Florian Muijres - Profile on Academia.edu (original) (raw)

Papers by Florian Muijres

Supplementary material from "A chordwise offset of the wing-pitch axis enhances rotational aerodynamic forces on insect wings: a numerical study

Most flying animals produce aerodynamic forces by flapping their wings back and forth with a comp... more Most flying animals produce aerodynamic forces by flapping their wings back and forth with a complex wingbeat pattern. The fluid dynamics that underlies this motion has been divided into separate aerodynamic mechanisms of which rotational lift, that results from fast wing pitch rotations, is particularly important for flight control and manoeuvrability. This rotational force mechanism has been modelled using Kutta–Joukowski theory, which combines the forward stroke motion of the wing with the fast pitch motion to compute forces. Recent studies, however, suggest that hovering insects can produce rotational forces at stroke reversal, without a forward motion of the wing. We have conducted a broad numerical parametric study over a range of wing morphologies and wing kinematics to show that rotational force production depends on two mechanisms: (i) conventional Kutta–Joukowski-based rotational forces, and (ii) a rotational force mechanism that enables insects with an offset of the pitch-axis relative to the wing's chordwise symmetry axis to generate rotational forces in the absence of forward wing motion. Because flying animals produce control actions frequently near stroke reversal, this pitch-axis-offset dependent aerodynamic mechanism may be particularly important for understanding control and manoeuvrability in natural flyers.

Supplementary material from "Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics

Using high-speed videography, we investigated how fruit flies compensate for unilateral wing dama... more Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage.

Wing kinematics during sideslip maneuvers in damselflies

Flight control model of landing maneuver in bumblebees

Zoology, Nov 21, 2019

Anopheles gambiae sensu lato is the primary malaria vector, endemic to the African continent and ... more Anopheles gambiae sensu lato is the primary malaria vector, endemic to the African continent and has been found to mate in large swarms. To date, the spatial-temporal characterization of mosquito swarms has been restricted to male-focused interactions and relying on visual observations of field events during sunset. We recorded large-cage laboratory simulated swarm events of Anopheles coluzzii with Photonic Fence Monitoring Device (Photonic Sentry, USA) to characterize various spatial-temporal aspects of male, female, and mixed-sex swarms prior and posterior sunset. Results suggests that male and female mosquitoes form swarms in a spatially similar manner with no visible structural and physical variations within the tested groups. The study of temporal dynamics of swarms reveals a unique composition of swarm hotspot formation for up to one hour in total during night, which is contrary to literature. Our results challenge the paradigm that female mosquitoes are acting as reactive ind...

How bumblebees reject sideways wind while landing

To detect and escape from a looming threat, night-flying insects must rely on other senses than v... more To detect and escape from a looming threat, night-flying insects must rely on other senses than vision alone. Nocturnal mosquitoes have been described to escape looming objects in the dark, but how they achieve this is still unknown. Here, we show how night-active female malaria mosquitoes escape from a rapidly looming object that simulates the defensive action of a blood-host. By combining videography-based automatic tracking with numerical simulations of the attacker-induced airflow, we first show that night-flying mosquitoes use airflow-sensing to detect the danger and trigger their escape. Secondly, by combining these data with mechanistic movement modelling, we unravelled how mosquitoes control their escape manoeuvres: they actively steer away from the danger, and passively travel with the bow-wave produced by the attacker. Our results demonstrate that night-flying mosquitoes escaping from a looming object use the object-induced airflow both to detect the danger, and as fluid m...

The Journal of Experimental Biology, Jul 15, 2019

Most fish species use fast starts to escape from predators. Zebrafish larvae perform effective fa... more Most fish species use fast starts to escape from predators. Zebrafish larvae perform effective fast starts immediately after hatching. They use a C-start, where the body curls into a C-shape, and then unfolds to accelerate. These escape responses need to fulfil a number of functional demands, under the constraints of the fluid environment and the larva's body shape. Primarily, the larvae need to generate sufficient escape speed in a wide range of possible directions, in a short-enough time. In this study, we examined how the larvae meet these demands. We filmed fast starts of zebrafish larvae with a unique five-camera setup with high spatiotemporal resolution. From these videos, we reconstructed the 3D swimming motion with an automated method and from these data calculated resultant hydrodynamic forces and, for the first time, 3D torques. We show that zebrafish larvae reorient mostly in the first stage of the start by producing a strong yaw torque, often without using the pectoral fins. This reorientation is expressed as the body angle, a measure that represents the rotation of the complete body, rather than the commonly used head angle. The fish accelerates its centre of mass mostly in stage 2 by generating a considerable force peak while the fish 'unfolds'. The escape direction of the fish correlates strongly with the amount of body curvature in stage 1, while the escape speed correlates strongly with the duration of the start. This may allow the fish to independently control the direction and speed of the escape.

