Flyer
The system detailed here is a four-motor rotary wing aircraft equipped with 3-inch propellers. The first version measures approximately four inches in overall size. Communication and control are facilitated by a 418MHz digital radio, while an onboard PIC17 microcontroller and L293DD MOSFET power chips drive the motors. The printed circuit boards are arranged in an X shape, serving as the frame that supports the motors, hence the designation "PCB flyer." A second version of the flyer has been developed using Astroflight Firefly motors with 16:1 gearboxes that drive 10-inch custom propellers at 2000 RPM. This version employs Murata rate gyros for stabilization and is powered by a battery pack consisting of four 2/3 size Tadiron lithium cells. The schematics and construction details of the second version are provided. The PCB flyer serves as a systems integration test bed designed to explore various methods of communication, sensing, stabilization, and control. The investigation of algorithms and techniques for flight stability and semi-autonomous navigation necessitates a flexible and programmable prototyping platform, which is essential for validating physical simulations of both flight characteristics and sensor functions. The system comprises two primary components: a custom ground transmitter for radio communications and control, and the flyer itself, which contains an onboard microcontroller, radio, and other peripherals. The motors used are Watt-Age Sub Micro B2 motors fitted with custom propellers, similar to B2 props but available in both left-handed and right-handed configurations. The power source is an eight-cell pack of 50 mAh Sanyo NiCads. The flyer weighs 9 grams without the motors or battery. The custom transmitter utilizes a Great Planes Real Flight Futaba controller with a joystick port output connected to a board housing a Microchip PIC17C756A microcontroller and a Linx Technologies 418MHz RF digital transmitter. This radio transmits serial data at 4800 baud with a range of 300 feet and can be upgraded to support a higher bandwidth two-way digital communications link. The PIC microcontroller samples the joystick port, converting joystick values for roll, pitch, yaw, and throttle into motor controls for the front, left, back, and side motors. It then transmits this data along with button settings to the flyer. The system employs a matrix to express the relationship between the distance from the center of mass to each motor and the linear (approximate) relationship between lift and drag. The matrix is inverted to calculate the power supplied to the front, left, back, and right motors based on the joystick settings for roll, pitch, yaw, and throttle. Pitch control is achieved through differential power distribution to the front and back motors, while roll is managed by varying power to the left and right motors. Yaw control is facilitated by the opposing rotation of the front and back props (counterclockwise as viewed from below) and the left and right props (clockwise). By adjusting the power to the front/back and left/right motor pairs, the flyer can be maneuvered accordingly. The flyer, depicted below, is fundamentally a flying printed circuit board, with a thin, lightweight 20 mil circuit board serving as the frame to which the motors are affixed using cyanoacrylate glue. The battery connector also functions as the battery support post. The PIC17 microcontroller can be easily expanded with additional sensory and communication components, as well as enhanced control software to integrate their functionalities. The surface mount PIC17 processes incoming motor controls from the Linx Technologies 418MHz receiver through a serial digital interface and one of the PIC17's two UARTs. The PIC17 utilizes its three on-chip PWM outputs to manage motor control effectively.
The design of this rotary wing aircraft emphasizes modularity and adaptability, allowing for experimentation with various flight control algorithms and sensory integration. The use of lightweight materials and compact components ensures that the system maintains a low weight, which is critical for flight performance. The integration of a programmable microcontroller facilitates real-time adjustments and improvements to the flight control system, enabling the exploration of advanced navigation techniques and enhancing the overall capability of the aircraft. The combination of the custom transmitter and the onboard microcontroller creates a robust communication link that supports the dynamic requirements of flight operations, making it suitable for research and development in the field of unmanned aerial vehicles.The system described here is a four motor rotary wing aircraft with 3 inch propellers. The overall size of version one is about four inches. A 418MHz digital radio is used for communications and control and an onboard PIC17 microcontroller and L293DD mosfet power chips drive the motors. The printed circuit boards form an X shape that serves as the frame that holds the motors, hence the name "PCB flyer". A second version of the flyer has been built using Astroflight Firefly motors with 16:1 gearboxes that turn 10 inch custom propellors at 2000 rpm. It uses Murata rate gyros for stabilization and is powered by a battery pack of four 2/3 size Tadiron lithium cells.
The schematics and construction details of version two are described. The PCB flyer is a systems integration test bed that was constructed for exploring various approaches to communication, sensing, stabilization, and control. Exploration of algorithms and techniques for flight stability and semi-autonomous navigation requires a flexible and programmable prototyping platform.
Such a platform is needed to validate physical simulations of both the flight characteristics and sensor functions. The system consists of two main parts, a custom transmitter on the ground for radio communications and control, and a flyer with onboard micro-controller, radio, and other peripherals.
The motors are Watt-Age Sub Micro B2 motors with custom propellers similar to the B2 props but fabricated in both left handed and right handed versions. The battery is an eight-cell pack of 50 mAh Sanyo NiCads. Without motors or battery the flyer weighs 9 grams. The custom transmitter shown below uses a Great Planes Real Flight Futaba controller with a joystick port output plugged into a board containing a Microchip PIC17C756A micro-controller and a Linx Technologies 418MHz RF digital transmitter.
