Botmite Construction Details & photos:

Hacks & Mods


  Electronics - Control, Navigation and Function


                                                   See Photos & Sensors for more electronics.

Botmite Aircraft Power and Control:

     Radio Control of this aircraft constitutes the first method in human interaction and guidance of this vehicle moving through airspace. How far it works ( range ) is a matter of real world testing. Failing radio control ( rc ) or interference simply rolls guidance and control over to internal onboard computer ( IMU ) and its associated firmware ( software ). Sky bot constantly processes information from various gyros, accelerometers, GPS, magnetometers and altimeter/airspeed sensors.   

     The Bot, as in “Robot”: Aboard this scale model airplane you can find a plethora of mechanical and electronic instrumentation.  At its core is a one chip computer which lacks the usual hardware footprint or peripherals, such as, keyboard, monitor, printer.  An operating system and specialized application software or firmware of a desktop or laptop computer is not necessary. Word processing or spreadsheets applications are missing. The Bot chip is about the here and now.  Bot size and weight must be small and light; its reactions and actions can not blue screen and crash. Bot firmware must be nimble and resilient to errors - no matter the source.

     Handling Failures: Components: Beginning with components, testing assumptions, logic, and alternatives a Design-in-depth approach means everything from probability through logic should be tested for a variety of scenarios. The implications of various patterns of failure are then considered in most and least likely formats.
   When a component breaks or gets weird, the IMU chip simply changes what code and device is useful from its utilities and  priorities. Firmware becomes learn-ware.

     Real Time Control: Time may be a matter of convenience or urgency. Botmite’s IMU ( Inertial Management Unit ) requires continuous information.  For smooth flying, some gyro or accelerometer output may have up to 30,000 times per second feeds to the IMU.  The machine vision camera, typical of that much information, typically requires a dedicated and fast processing unit. Simple sensors such as IR or LIDAR sky scanners need much less processing power or time. 

       Telemetry: transmits component and sensor status via onboard radio (satellite portion) to home (base). Digital data contains GPS data, inertial sensors, as in, gyros and accelerometers. Also, battery power usage, what’s left, motor power usage, direction heading (yaw), and detailed history of the flight.

       Camera Application: Taking photos is one of the functions of this model airplane bot.  Moving pictures or videos are hosted on this botmite 1 platform. 

       Sensor Integration:  Some Magnetometers and various sensors operate near 3v but the IMU board typically operates in the 5.0 voltage range. See: Sensor page.





Pitot Tubes in Nose

Air Pressure Sensor about full size

Temperature Sensor

 analog fpv 1W,  9.6 to 12V, 1.2 gHz Transmitter
power output depends upon applied Voltage
Removed aluminum heat sink
Added Black finned Aluminum Radiator

Telemetry - Digital Transceiver
this side: computer
flip side: radio

 [Above] Accelerometer: 3 Axis, Mems Gyro: 3Axis, dual GPS input, programming port, 8 channel I/O, battery power backup, Bus: SPI, I2C. Additional: UART, analog I/O, digital I/O: Parallel port.  Electronic Compass input along with 30 sensor ports. Connections: magnetometer: 3 axis; Sensors: Hall, electrostatic, air pressure, air speed, temperature, Infra Red. Inputs: 8 ch. rc.; telemetry: bidirectional. I/O: SPI and I2C bus.

On Left  ----   3 Axis electronic compass ( Magnetometer ) which plugs into IMU circuit board.

GPS receiver - connects to IMU

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