Journal of Experimental Biology

ABSTRACTHabitat specialization can influence the evolution of animal movement in promoting diverg... more ABSTRACTHabitat specialization can influence the evolution of animal movement in promoting divergent locomotor abilities adapted to contrasting environmental conditions, differences in vegetation clutter or predatory communities. While the effect of habitat on the evolution of locomotion and particularly escape performance has been well investigated in terrestrial animals, it remains understudied in flying animals. Here, we investigated whether specialization of Morpho butterfly species into different vertical strata of the Amazonian forest affects the performance of upward escape flight manoeuvres. Using stereoscopic high-speed videography, we compared the climbing flight kinematics of seven Morpho species living either in the forest canopy or in the understory. We show that butterflies from canopy species display strikingly higher climbing speed and steeper ascent angle compared with understory species. Although climbing speed increased with wing speed and angle of attack, the hig...

Quantifying and Analyzing Mosquito Movement from Video Tracking Results

CSH Protocols, Sep 27, 2022

After tracking the kinematics of a moving mosquito from video, one needs to convert the tracking ... more After tracking the kinematics of a moving mosquito from video, one needs to convert the tracking output into the kinematics data needed to answer the research question. Here, we provide general guidelines for how to do this by discussing how to quantify body position and orientation in the world reference frame and wing and leg orientation in the mosquito body reference frame. These guidelines should be adapted based on the goal of your research. To answer your research question, the resulting kinematics data must then be further analyzed. Because the nature of this analysis depends strongly on your specific research question, we refer to literature for designing these postprocessing routines.

Functional Ecology, Sep 21, 2017

1. Long-distance migrants are time-constrained as they need to incorporate many annual cycle stag... more 1. Long-distance migrants are time-constrained as they need to incorporate many annual cycle stages within a year. Migratory passerines moult in the short interval between breeding and migration. To widen this interval, moult may start while still breeding, but this results in flying with moulting wings when food provisioning. 2. We experimentally simulated wing gaps in breeding male pied flycatchers by plucking two primary feathers from both wings. We quantified the nest visitations of both parents, proportion of high-quality food brought to the nestlings and adults and nestlings condition. Differences in oxidative damage caused by a possible reduction in flight efficiency were measured in amounts of ROMs and OXY in the blood. We also measured how flight performance was affected with recordings of the male`s escape flight using high-speed cameras. Finally, we collected data on adult survival, clutch size and laying date in the following year. 3. "Plucked" males travelled a 5% shorter distance per wingbeat, showing that our treatment reduced flight performance. In line with this, "plucked" males visited their nests less often. Females of "plucked" males, however, visited the nest more often than controls, and fully compensated their partner's reduced visitation rate. As a result, there were no differences between treatments in food quality brought to the nest, adult or chick mass or number of successfully fledged chicks. Males did not differ in their oxidative damage or local survival to the following year. In contrast, females paired with plucked males tended to return less often to breed in the next year in comparison to controls, but this difference was not significant. For the birds that did return, there were no effects on breeding. 4. Our results reveal that wing gaps in male pied flycatchers reduce their flight performance, but when it occurs during breeding they prioritise their future reproduction by reducing parental care. As a result, there is no apparent detriment to their condition during breeding. Because non-moulting females are able to compensate their partner's reduced care, there is also no immediate cost to the offspring, but females may pay the cost suffering from a reduced survival.

How to catch a malaria mosquito? Study and development of odour-baited traps

Using Videography to Study the Biomechanics and Behavior of Freely Moving Mosquitoes

CSH Protocols, Sep 27, 2022

Female mosquitoes of most species require a blood meal for egg development. When biting a human h... more Female mosquitoes of most species require a blood meal for egg development. When biting a human host to collect this blood meal, they can spread dangerous diseases such as malaria, yellow fever, or dengue. Researchers use videography to study many aspects of mosquito behavior, including in-flight host-seeking, takeoff, and landing behaviors, as well as probing and blood feeding, and more. Here, we introduce protocols on how to use videography to capture and analyze mosquito movements at high spatial and temporal resolution, in two and three dimensions.