This radio transmits serial data at 4800 baud with a 300 ft range, and can easily be upgraded to a higher bandwidth two-way digital communications link. The PIC micro-controller samples the joystick port, converts the joystick values for roll, pitch, yaw, and throttle, to motor controls for front, left, back, and side motors.
It then transmits this data plus button settings to the flyer. where d represents the distance from the center of mass to each motor and k expresses a linear (approximate) relationship between lift and drag. The matrix is inverted in order to solve for the power to the front, left, back, and right motors given the joystick settings for roll, pitch, yaw, and throttle.
The inverted matrix is of the form Thus pitch is controlled by differential power to front and back motors. Decreasing the front motor and increasing the back motor causes forward pitch. Roll is controlled by differential power to the left and right motors. Yaw control takes advantage of the fact that the front and back props are turning CCW (as viewed from below) and the left and right props are turning CW.
So the front and back props apply a CW torque on the flyer body (as viewed from below) and the left and right motors apply a CCW torque. Yaw is can thus be controlled by differential power to front/back and left/right pairs of motors. If the front/back pair is increased and the left right pair is decreased, the flyer will yaw left. The flyer, shown below, is essentially a flying printed circuit board. The thin, light, 20mil circuit board also serves as the frame to which the motors are attached with CA glue.
The connector for the battery is also the battery support post. The PIC17 micro-controller can easily be extended with additional sensory and communication components as well as additional control software to incorporate their functionality. The surface mount PIC17 reads the incoming motor controls from the Linx Technologies 418MHz receiver via a serial digital interface and one of the PIC17`s two UARTs.
The PIC17 uses its 3 on-chip PWM outputs plus a fo 🔗 External reference
The design of this rotary wing aircraft emphasizes modularity and adaptability, allowing for experimentation with various flight control algorithms and sensory integration. The use of lightweight materials and compact components ensures that the system maintains a low weight, which is critical for flight performance. The integration of a programmable microcontroller facilitates real-time adjustments and improvements to the flight control system, enabling the exploration of advanced navigation techniques and enhancing the overall capability of the aircraft. The combination of the custom transmitter and the onboard microcontroller creates a robust communication link that supports the dynamic requirements of flight operations, making it suitable for research and development in the field of unmanned aerial vehicles.The system described here is a four motor rotary wing aircraft with 3 inch propellers. The overall size of version one is about four inches. A 418MHz digital radio is used for communications and control and an onboard PIC17 microcontroller and L293DD mosfet power chips drive the motors. The printed circuit boards form an X shape that serves as the frame that holds the motors, hence the name "PCB flyer". A second version of the flyer has been built using Astroflight Firefly motors with 16:1 gearboxes that turn 10 inch custom propellors at 2000 rpm. It uses Murata rate gyros for stabilization and is powered by a battery pack of four 2/3 size Tadiron lithium cells.
The schematics and construction details of version two are described. The PCB flyer is a systems integration test bed that was constructed for exploring various approaches to communication, sensing, stabilization, and control. Exploration of algorithms and techniques for flight stability and semi-autonomous navigation requires a flexible and programmable prototyping platform.
Such a platform is needed to validate physical simulations of both the flight characteristics and sensor functions. The system consists of two main parts, a custom transmitter on the ground for radio communications and control, and a flyer with onboard micro-controller, radio, and other peripherals.
The motors are Watt-Age Sub Micro B2 motors with custom propellers similar to the B2 props but fabricated in both left handed and right handed versions. The battery is an eight-cell pack of 50 mAh Sanyo NiCads. Without motors or battery the flyer weighs 9 grams. The custom transmitter shown below uses a Great Planes Real Flight Futaba controller with a joystick port output plugged into a board containing a Microchip PIC17C756A micro-controller and a Linx Technologies 418MHz RF digital transmitter.
This radio transmits serial data at 4800 baud with a 300 ft range, and can easily be upgraded to a higher bandwidth two-way digital communications link. The PIC micro-controller samples the joystick port, converts the joystick values for roll, pitch, yaw, and throttle, to motor controls for front, left, back, and side motors.
It then transmits this data plus button settings to the flyer. where d represents the distance from the center of mass to each motor and k expresses a linear (approximate) relationship between lift and drag. The matrix is inverted in order to solve for the power to the front, left, back, and right motors given the joystick settings for roll, pitch, yaw, and throttle.
The inverted matrix is of the form Thus pitch is controlled by differential power to front and back motors. Decreasing the front motor and increasing the back motor causes forward pitch. Roll is controlled by differential power to the left and right motors. Yaw control takes advantage of the fact that the front and back props are turning CCW (as viewed from below) and the left and right props are turning CW.
So the front and back props apply a CW torque on the flyer body (as viewed from below) and the left and right motors apply a CCW torque. Yaw is can thus be controlled by differential power to front/back and left/right pairs of motors. If the front/back pair is increased and the left right pair is decreased, the flyer will yaw left. The flyer, shown below, is essentially a flying printed circuit board. The thin, light, 20mil circuit board also serves as the frame to which the motors are attached with CA glue.
The connector for the battery is also the battery support post. The PIC17 micro-controller can easily be extended with additional sensory and communication components as well as additional control software to incorporate their functionality. The surface mount PIC17 reads the incoming motor controls from the Linx Technologies 418MHz receiver via a serial digital interface and one of the PIC17`s two UARTs.
The PIC17 uses its 3 on-chip PWM outputs plus a fo 🔗 External reference