The Leaky Tree. Alex Bratschun. Jeff Gier. Cassie Hellem. Ryan Stephens

Transcription

1 The Leaky Tree Alex Bratschun Jeff Gier Cassie Hellem Ryan Stephens Table of Contents Design Summary 3 System Details 4 Design Evaluation...9 Lessons Learned 10 Appendix 12

2 Design Summary The Leaky Tree is a top shelf device designed to dispense ice and one of four mixed drinks that can be selected by the user. The purpose of this device is to replace the time-consuming action of pouring complex drinks yourself. This device will conveniently pour an equivalent cold mixed drink for you with just a push of a button. When the device is powered, LEDs in the upper portion, ice container and coaster light up in many colors and patterns to convey information and create a fun light show for the user. The multicolor LCD screen on the electronics panel turns on and automatically scrolls to the first drink selection. The green buttons on either side of the screen allow the user to scroll through four different drink options. Below the drink name is a list of the included flavors. At any time, the blue ice button can be held down and ice will dispense continuously for as long as the button is held. To select the drink, the user presses the white dispense button. Then the ultrasonic sensor will check for a cup on the coaster. While dispensing, the slide and coaster will turn green. FDA-approved solenoid valves are activated via transistors in a predetermined sequence and timing. These solenoids are normally closed and when activated

3 dispense liquid at a predictable rate. When finished dispensing, the screen will display a finished message and the coaster performs a fast alternating pattern. To return to the start screen, the user can remove the cup and place another one on the coaster or press the ice button. An analog temperature sensor in the ice container is connected to the Arduino. A single RBG LED is located in the ice dispenser that will change from blue to red when the temperature gets too warm inside the ice cooler. A full CAD model of the completed device can be found in the Appendix. Figure 1 details the completed device with all of the above mentioned parts and functions. System Details Trunk Figure 1 Finished Leaky Tree with labels for each section

4 User Interface: Figure 2 shows the control panel which contains the LCD screen, the ice button, the scroll buttons, and the on/off switch. When held, the ice button dispenses ice. The scroll buttons change between each drink option on the screen. The selection button dispenses the drink. Inside this box is an Arduino Mega and a similarly sized perforated board. This board contains all of the semiconductors and the PIC. The flowchart that details this system can be found in the Appendix in figures 9 and 10. Figure 2 The user interface is made up of four illuminate buttons and a Red-Green-Blue backlit LCD screen.

5 Ice Dispenser: Figures 3 and 4 detail this system. It contains the servo motor, coupler wire, rotating linkage, augur, 3D printed and tapered ice-limiting slot, ice slide, and ice-melt collection system. The ice dispensing auger is powered by a servo through a linkage. The cooler is made of a 5 inch PVC pipe with a 3-D printed endcap that the ice can slide through. When the ice button is held, the servo is activated and turns 180 degrees. The rotating linkage attached to the servo spins the ice augur, which rests over the ice slot. When the augur is not covering the ice slot, ice will fall down the slide and into the cup. The blue cover over the slide helps to stop the forward motion of the ice, and drop it straight down into the cup. Any water that accumulates on the 3D plate flows to the back, where it is dripped into an additional internal collector. This then empties out to a small, easily accessible receptacle outside of the trunk. The software flow chart shows the sub program that runs this system in figure 9. Figure 15 shows the functional diagram for this system. Figure 3 An RC servo is used with a linkage to drive the auger that dispenses ice.

6 Figure 4 Inside the tree trunk is the ice cooler. This auger is driven by the servo. The end cap is specially designed to allow ice melt to drip into a specific location as well as support the shaft for the auger. Air System: The air tank, in the rear of the device, is filled easily through the Schrader valve to between 80 and 100 psi by the user, as seen in figure 5. From the tank, the air travels through a limiting and relieving regulator, which limits the pressure to 7 psi. The air is then split four ways in a series of T-manifolds and distributed into the inlet of the bottle cap. Figure 13 shows the functional diagram that details how the air and liquid systems interact.

7 Figure 5 A compressed air tank allows regulated air to travel into the bottles. This compressed air is the driving force for the liquid. Liquid Dispensing System: The bottle caps also have straw tubes that run from the bottom of the bottle back up through the cap, as shown in figure 6. These tubes then run into the trunk and out in the front for liquid dispensing into the cup. The black nozzles on the ends allow the liquids to pour directly down into the drink. This system s software flow chart can be found in figure 10 in the Appendix. Figure 14 details how the sonar sensor is used to activate the liquid system.

8 Figure 6 The straw tubes and caps that fit over the tops of the bottles Lights: As the user presses buttons, the coaster under the cup lights up in a colorful pattern. When no cup is sensed by the sonar sensor, it turns red. While the drink is pouring, it changes to green. The lights underneath the tree top are green at all times, and LEDs above each bottle indicate which liquid is dispensing. The ice slide changes colors based on feedback from the temperature sensor. Some of the LEDs are shown in figure 7. The flow chart in figure 10 in the Appendix shows how the LEDs are controlled. Sounds: Figure 7 Several of the LEDs and the coaster lit The speaker is used to alert the user of the various states of the drink dispenser. There is a warning sound for when no cup is present. Also a sound is made at the beginning and end of each drink being poured. The software flow chart for this system is detailed in the Appendix in figure 10. Wiring:

9 Figure 8 shows how all wires exiting the electric panel are wired through a custom channel between the plywood layers of the base to shield them from liquid spillage and improve appearance. They re-surface behind the trunk and are run through a cord-wrap (vine) to the top of the tree. Figure 8 A groove cut under the baseplate houses all of the wires going from the control box to the upper portion of the tree. This accounts for eight LEDs, the servo, temperature sensor and the solenoid valves.