simium
commented
8 years ago This is the schematics of a prototype for a 12V/5V/3V3 PSU that can provide power for DC motors, the Kinect, the Raspberry Pi...
This is the final layout for v1.0:
I've ordered it and it will be fabricated by an online service called OSHPark, which I've worked with before. This is how the final board will look:
The electronic parts will be bought from Farnell Spain.
The Canyonero is a multi-power system with power hungry components like the 4 DC motors or low power components like the Raspberry Pi or the IMU. Thus we must design an efficient PSU that can handle the energy provided by a 12V/10Ah battery and power the several components of the system safely.
Current power needs are:
The 12V will be provided straight from the battery, since the Motor Shield can handle this voltage safely. The 5V and 3.3V voltages will be provided by two LM2576S ICs, which are 3A step-down voltage regulators. They can source plenty of power for the Pi or the sensors.
The battery voltage will be monitored by down-sizing its value by ~3, so we can use the Arduino ADC (10 bits, up to 5V) to read it and use it. Once we know the real battery charge-discharge profile we will model its usage and will provide feedback for the user using LEDs or an LED bar plus a ROS message.
The battery power should be cut at any given moment for safety reasons. An emergency stop button will be added to the Canyonero so the operator can halt the robot when desired. This button will be Normally-Closed, and will open the circuit once it's pressed.