Designing a Generic Videography Experiment for Studying Mosquito Behavior

CSH Protocols, Sep 27, 2022

In this protocol, we describe the basic design considerations and general method to set up a vide... more In this protocol, we describe the basic design considerations and general method to set up a videography system to study mosquito behavior. A basic videography system to study mosquito behavior requires one or more cameras with an optical lens, camera lighting, a calibration setup, and a system to record the video data or otherwise control the camera. Here, we define two types of systems: (1) a real-time videography-based tracking system for determining the position of multiple moving (flying) mosquitoes, and (2) a high-fidelity videography system that can track the detailed movements of body, wings, and legs of a single mosquito at high spatial and temporal resolutions. These high-fidelity trackers are divided into single-camera systems for studying two-dimensional (2D) movements, and multicamera systems that can reconstruct three-dimensional (3D) movements of the mosquito.

Tracking the Body, Wing, and Leg Kinematics of Moving Mosquitoes

CSH Protocols, Sep 28, 2022

In this protocol, we discuss general techniques for tracking the three-dimensional (3D) locations... more In this protocol, we discuss general techniques for tracking the three-dimensional (3D) locations of the mosquito body, wings, legs, or other features of interest using videos. Tracking data must be acquired to produce detailed kinematics of moving mosquitoes. The software of focus for this protocol, DLTdv, was chosen for its widespread use and excellent support and because it is open-source. In addition, DLTdv allows both manual and automatic tracking. The automatic tracking can be done using a classic machine vision or machine-learning algorithm. The software supports both single-camera analysis and multicamera systems and can take advantage of sophisticated calibration algorithms, both for intrinsic lens distortion correction and for 3D DLT-based reconstruction. For this protocol, we assume all kinematic data is acquiredpost hocthrough video analysis.

CSH Protocols, Sep 28, 2022

Tracking mosquitoes in real time, as opposed to recording video files and performing the tracking... more Tracking mosquitoes in real time, as opposed to recording video files and performing the tracking step later, is useful for two reasons. The first is efficiency. Real-time tracking requires less storage because video images do not need to be saved and followed by a tracking step. The second is that tracking data can be used to interact with the animal in some way, such as triggering the approach of a looming object. In this protocol, we discuss the use of Braid, free software for performing real-time, multicamera, multianimal tracking. We describe a setup with four cameras capable of tracking the threedimensional (3D) position of mosquitoes at 100 frames per second in a volume of 30 cm × 30 cm × 60 cm with millimeter accuracy. The specific hardware configuration is flexible and can be substituted using different or additional components to adjust the tracking parameters as needed. MATERIALS It is essential that you consult the appropriate Material Safety Data Sheets and your institution's Environmental Health and Safety Office for proper handling of equipment and hazardous materials used in this protocol.

Wake visualization of a heaving and pitching foil in a soap film

Journal of Fluid Mechanics, Jan 26, 2023

Visualization of Vortex Wake Interactions

The fluid dynamics of insect wings and the fins and tails of fish are governed by vortex wake int... more The fluid dynamics of insect wings and the fins and tails of fish are governed by vortex wake interactions, which are strongly related to the wing, fins and tail kinematics. By modeling the kinematics of these wings, fins and tails as a two-dimensionally flapping foil, the influence of the kinematics on the vortex wake interactions is studied. This is done by varying the non-dimensional advance ratio -which describes the amount of foil chord lengths traveled during one falling cycle- and keeping the other independent variables constant. The vortex wake interactions in the wake of the flapping foil as a function of the advance ratio were studied with so-called soap-film tunnel technique: a planar film of soap runs down between two wires at constant flow velocity. In this soap-film the vorticity field in the wake of the flapping foil can directly be visualized using a high speed camera and monochromatic illumination. Different vortex wake pattern domains were found for various advance ratios. This shows that the vortex wake interactions are strongly related to the advance ratio as well as the behavior of the Leading Edge Vortex (LEV). At low advance (Less)

Bumblebees Land Rapidly by Intermittently Accelerating and Decelerating Towards the Surface During Visually Guided Landings

