Festo Emotionbutterflies – Source; DelFly Credit: Cdewagter – Source
Ornithopter drones/unmanned aerial vehicles (UAVs) are a very niche part of unmanned systems but are still becoming more and more popular as time goes on.
These types of UAVs resemble birds or insects and attempt to replicate their biology in their designs. This field is called biomimicry in robotics.
What are ornithopter drones/UAVs?
Ornithopter drones, also called flapping-wing unmanned aerial vehicles (UAVs), are types of drones that use wings that flap to generate lift and thrust and sometimes to hover. They are inspired by the biology of birds or insects in the case of entomopters.
- How Do Ornithopter UAVs Work?
- What Are The Types Of Ornithopter UAVs?
- What Are Ornithopter UAVs Used For?
- What Parts/Components Make Up Ornithopter UAVs?
- What Are The Advantages And Disadvantages Of Ornithopter UAVs?
- Ornithopter UAV Propulsion Systems
- What Are Some Examples Of Ornithopter UAVs?
How Do Ornithopter UAVs Work?
Ornithopter drones/UAVs are unmanned robotic aircraft that generate lift using their lifting surfaces while being powered by a powerplant on-board the vehicle.
Like all aircraft, ornithopter drones experience all four forces of flight. These forces are lift opposing weight (mass+gravity) and thrust opposing drag.
They work in similar ways to fixed-wing UAVs in the way they generate lift. Both use wings shaped like airfoils that require airflow to generate lift.
Check out our full post that dives further into how fixed-wing UAVs work, the differences between fixed-wing and rotary-wing UAVs, applications, parts/components, advantages/disadvantages, powerplants used in them and real examples:
Related Post: What Are Fixed-Wing Drones/UAVs? Everything You Need To Know
Ornithopter drones/unmanned aerial vehicles (UAVs) use flexible wings that are typically angled at a certain pitch that provides both lift and thrust to propel the vehicle forwards along with a tail for stability and control.
Some ornithopter wings are separated into two separate sections called the arm wing (connected to the fuselage) and the hand wing (connected to the arm wing) which each flap/oscillate at slightly different angles and a different time.
When the wing is in the upwards position above the fuselage, it’s called an upstroke. When the wing is in the downwards position below the fuselage, it’s called a downstroke.
The goal is to reduce the resistance induced by the surface area on the top of the wing during the upstroke in order to bring the wing back up as fast as possible without losing too much altitude and/or speed.
Ornithopter drones most often use batteries that power motors connected to mechanical oscillators enabling the flapping motion of their wings.
Some ornithopters use a tail fin that often acts as a rudder to steer the drone right and left in flight which can serve as the primary method of steering the UAV.
Other ornithopters use their actual main wings to steer, changing the angle of both their wings and fuselage.
Typically the tail assembly of an ornithopter consists of a rudder and/or an elevator, tail fin and/or a tailplane, or a blend of both.
The pitch/angle of the elevator on the empennage can typically be adjusted either by hand or mechanically in flight using a servomotor to the need of the operator.
A higher pitch/angle (nose of the craft is higher or lower) means the drone will fly at slower speeds but will be easier to control whereas a lower pitch means the UAV will fly at higher speeds but will become harder to control in flight.
The operator of one of these drones will typically have to make large sweeping turns in order to reduce the loss of altitude.
Take note that not all ornithopter drones can glide.
Ornithopters are typically hand-launched but can also takeoff and land on their own using legs extending from their fuselages.
Some may say that ornithopter drones work in a way that is more similar to rotary-wing UAVs than fixed-wing UAVs.
This is because rotary-wing drones need to quickly rotate their blades/airfoils around a centre shaft in order to manipulate airflow and thus generate lift.
This is very similar to ornithopter drones as they need to quickly flap their wings in order to maintain steady flight.
Check out our full post on what rotary-wing drones/UAVs are where we dive into how they work, applications, parts/components, advantages/disadvantages, common powerplants and examples:
Related Post: What Are Rotary-Wing UAVs? Unmanned Rotorcraft Explained
They are typically powered by batteries and controlled using motors (more on this below).
In reality, ornithopter drones actually most closely resemble hybrid fixed-wing/VTOL UAVs in the way they operate as they can fly both vertically and horizontally in flight. We have a full article on what hybrid fixed-wing/VTOL UAVs are and how they work here.
What Are The Types Of Ornithopter UAVs?
Here are the two types of ornithopters:
- Conventional ornithopters
Conventional ornithopters are flapping-wing drones/unmanned aerial vehicles (UAVs) that mimic all living animals that can fly by flapping their wings.
Entomopters are types of ornithopters that mimic the biology of an insect incorporating an insect’s wing-flapping aerodynamics and figure.
What Are Ornithopter UAVs Used For?
Here are 4 applications for ornithopter drones/UAVs:
- Military intelligence & survelliance operations
- They can be used to fly on other planets that have a thinner atmosphere
- Clearing birds from airports
- Wildlife monitoring
Check out our full post on ornithopter drone applications where we explain what each use case entails and how flapping-wing UAVs are used in them:
Related Post: 6 Awesome Ornithopter Drone/UAV Applications Explained
What Parts/Components Make Up Ornithopter UAVs?
