Securing an RC motor in case of radio loss.
Conventional radio control systems for RC models (airplanes, cars, robots, lawnmowers, etc.) do not always provide a failsafe in case of signal loss. This can lead to dangerous situations, such as the motor remaining active even when the radio turns off or disconnects. This project offers a simple and effective solution based on an ATtiny85 and an optocoupler to monitor the radio status and automatically shut down the motor in case of signal loss. A so-called safety relay will need to be adapted depending
In this project, I leverage the radio receiver's status LED, which flashes or turns off in case of signal loss.
An optocoupler captures this information, and the ATtiny85 analyzes its signal to determine if the radio connection is stable.
An optocoupler captures this information, and the ATtiny85 analyzes its signal to determine if the radio connection is stable.
If the radio is enabled and functional, the safety relay can be enabled after a brief validation.
In case of signal loss, the safety relay is immediately deactivated.
In case of signal loss, the safety relay is immediately deactivated.
Required Equipment
• Microcontroller: ATtiny85 (8 MHz internal)
• Optocoupler: Cosmo1010 or equivalent
• Resistors: 4.7 kΩ (pull-up), 220 Ω (current limiting)
• Relay or transistor: For motor control
• Power supply: 5V (battery, regulator, etc.)
Electronic Schematic See full schematic "Tiny_Secu_RC_Radio_schema.pdf"
We use a Cosmo1010 optocoupler or similar to capture the radio information.
The optocoupler's input LED is connected in place of the radio receiver's.
The optocoupler's output, collector, control radio LED cathode
The signal for pin A2 of the ATtiny
Radio LED LED D4, mirroring the radio receiver's information; I used a blue one.
We use a Cosmo1010 optocoupler or similar to capture the radio information.
The optocoupler's input LED is connected in place of the radio receiver's.
The optocoupler's output, collector, control radio LED cathode
The signal for pin A2 of the ATtiny
Radio LED LED D4, mirroring the radio receiver's information; I used a blue one.
The Attiny85 receives information from the optocoupler on pin 3, which is A2.
Flashing radio LED: no transmitter found, radio fault.
Fixed LED: the receiver is properly connected to the transmitter.
TINY_RC_SECU_RADIO.ino
Depending on the code and its parameters, which can be adjusted to suit your project, a so-called safety relay is controlled via PB1, pin 6 of the ATtiny.
Flashing radio LED: no transmitter found, radio fault.
Fixed LED: the receiver is properly connected to the transmitter.
TINY_RC_SECU_RADIO.ino
Depending on the code and its parameters, which can be adjusted to suit your project, a so-called safety relay is controlled via PB1, pin 6 of the ATtiny.
Discussion (0 commentaire(s))