Tips For Structural Assemblage; Tips For Power Provision - ADEEPT AWR Wheeled Robot Manual

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4.2 Tips for Structural Assemblage

●Since many servos are used in the product, the servo installation is critical for the robot. Before installing
the rocker arm to the servo, you need to connect the servo to power and make the servo shaft rotate to the central
position, so the rocker arm installed at the designated degree will be in the central position.
●Generally Raspberry Pi will auto run `webServer.py` when booting, when `webServer.py` will control all the
ports connected to servos to send a signal of rotating to the central position. When assembling the servo, you can
connect it to any servo port anytime. After connecting the servo to the port, the gears will rotate to the central
position; assemble the rocker arm to the servo, disconnect the servo from the port, and insert more servos to
repeat rocker arm assembly (all servos will be in the central position).
● When the servo is connected to power, try moving the rocker arm. If it can't be moved, it indicates the
program for the servo
`[RobotName]/initPosServos.py` (replace `[RobotName]` with the folder name of your robot's program) to make
the servo rotate to the central position.
●When booting (it may take 30-50s), it takes a while for the Raspberry Pi to control PCA9685 to set signal of
all servo ports for central position rotating.

4.3 Tips for Power Provision

●When you install the software, assemble the structure and debug the program, you can use a USB cable to
power the raspberry pi. If the raspberry pi is installed with Motor HAT, you can connect the USB cable to the USB
interface on the Motor HAT. Motor HAT will supply power to the raspberry pi through the GPIO interface.
● The demand of different raspberry pi for electric current is different. For example, the raspberry pi 3B
needs at least 2A of current to start up, and the raspberry pi 4 needs 3A to start up normally. You can check the
specifications on your power adapter before you use the power adapter to power the raspberry pi.
●When Motor HAT is connected to a load (such as connecting to a motor or multiple servos), you need to
use a power supply that supports high current to connect to Vin on Motor HAT. You can use two 18650 batteries
that support high current to power Motor HAT. Our product will provide a dual 18650 battery box with 2pin
interface, you can directly connect it to Motor HAT.
● When you use the USB interface on Motor HAT to supply power, Motor HAT's switch does not control
whether to supply power, Motor HAT's switch can only control the power supply of Vin.
●Do not use the USB interface and Vin on the Motor HAT to supply power at the same time. If you need to
debug the program for a long time and do not want to remove the battery, you can set the switch on the Motor
HAT to OFF. So, when using a USB cable to connect Motor HAT, Motor HAT is powered by USB.
●If your robot restarts automatically after starting up or the robot disconnects and restarts suddenly when it
starts moving after been started up normally, it is most likely because your power supply does not output enough
current. When the robot is starting up, it will automatically run the program to put all the servos in the neutral
position. The voltage drop caused by this process causes the raspberry pi to restart.
●We have tested that when using 7.4V power supply, the peak current of the robot is about 3.75A, so you
need to use a battery that supports 4A output.
works; otherwise there's error for the servo program. Run the line