There are several parts and components used in ornithopter drones/UAVs enabling them to function effectively and efficiently in flight. The following are just of few of the many.
Here are the 10 main parts/components that make up ornithopter drones/UAVs:
- Empennage/tail assembly
- Landing gear/undercarriage
- Mechanical oscillators
- Inertial navigation system (INS)
- Electronic speed controller (ESC)
- Radio transmitters and receivers
The fuselage is the main body of a drone that holds important components and payloads. It’s often made of lightweight and durable materials such as carbon composites and other polymers.
This also includes the body which is often made of foam that covers several parts including the fuselage, tail, and airframe.
All ornithopter drones have a head and tail that are hinged together. Some can use this to rotate their entire fuselages in order to turn in flight with or without a rudder at the tail assembly which in some cases provides the same function.
The wings/airfoils are the primary lifting surfaces that flap to generate lift and thrust enabling ornithopters to fly. They are often made of lightweight fabric.
The empennage/tail assembly is the entire tail section of an ornithopter drone used to help control the UAV in flight. This typically includes a tail fin which often acts as a rudder, a tailplane/horizontal stabiliser which often acts as an elevator.
They are often made of the same lightweight fabrics as the wings.
The landing gear/undercarriage is typically made up of small legs, especially in entomopters which can often enable them to takeoff and land on their own. Otherwise, they don’t have landing gear.
Motors (often servos or servomotors) are propulsion devices used to move and power each moving electrical part of the ornithopter.
A servomotor is typically used as it can be programmed to change both the speed and direction of the stator (the rod that attaches to other components such as mechanical oscillators).
Typically both the wings and tail will have their own motors.
Mechanical oscillators are devices that can transfer electrical energy into physical forces repeatedly and continuously. They are typically connected to the stator of a motor and enable the wings to flap.
They are made up of gear units attached to both motors and typically the leading edge/spar of wing frames and additional rods and mounts in order to provide the flapping motion.
Powerplants are devices that supply the drone and its components with power. This includes batteries, solar cells etc (more on this below).
An inertial navigation system (INS) is an electronic device made up of several sensors such as an inertial measurement unit (IMU), barometers, and sometimes magnometers to measure and report a drone’s force, angular velocity and direction, fuselage orientation, altitude, and sometimes magnetic field.
An electronic speed controller (ESC) is a device used in drones to control and change the speed of each of their electric motors.
Radio transmitters and receivers are components that enable the operator to control the UAV, send and receive data from the UAV using electromagnetic waves.
What Are The Advantages And Disadvantages Of Ornithopter UAVs?
Ornithopter drones are not perfect aircraft. They may have many benefits, but they also have several drawbacks which provide strong reasons to steer towards another type of drone.
We’ve split up the advantages and disadvantages into their own separate sections.
Ornithopter drone/UAV advantages
Here are 5 ornithopter drone/UAV advantages:
- They’re much more efficient than other types of UAVs
- They’re typically very safe
- Some are capable of hovering in place during flight
- They have a simple mechanical complexity
- They can expand the capabilities and applications of drones
Ornithopter drone/UAV disadvantages
Here are 6 ornithopter drone/UAV disadvantages:
- They typically have difficulty landing
- They’re typically quite unstable
- They’re challenging to fly
- They often have very low payload capacities
- They cannot be flown in bad weather
- They often cannot fly as fast as other types of UAVs
Check out our full post where we dive into the advantages and disadvantages of ornithopter drones:
Related Post: 11 Ornithopter Drone/UAV Advantages+Disadvantages Explained
Ornithopter UAV Propulsion Systems
Ornithopter drones are most commonly powered using batteries. However, fuel cells and solar energy are other potential powerplants for these aircraft.
Here are 5 ornithopter drone/UAV powerplants & propulsion devices:
- Solar Cells
- Fuel Cells (FCs)
- Laser power beaming
Take note that laser power beaming has not yet been attempted to be used in ornithopter drones but we believe it could in the future.
Check out our full post where we dive into several powerplants and propulsion devices used in drones. For each power source, we expand on how they work, the types, advantages/disadvantages, and examples of drones using it:
Related Post: How Are Drones Powered? 6 Drone Energy Sources Explained
What Are Some Examples Of Ornithopter UAVs?
Here are 11 examples of ornithopter drones/UAVs:
|DelFly||Micro Air Vehicle Lab of the Delft University of Technology & Wageningen University||Entomopter|
|Cybird P1||Neuros Company||Conventional|
|Insectothopter||Central Intelligence Agency (CIA)||Entomopter|
|Micromechanical Flying Insect (MFI)||University of California, Berkeley||Entomopter|
If you’d like to discover who the best drone companies are in the world for the consumer, commercial and military drone markets and some fun facts about them, we have a full post on this topic below:
Related Post: Top Drone Companies/Manufacturers In The World [History, What They Offer, Popular Drones And More]
These types of drones should not be underestimated as they have some incredible potential in the unmanned systems industry.
We hope we helped you understand the beauty of biomimicry and the potential it holds in changing our lives.