Social Science Research Network, 2022

Supplementary material from "A chordwise offset of the wing-pitch axis enhances rotational aerodynamic forces on insect wings: a numerical study

Most flying animals produce aerodynamic forces by flapping their wings back and forth with a comp... more Most flying animals produce aerodynamic forces by flapping their wings back and forth with a complex wingbeat pattern. The fluid dynamics that underlies this motion has been divided into separate aerodynamic mechanisms of which rotational lift, that results from fast wing pitch rotations, is particularly important for flight control and manoeuvrability. This rotational force mechanism has been modelled using Kutta–Joukowski theory, which combines the forward stroke motion of the wing with the fast pitch motion to compute forces. Recent studies, however, suggest that hovering insects can produce rotational forces at stroke reversal, without a forward motion of the wing. We have conducted a broad numerical parametric study over a range of wing morphologies and wing kinematics to show that rotational force production depends on two mechanisms: (i) conventional Kutta–Joukowski-based rotational forces, and (ii) a rotational force mechanism that enables insects with an offset of the pitch-axis relative to the wing's chordwise symmetry axis to generate rotational forces in the absence of forward wing motion. Because flying animals produce control actions frequently near stroke reversal, this pitch-axis-offset dependent aerodynamic mechanism may be particularly important for understanding control and manoeuvrability in natural flyers.

Supplementary material from "Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics

Using high-speed videography, we investigated how fruit flies compensate for unilateral wing dama... more Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage.

Wing kinematics during sideslip maneuvers in damselflies

Flight control model of landing maneuver in bumblebees

Zoology, Nov 21, 2019

Anopheles gambiae sensu lato is the primary malaria vector, endemic to the African continent and ... more Anopheles gambiae sensu lato is the primary malaria vector, endemic to the African continent and has been found to mate in large swarms. To date, the spatial-temporal characterization of mosquito swarms has been restricted to male-focused interactions and relying on visual observations of field events during sunset. We recorded large-cage laboratory simulated swarm events of Anopheles coluzzii with Photonic Fence Monitoring Device (Photonic Sentry, USA) to characterize various spatial-temporal aspects of male, female, and mixed-sex swarms prior and posterior sunset. Results suggests that male and female mosquitoes form swarms in a spatially similar manner with no visible structural and physical variations within the tested groups. The study of temporal dynamics of swarms reveals a unique composition of swarm hotspot formation for up to one hour in total during night, which is contrary to literature. Our results challenge the paradigm that female mosquitoes are acting as reactive ind...

How bumblebees reject sideways wind while landing

To detect and escape from a looming threat, night-flying insects must rely on other senses than v... more To detect and escape from a looming threat, night-flying insects must rely on other senses than vision alone. Nocturnal mosquitoes have been described to escape looming objects in the dark, but how they achieve this is still unknown. Here, we show how night-active female malaria mosquitoes escape from a rapidly looming object that simulates the defensive action of a blood-host. By combining videography-based automatic tracking with numerical simulations of the attacker-induced airflow, we first show that night-flying mosquitoes use airflow-sensing to detect the danger and trigger their escape. Secondly, by combining these data with mechanistic movement modelling, we unravelled how mosquitoes control their escape manoeuvres: they actively steer away from the danger, and passively travel with the bow-wave produced by the attacker. Our results demonstrate that night-flying mosquitoes escaping from a looming object use the object-induced airflow both to detect the danger, and as fluid m...

The Journal of Experimental Biology, Jul 15, 2019

Most fish species use fast starts to escape from predators. Zebrafish larvae perform effective fa... more Most fish species use fast starts to escape from predators. Zebrafish larvae perform effective fast starts immediately after hatching. They use a C-start, where the body curls into a C-shape, and then unfolds to accelerate. These escape responses need to fulfil a number of functional demands, under the constraints of the fluid environment and the larva's body shape. Primarily, the larvae need to generate sufficient escape speed in a wide range of possible directions, in a short-enough time. In this study, we examined how the larvae meet these demands. We filmed fast starts of zebrafish larvae with a unique five-camera setup with high spatiotemporal resolution. From these videos, we reconstructed the 3D swimming motion with an automated method and from these data calculated resultant hydrodynamic forces and, for the first time, 3D torques. We show that zebrafish larvae reorient mostly in the first stage of the start by producing a strong yaw torque, often without using the pectoral fins. This reorientation is expressed as the body angle, a measure that represents the rotation of the complete body, rather than the commonly used head angle. The fish accelerates its centre of mass mostly in stage 2 by generating a considerable force peak while the fish 'unfolds'. The escape direction of the fish correlates strongly with the amount of body curvature in stage 1, while the escape speed correlates strongly with the duration of the start. This may allow the fish to independently control the direction and speed of the escape.

