ME 218A: Ed’s RV Ed-Splorer

Ed's RV Ed-splorer display featuring a model RV and Stanford landmarks

As part of Smart Product Design (ME 218A, Fall 2023), myself and a team of 2 other students designed and built a mechatronic spotlight game. The project was completed from start to finish in 3 weeks, and was presented at the 2023 ME 218A showcase at the conclusion of the quarter.

Hardware Design

Summary: Design a four-bar linkage that sorts colored discs onto the corresponding colored zones (regular or bonus) of the provided playing field.

Scoring: Points are awarded based on the accuracy of placement within zones. Speed is taken into account — devices capable of sorting 18 randomly ordered discs faster than 90 seconds gain extra points.

Constraints: Each team is provided a kit of linkage parts, which must be used. Custom parts may be machined, but these parts cannot be used in the construction of any of the four links. No part of the mechanism is allowed to touch the Sorting Area, only the Setup Area.

Outline illustration of Stanford University landmarks, including the Hoover Tower, Memorial Church, palm trees, sculptures, and a radio telescope.
Diagram of a gas belt system with labeled parts, including window, full part of gas belt, drum, stabilizing dowel rod, and belt attachment.
Model of an RV on a rectangular platform with dimensions labeled in inches.
Assorted black and white flat plastic pieces arranged on a dark background.

Software Design

Flowchart diagram outlining states and transitions in a system, including states like IDLE, READY, MOVING, BRIGHTNESS_LEVEL_CONTROL, ONE_TARGET_REACHED, ALL_TARGETS_REACHED, and GAME_TIMEOUT. Transitions are triggered by events such as ES_INIT, ES_IDLE_TIMEOUT, ES_JOYSTICK_BUTTON, and others, with actions like posting messages to LED Display Module and PWMService.

To ensure our crank slider would not reach a toggle point, the maximum desired transmission angle is 45°. Using SolidWorks, we determined our design had a maximum transmission angle of 33.88°.

Flowchart of an LED control system with nodes labeled IDLE, WELCOME, WAIT4LIGHT, SAD_ED, DISCO_ED, and BRIGHTNESS SETUP MSG. It shows transitions triggered by events like ES_WAVE_HAND and ES_TIMEOUT, interacting with modules such as LED_Display_Module, SpotlightControl, and PWMService.

Two main state machines were used to achieve functionality.

To ensure our crank slider would not reach a toggle point, the maximum desired transmission angle is 45°. Using SolidWorks, we determined our design had a maximum transmission angle of 33.88°.

Circuit Design

Circuit diagram of an electronic project, showing components such as resistors, capacitors, microcontroller, and modules for joystick, buzzer, path LEDs, and LED display. Includes schematic connections and labels for voltage and ground.

To actuate our linkage, we used a DC motor and encoder, controlled using an Arduino Uno and H-bridge. A color sensor was placed inside our disc feeder to determine which disc was being picked up, and an electromagnet transported the disc to its destination.