Getting closer to first trail and next up is the receiver. Design of the PCB is probably easier, with just a lot of connectors to different things. The main MPU is the Teensy 3.5 with a built in SD-card reader and loads of pins.
Before I start designing the PCB for the receiver I just wanted to ask if I had forgotten something.
For non VESC users, I’m planning to add connectors for PPM/PWM, main battery voltage and main battery current sensor.
The list I have come up with is
Main relay
VESC
Bluetooth receiver
GPS
SD card (Built in)
BMS
Water pump
Temperature probes (Dallas)
Moisture
IMU
Pressure pads (FSR)
Man overboard (Reed switch)
For non VESC
PWM/PPM
Main battery current sensor
Main battery voltage
They are for safety, mounted on top of the box. One or more (have to test first) has to be pressed and the board has to be level -ish (IMU) before you can start the motor. Once you are off, the FSR have no effect
Thank you very much for your nice piece of work. My questions:
Q1 - what is the SD card for ?
Q2 - Man overboard (Reed switch): how would it work ? I know it is a programming aspect but I had that in mind: when the reed switch is disconnected (electrically open then), the receiver sends a slow decreasing PPM signal to the ESC from last throttle position to zero in 0.5 - 1 - 1.5 (default) or 2 seconds parametrisable from the IO file read from… the SD card(?).
[man_overboard_timer_0.5_1_1.5def_2sec] 1
The SD-Card is for storing telemetry. Will hopefully also be possible to upload the telemetry to your PC via bluetooth (More coding )
I haven’t really thought of how to use this, even dont´t think I will use this on my build but who knows, doesn’t cost anything. It´s up to anyone to utilize this with a reed switch or something else.
I will probably only rely on the IMU to detect ‘Man over board’
I like your idea though, to not just set the power to zero, but to ‘slowly’ power down. This may help the ESC to last longer.
)