Journal of Experimental Biology

ABSTRACTHabitat specialization can influence the evolution of animal movement in promoting diverg... more ABSTRACTHabitat specialization can influence the evolution of animal movement in promoting divergent locomotor abilities adapted to contrasting environmental conditions, differences in vegetation clutter or predatory communities. While the effect of habitat on the evolution of locomotion and particularly escape performance has been well investigated in terrestrial animals, it remains understudied in flying animals. Here, we investigated whether specialization of Morpho butterfly species into different vertical strata of the Amazonian forest affects the performance of upward escape flight manoeuvres. Using stereoscopic high-speed videography, we compared the climbing flight kinematics of seven Morpho species living either in the forest canopy or in the understory. We show that butterflies from canopy species display strikingly higher climbing speed and steeper ascent angle compared with understory species. Although climbing speed increased with wing speed and angle of attack, the hig...

Quantifying and Analyzing Mosquito Movement from Video Tracking Results

CSH Protocols, Sep 27, 2022

After tracking the kinematics of a moving mosquito from video, one needs to convert the tracking ... more After tracking the kinematics of a moving mosquito from video, one needs to convert the tracking output into the kinematics data needed to answer the research question. Here, we provide general guidelines for how to do this by discussing how to quantify body position and orientation in the world reference frame and wing and leg orientation in the mosquito body reference frame. These guidelines should be adapted based on the goal of your research. To answer your research question, the resulting kinematics data must then be further analyzed. Because the nature of this analysis depends strongly on your specific research question, we refer to literature for designing these postprocessing routines.

Functional Ecology, Sep 21, 2017

1. Long-distance migrants are time-constrained as they need to incorporate many annual cycle stag... more 1. Long-distance migrants are time-constrained as they need to incorporate many annual cycle stages within a year. Migratory passerines moult in the short interval between breeding and migration. To widen this interval, moult may start while still breeding, but this results in flying with moulting wings when food provisioning. 2. We experimentally simulated wing gaps in breeding male pied flycatchers by plucking two primary feathers from both wings. We quantified the nest visitations of both parents, proportion of high-quality food brought to the nestlings and adults and nestlings condition. Differences in oxidative damage caused by a possible reduction in flight efficiency were measured in amounts of ROMs and OXY in the blood. We also measured how flight performance was affected with recordings of the male`s escape flight using high-speed cameras. Finally, we collected data on adult survival, clutch size and laying date in the following year. 3. "Plucked" males travelled a 5% shorter distance per wingbeat, showing that our treatment reduced flight performance. In line with this, "plucked" males visited their nests less often. Females of "plucked" males, however, visited the nest more often than controls, and fully compensated their partner's reduced visitation rate. As a result, there were no differences between treatments in food quality brought to the nest, adult or chick mass or number of successfully fledged chicks. Males did not differ in their oxidative damage or local survival to the following year. In contrast, females paired with plucked males tended to return less often to breed in the next year in comparison to controls, but this difference was not significant. For the birds that did return, there were no effects on breeding. 4. Our results reveal that wing gaps in male pied flycatchers reduce their flight performance, but when it occurs during breeding they prioritise their future reproduction by reducing parental care. As a result, there is no apparent detriment to their condition during breeding. Because non-moulting females are able to compensate their partner's reduced care, there is also no immediate cost to the offspring, but females may pay the cost suffering from a reduced survival.

How to catch a malaria mosquito? Study and development of odour-baited traps

Using Videography to Study the Biomechanics and Behavior of Freely Moving Mosquitoes

CSH Protocols, Sep 27, 2022

Female mosquitoes of most species require a blood meal for egg development. When biting a human h... more Female mosquitoes of most species require a blood meal for egg development. When biting a human host to collect this blood meal, they can spread dangerous diseases such as malaria, yellow fever, or dengue. Researchers use videography to study many aspects of mosquito behavior, including in-flight host-seeking, takeoff, and landing behaviors, as well as probing and blood feeding, and more. Here, we introduce protocols on how to use videography to capture and analyze mosquito movements at high spatial and temporal resolution, in two and three dimensions.

