Mechanical
Mechanical Design
The main pieces include a housing for our photoresistor board, and a set of hollow support arms to hold the servos and laser while hiding wiring. One servo will be mounted to the open end of the shelf, with the other servo mounted orthogonal to the initial servo to provide rotation along the other axis. This second servo will have a laser attached to it to hit the necessary photoresistor shipping ports. The first servo will be square with the photoresistor plate. The master operator side includes two housings, one for sensors and feedback devices and one for the LCD screen and control potentiometers. Reasonable specs for these are PLA at 0.1" thickness, due to very low strength needs. Project's weight and inertia are negligible, due to small size and low load, making FEA unnecessary. Stiffness of materials was considered and thickness increased due to vibrations from servos affecting laser accuracy. Also included in the images below is the mechanical BoM. We had to pay close attention to tolerances and spacing, as redoing a 3D print would take quite some time.
Standby Operator
L-Arm
This component is a 3D printed L-arm used to hold up our servos and laser. It features a screw hole to secure the flange of the first servo. It has been hollowed out to clean up the wiring and hide wires from sight. It will be attached via a flange at the base to the housing below with screws.
Gimbal Connector
This connector is used in piecing together the two servos used to manipulate our laser. The top section wraps around a servo's rotating axis and the hole behind it is where the screw is added. The bottom cylinder connects to the other servo in a similar manner.
Servo-Laser Connector
This part serves to connect the servo on the left opening to the laser, held within the square section.
Photoresistor Housing
This is the 3D printed housing used to support the random set of 16 photoresistor "ports" used in our project. It has a hollowed-out based for hiding wires and breadboards from sight. It also has screw holes for attachments, and cutouts for easier wiring.
Button Extensions
This cylinder serves as a way to extend our buttons above the top of LED and Button Housing above. The wider bottom end ensures that the extension does not fall out in assembly.
Microcontroller Housing
This housing holds the Mega 2560 as well as excess wiring.
LED and Button Housing
This section houses the LEDs that communicate the objectives to hit, along with the buttons used to communicate these LED coordinates to the standby operator.
LCD and 7-Segment Display Housing
This is the housing that will hold our LCD screen and 7-segment display for use in counting and communicating ports hit
Assembly View of Standby Operator
Seen here is the full assembly of our standby operator side. It contains the above mentioned parts, and is assembled via flanges and screws on the underside of the parts. The base contains the parts most important for the user to see, the 7-segment display, LCD, and LED button sections. The other two sections are the photoresistor-arm section which hits our ports, and the storage section for containing our microcontroller and as many wires as possible. Also seen near the arm are the servos, the gimbal connector and servo-laser connector, used to attach and line up the two servos and the laser above the photoresistor board.
Exploded Assembly View
This view shows how the different parts of the assembly interact, as well as some of the underside details
Master Operator
Sensors Housing:
This housing is meant for holding the sensors and responses. Going from left to right and up to down, it will hold the PIR, ultrasonic, tilt, sound, RGB LED, force, bar LED, motor, and finally MPU sensor. The underside is hollow to hide away wires and controllers, with cutouts for power cables.
LCD and Potentiometer Housing:
This section of the master operator section housing is where the microcontroller is stored, as well as excess wiring, the LCD screen, and potentiometers for control.
Assembly view of the master operator side
Exploded and annotated view of the master operator side
Final Builds:
Standby Operator
Master Operator
Actuator Subsystems
The Laser Positioning System:
In this section we show the Gimbal Connector, Servo-laser connector, and the two servos that are used to position the laser.
