Towards Sensor Autonomy in Sub-Gram Flying Insect Robots: A Lightweight and Power-Efficient Avionics System

Talwekar, Yash; Adie, Andrew; Iyer, Vikram; Fuller, Sharon

doi:10.1109/icra46639.2022.9811918

Cited by 5 publications

(5 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be shown using the observability criterion (43) that GRO can observe a state given by q = [θ, ω, v x , z, v z ] ⊤ (see Fig. 2) (44). The key downsides of GRO are excessive weight and power consumption.…”

Section: Resultsmentioning

confidence: 99%

“…13. Two alternatives are an extended Kalman filter at the cost of an additional ≈200 μW (44) or to use a "gain-scheduled" Kalman filter at negligible additional power.…”

Section: Discussionmentioning

confidence: 99%

“…Power usage of the AO camera, the optic flow camera, and rangefinder was measured in the citations provided. We have neglected the mass of a flex circuit and additional required discrete components, which tends to add an additional 25% (44). Even when compared with a version of the drone's GRO suite with the most recent (lighter) version of each sensor, AO is substantially lighter and more power efficient.…”

Section: Power and Massmentioning

confidence: 99%

See 2 more Smart Citations

A gyroscope-free visual-inertial flight control and wind sensing system for 10-mg robots

Fuller

Talwekar

2022

Sci. Robot.

Self Cite

View full text Add to dashboard Cite

Tiny “gnat robots,” weighing just a few milligrams, were first conjectured in the 1980s. How to stabilize one if it were to hover like a small insect has not been answered. Challenges include the requirement that sensors be both low mass and high bandwidth and that silicon-micromachined rate gyroscopes are too heavy. The smallest robot to perform controlled hovering uses a sensor suite weighing hundreds of milligrams. Here, we demonstrate that an accelerometer represents perhaps the most direct way to stabilize flight while satisfying the extreme size, speed, weight, and power constraints of a flying robot even as it scales down to just a few milligrams. As aircraft scale reduces, scaling physics dictates that the ratio of aerodynamic drag to mass increases. This results in reduced noise in an accelerometer’s airspeed measurement. We show through simulation and experiment on a 30-gram robot that a 2-milligram off-the-shelf accelerometer is able in principle to stabilize a 10-milligram robot despite high noise in the sensor itself. Inspired by wind-vision sensory fusion in the flight controller of the fruit fly Drosophila melanogaster , we then added a tiny camera and efficient, fly-inspired autocorrelation-based visual processing to allow the robot to estimate and reject wind as well as control its attitude and flight velocity using a Kalman filter. Our biology-inspired approach, validated on a small flying helicopter, has a wind gust response comparable to the fruit fly and is small and efficient enough for a 10-milligram flying vehicle (weighing less than a grain of rice).

show abstract

Section: Resultsmentioning

confidence: 99%

“…13. Two alternatives are an extended Kalman filter at the cost of an additional ≈200 μW (44) or to use a "gain-scheduled" Kalman filter at negligible additional power.…”

Section: Discussionmentioning

confidence: 99%

Section: Power and Massmentioning

confidence: 99%

See 1 more Smart Citation

A gyroscope-free visual-inertial flight control and wind sensing system for 10-mg robots

Fuller

Talwekar

2022

Sci. Robot.

Self Cite

View full text Add to dashboard Cite

show abstract

“…For simplicity, the model we used in this work excludes damping and drag components, thus setting the force and moment vectors [ f a 1 , f a 2 , f a 3 ] T and [L, M, N] T to zero in equations (2)(3)(4)(5)(6)(7).…”

Section: Model Validationmentioning

confidence: 99%

Modeling and LQR Control of Insect Sized Flapping Wing Robot

Dhingra,

Kaheman,

Fuller

2024

Preprint

View full text Add to dashboard Cite

Flying insects can perform rapid, sophisticated maneuvers like backflips, sharp banked turns, and in-flight collision recovery. To emulate these in aerial robots weighing less than a gram, known as flying insect robots (FIRs), a fast and responsive control system is essential. To date, these have largely been, at their core, elaborations of proportional-integral-derivative (PID)-type feedback control. Without exception, their gains have been painstakingly tuned by hand. Aggressive maneuvers have further required task-specific tuning. Optimal control has the potential to mitigate these issues, but has to date only been demonstrated using approxiate models and receding horizon controllers (RHC) that are too computationally demanding to be carried out onboard the robot. Here we used a more accurate stroke-averaged model of forces and torques to implement the first demonstration of optimal control on an FIR that is computationally efficient enough to be performed by a microprocessor carried onboard. We took force and torque measurements from a 150 mg FIR, the UW Robofly, using a custom-built sensitive force-torque sensor, and validated them using motion capture data in free flight. We demonstrated stable hovering (RMS error of about 4 cm) and trajectory tracking maneuvers at translational velocities up to 25 cm/s using an optimal linear quadratic regulator (LQR). These results were enabled by a more accurate model and lay the foundation for future work that uses our improved model and optimal controller in conjunction with recent advances in low-power receding horizon control to perform accurate aggressive maneuvers without iterative, task-specific tuning.

show abstract

“…Accordingly, academic research on MAV platforms ranging from fixed-wing gliders to bio-inspired flappers has grown steadily since the early 2000s [3]. The science of autonomy at small scales has also advanced: sub-gram electronics payloads are now sufficient for flight control [4], untethered flight of insect-scale robots has been shown with beamed power [5], and groups of MAVs have been shown working together in unstructured environments [6].…”

Section: Introductionmentioning

confidence: 99%

High Aspect Ratio Multi-Stage Ducted Electroaerodynamic Thrusters for Micro Air Vehicle Propulsion

Nelson,

Drew

2024

IEEE Robot. Autom. Lett.

View full text Add to dashboard Cite

Electroaerodynamic propulsion, where force is produced through collisions between electrostatically accelerated ions and neutral air molecules, is an attractive alternative to propeller-and flapping wing-based methods for micro air vehicle (MAV) flight due to its silent and solid-state nature. One major barrier to adoption is its limited thrust efficiency at useful disk loading levels. Ducted actuators comprising multiple seriallyintegrated acceleration stages are a potential solution, allowing individual stages to operate at higher efficiency while maintaining a useful total thrust, and potentially improving efficiency through various aerodynamic and fluid dynamic mechanisms. Here, we investigate the effects of duct and emitter electrode geometries on actuator performance, then show how a combination of increasing cross-sectional aspect ratio and serial integration of multiple stages can be used to produce overall thrusts comparable to state-of-the-art flapping wing robots. A five-stage device is shown to reach a thrust density of about 18 N/m 2 , an order of magnitude higher than what has previously been achieved at this scale, with the same measured thrust efficiency as reported in prior work. We also show how a high aspect ratio multi-stage ducted thruster could be integrated under the wings of a MAVscale platform, pointing towards use as a distributed propulsion system in future work.

show abstract

Towards Sensor Autonomy in Sub-Gram Flying Insect Robots: A Lightweight and Power-Efficient Avionics System

Cited by 5 publications

References 32 publications

A gyroscope-free visual-inertial flight control and wind sensing system for 10-mg robots

A gyroscope-free visual-inertial flight control and wind sensing system for 10-mg robots

Modeling and LQR Control of Insect Sized Flapping Wing Robot

High Aspect Ratio Multi-Stage Ducted Electroaerodynamic Thrusters for Micro Air Vehicle Propulsion

Contact Info

Product

Resources

About