Designing a Generic Videography Experiment for Studying Mosquito Behavior

CSH Protocols, Sep 27, 2022

In this protocol, we describe the basic design considerations and general method to set up a vide... more In this protocol, we describe the basic design considerations and general method to set up a videography system to study mosquito behavior. A basic videography system to study mosquito behavior requires one or more cameras with an optical lens, camera lighting, a calibration setup, and a system to record the video data or otherwise control the camera. Here, we define two types of systems: (1) a real-time videography-based tracking system for determining the position of multiple moving (flying) mosquitoes, and (2) a high-fidelity videography system that can track the detailed movements of body, wings, and legs of a single mosquito at high spatial and temporal resolutions. These high-fidelity trackers are divided into single-camera systems for studying two-dimensional (2D) movements, and multicamera systems that can reconstruct three-dimensional (3D) movements of the mosquito.

Tracking the Body, Wing, and Leg Kinematics of Moving Mosquitoes

CSH Protocols, Sep 28, 2022

In this protocol, we discuss general techniques for tracking the three-dimensional (3D) locations... more In this protocol, we discuss general techniques for tracking the three-dimensional (3D) locations of the mosquito body, wings, legs, or other features of interest using videos. Tracking data must be acquired to produce detailed kinematics of moving mosquitoes. The software of focus for this protocol, DLTdv, was chosen for its widespread use and excellent support and because it is open-source. In addition, DLTdv allows both manual and automatic tracking. The automatic tracking can be done using a classic machine vision or machine-learning algorithm. The software supports both single-camera analysis and multicamera systems and can take advantage of sophisticated calibration algorithms, both for intrinsic lens distortion correction and for 3D DLT-based reconstruction. For this protocol, we assume all kinematic data is acquiredpost hocthrough video analysis.

CSH Protocols, Sep 28, 2022

Tracking mosquitoes in real time, as opposed to recording video files and performing the tracking... more Tracking mosquitoes in real time, as opposed to recording video files and performing the tracking step later, is useful for two reasons. The first is efficiency. Real-time tracking requires less storage because video images do not need to be saved and followed by a tracking step. The second is that tracking data can be used to interact with the animal in some way, such as triggering the approach of a looming object. In this protocol, we discuss the use of Braid, free software for performing real-time, multicamera, multianimal tracking. We describe a setup with four cameras capable of tracking the threedimensional (3D) position of mosquitoes at 100 frames per second in a volume of 30 cm × 30 cm × 60 cm with millimeter accuracy. The specific hardware configuration is flexible and can be substituted using different or additional components to adjust the tracking parameters as needed. MATERIALS It is essential that you consult the appropriate Material Safety Data Sheets and your institution's Environmental Health and Safety Office for proper handling of equipment and hazardous materials used in this protocol.

Wake visualization of a heaving and pitching foil in a soap film

Journal of Fluid Mechanics, Jan 26, 2023

Visualization of Vortex Wake Interactions

The fluid dynamics of insect wings and the fins and tails of fish are governed by vortex wake int... more The fluid dynamics of insect wings and the fins and tails of fish are governed by vortex wake interactions, which are strongly related to the wing, fins and tail kinematics. By modeling the kinematics of these wings, fins and tails as a two-dimensionally flapping foil, the influence of the kinematics on the vortex wake interactions is studied. This is done by varying the non-dimensional advance ratio -which describes the amount of foil chord lengths traveled during one falling cycle- and keeping the other independent variables constant. The vortex wake interactions in the wake of the flapping foil as a function of the advance ratio were studied with so-called soap-film tunnel technique: a planar film of soap runs down between two wires at constant flow velocity. In this soap-film the vorticity field in the wake of the flapping foil can directly be visualized using a high speed camera and monochromatic illumination. Different vortex wake pattern domains were found for various advance ratios. This shows that the vortex wake interactions are strongly related to the advance ratio as well as the behavior of the Leading Edge Vortex (LEV). At low advance (Less)

Bumblebees Land Rapidly by Intermittently Accelerating and Decelerating Towards the Surface During Visually Guided Landings

Social Science Research Network, 2022