance, voltage, current, and timestamp into a compact telemetry frame.
16-BYTE PACKET04
Transmit
The nRF52840 streams the packet over Nordic UART Service using Bluetooth Low Energy.
BLE · ~100 ms05
Analyze
A Python ground station decodes telemetry, writes structured CSV logs, and enables post-flight analysis.
PYTHON / MATLABData architecture
Airframe → radio → ground station.
The embedded node performs the sensing and data acquisition on the aircraft. A BLE link carries the telemetry to a host computer, where a Python logger decodes the packet and records it for analysis.
Sampling interval100 ms
PayloadR · V · I · t
TransportBLE UART
03 / TELEMETRY
Interactive simulation
Watch the structure respond.
This dashboard is a simulated visualization of the repository’s telemetry flow—not a live feed from the aircraft. Trigger a hard landing to see how a resistance spike can reveal an impact event.
TIME / LAST 20 SEC
04 / HARDWARE
Embedded stack
Minimal hardware.
Useful signal.
The concept relies on commodity embedded electronics paired with a functional material. The structure provides the signal sensor response; the electronics capture and transport it.
BLE-capable microcontroller running the sensing and telemetry firmware.
Measures bus voltage and current used to derive landing-gear resistance.
3D-printed carbon-nanofiber-reinforced polymer landing gear.
Receives Nordic UART packets, decodes values, and writes timestamped CSV logs.
SCHEMATIC
nRF52840 + INA226 sensing interface
05 / RESULTS
Flight-test signal
A landing leaves a fingerprint.
Repository test data shows a sharp resistance peak around the flight event followed by a decay toward baseline. The project uses this response as a basis for differentiating landing severity and identifying potentially damaging events.
“If the aircraft encounters a harsh landing, the overall resistance of the material increases.”
RESEARCH CONTEXT
Multifunctional Materials in Aerospace Applications to Drone Landing Gear
Presented as part of the Purdue Spring Undergraduate Research Conference 2026.
06 / SOFTWARE
Open implementation
Firmware in the air.
Python on the ground.
src/main.inoEMBEDDED
// Pack structural-health telemetry
typedef struct __attribute__((packed)) {
float r;
float v;
float i;
unsigned long timestamp;
} Packet;
p.r = res;
p.v = bv;
p.i = cu;
p.timestamp = millis();
bleuart.write((uint8_t*)&p, sizeof(p));logging_resistance_data_packet.pyGROUND
# Decode the 16-byte BLE packet
r, v, i, t = struct.unpack("fffI", data)
writer.writerow([
t,
r,
v,
i
])
# Persist each run for analysis
VIEW THE BUILD
OPEN GITHUB ↗