AOS T3

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The AOS T3 is the 3" toothpick frame evolved. Best in class resonance performance allows you to enjoy the most responsive ultralight flight experience yet.

The toothpick class has always been about incredible flight performance in a tiny form factor. Relatively large props combined with an ultralight build provides enormous thrust to weight ratio and long flight times. The AOS T3 evolves this class while staying true to Bob Roogi's original toothpick formula.

A key limitation with ultralight frame designs is resonance performance. Placing the motors on the end of very long spindly arms creates a spring-mass system that is prone to resonance in a number of different modes. The AOS T3 uses finite element simulation to model these modes and topology optimization to identify the most efficient places to add material to counteract them, maximize stiffness and increase durability.

The result is a frame that weighs only 10g (13g with the provided 30mm Steel M2 stack screws) with no resonant modes below 200Hz. This allows you to run less filtering and higher D gains to unlock spectacular flight performance and unmatched propwash handling.

Designed for 3" biblade props
1204 or 1303 motors with 9mm mounting
3S 300 - 450mAh battery
25.5x25.5mm and 20x20mm M2 mounting
Canopies available for 14mm Nano and 19mm Micro cameras
Supports Caddx Vista and HDZero Whoop (TX5S.1) VTX

Buy it now! International shipping available

DIY 3D Prints

Recommended Parts

Specification

AOS T3 Canopies

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TOOTHPICK
DESIGN

Ultralight drones feel different

Ultralight drones offer incredibly low propeller disc loading making them extremely agile, direct and resposive in the air. This is point and shoot piloting.

The flight performance and flight feel of toothpick drones stems from their propeller disc loading. Disc loading is the weight of the drone divided by the area swept by its propellers.

When you reduce the weight of a drone as far as possible and use relatively large 2-bladed propellers you can achieve an extremely low disc loading. With a low disc loading the inertia of the drone becomes very small in relation to the thrust of the propellers and the aerodynamic drag created by the propeller disc. The result is a drone that grips the air rather than sliding through it and is incredibly agile and direct in the way it flies.

I think the best analogy is comparing a road car to a Formula 1 or NASCAR racing car. The light weight and high downforce of the racing cars allow them to stick to the road while taking corners at speed rather than sliding. A toothpick drone grips the air in the same way and it's able to change direction instantly like a housefly.

THE CHALLENGE

The Achilles' heel of the Toothpick? Not any more.

Challenge

Vibrations limit flight performance

One of the key limitations with toothpick frames is their tendancy to resonate. Toothpick frames use very thin carbon fibre arms combined with relatively large motors for their weight to swing larger 3" props.

Even the cleanest motors and props produce large amounts of vibration in flight. These vibrations excite the resonant modes of the frame amplifying vibrations at certain frequencies, increasing their amplitude and energy. These vibrations pass into the gyro and create noise on the signal. This noise requires additional filtering and limits maximum PID gains through motor heating.

The result is a flight controller that is slower to respond to propwash and your stick inputs. The AOS T3 is engineered to solve this key problem to improve flight performance. And flight performance has always been one of the goals and benefits of the toothpick class.

Design

THE DESIGN

Understand the design methodology behind the AOS T3

Harmonic analysis is the key

I used Blackbox logging and harmonic analysis to visualize the vibrations of the AOS T3 during the design process. This allowed me to tune the geometry of every part of the frame, moving the frame resonances up and separating them as far as possible. New in the T3 design process is the use of topology optimization to identify the most effective places to add material to improve the stiffness of the frame.

As a result, you can run less filtering. Every layer of filtering adds delay that’s mathematically related to how effectively it removes vibrations. This delay prevents the flight controller from responding rapidly enough to propwash leading to poor propwash handling. Reducing the amount of filtering is the best way to improve propwash handling and flight performance. With the AOS T3 you’ll be in the best possible position to reduce your filtering to an absolute minimum.

Another advantage of lower noise is the ability to run higher PID gains. Higher PID gains allow the quad to track your stick movements with less delay and more precision. The result is greater confidence, particularly when flying tight lines where fast reactions are vital.

KEY FEATURES

See the key features of the frame

Key Features

Top and bottom plates

Both of these plates are 1.5mm thick to provide an optimal balance between strength, stiffness and weight. The cut outs in the bottom plate fits up to a 15mm wide battery strap to securely attach the battery.

There are mountings for a 25.5x25.5mm stack with the long screws in the corner positions or a 20x20mm stack if the long screws are placed in the middle of each side.

Pressnuts keep the screws secure and prevent any flex in the stack even in heavy crashes.

Arms

The AOS T3 uses a truss design with a stabilising strut supporting the middle of the arm. This truss design provides enormous torsional stiffness, resolving a key source of vibration in traditional toothpick frames.

Truss structures are inherently very strong as they convert bending loads into compression and tension in the individual members. Carbon is much stronger in pure tension and compression than in bending.

The frame features motor protector features on the end of each arm to minimize the risk of damage to those expensive components. Should you ever need to replace an arm, there are only two screws to undo making arm replacement easy.