Repository navigation
Hardware
The hardware portion of the BowlsEye system features three PCBs - one main board, or shield, that plugs into the Raspberry Pi, and two smaller boards which connect to the transducers and attach to the motor - a housing for the Raspberry Pi and a stand for the motor sub-system align over the Jack.
The PCB designs for the system were done using the open source schematic capture and PCB design software KiCad, which is developed by Cern. The repository features two PCB designs, however only Proto1 has been fully tested, with the results of these tests resulting in the improved design implemented in Proto2. The design folders also contain a bill of materials, which was made with the use of Kifields.
The layouts of the two PCB versions are shown below.
To avoid any issues when powering the Raspberry Pi and motor driving modules, a separate portable 5V USB power bank is used to power the Pi, and a 11.1V 2000mAh rechargeable LiPo battery powers the external circuitry. This ensures that the power for the Raspberry Pi is completely isolated from any external factors.
CAD files are included in the GIT for construction of a mount for the motor/transducer setup. This is designed to fit exactly over the jack, ensuring that even when the bowl is within touching distance the sensor will be able to perform effective imaging. This is formatted for use with AutoCad Fusion3D software, which is cloud-based and free-to-use. You may create an account and find more information here. The structure of the stand consists of one base platform in which to house the motor and four legs with pegs for connection. Diagrams may be seen below (all units in mm).
Base:
Leg:
Assembled:
To house the Raspberry Pi and its PCB shield, an off the shelf enclosure was used. Holes were drilled into this enclosure to allow for the main power on/off switch, LED indicators and connections to the motor module to be easily accessible.