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PROJ01: Process Document
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Due: 4 Oct 2019

PROJ01: SafeCup

Members: Douglas Pan, Kyle Trieu, Sia Chang, Stephanie Claudino Daffara, Yakira Mirabito

Designing for Emerging Technology, Fall 2019

Project Description

SafeCup is an interactive lid that keeps your drink safe while out. Spend less time worrying and more time enjoying yourself. The SafeCup experience starts when a bartender ID’s you, links your ID to the cup, and then pours you your favorite drink. Cheers! Next, lock your cup by the click of a button on the top of the lid. Wander away and upon returning, simply show your ID to your cup’s camera and it will unlock. If foul play by an unwarranted stranger occurs, LEDs with light up and flash, alerting those nearby. The idea was generated by a team of design students after observing the counter at the bar on a busy weekend night--folks often have to step away to use the restroom, chat with other friends or dance, leaving their drinks unattended.


Project Description        1

Index        2

Observations        3

Design Process        4

Concept brainstorming (9/18)        4

Converging ideation and implementation (9/23)        5

System integration and refinement (9/25)        7

System integration 2 (9/27)        9

Future Iterations        10

Appendix: Instructable style process document step by step making of the work        11

Intro        11

Parts        11

Digital Files        11

Steps        11

Links        16


Location: Coin Op Arcade Bar

Duration: 2 hours

Stakeholders: Bartenders, customers, bar manager

Problem: Leaving drinks unattended. Heightened alert of watching your drink.


Key insights:

Design Process

Concept brainstorming (9/18)

During class, we discussed the basic requirements for the project and generated two concepts as shown in Fig. 1. The cup idea was generated based on observations a few days prior. However, the interactive tip jar served as a design alternative that also focused on the bar counter but could extend beyond a bar setting.

1) a cup for while out at a bar

2) interactive tip jar

Fig. 1: Two concepts generated in-class brainstorm

Converging ideation and implementation (9/23)

This work session served as a key decision-making point. The concept surrounding keeping your drink safe was deemed more impactful and thus as a team, we headed in that direction. We sought advice from the professors regarding utilizing a cup or storage device that bars would install.  Upon deliberation, we ultimately ended up with the decision of an interactive lid.


As a team we hashed out the overall features of the lid that we would like to incorporate, then assigned specific components each person owned.

Fig. 2: Whiteboard space for questions and division of labor

Fig. 3: (Left to right) LEDs on lid, locking mechanism, and external housing

External lid design - Yakira

Fig. 4: Image of the final external lid in Fusion

LED light system - Kyle

Open & close mechanism - Sia

ID reader and Raspberry Pi integration - Stephanie and Doug

Fig. 5: Stranger peeking into the cup with an “angry” face which prompts the cup to blink red.

System integration and refinement (9/25)

Integrating each individual component revealed new challenges. First, the servo motor was free-standing, which meant it was tricky to secure the lid. This was addressed by modifying the inner lid to hold the servo in place. This component was 3d printed rather than laser cut (as in the previous edition). The servo could be attached securely as shown in Fig. 6, and allows for proper travel of the lock. Note the tab that rotates was laser cut with clear acrylic.

Despite this new challenge, the functional prototype worked. For the next iteration, we needed to simplify the design, remove bulky features and approach it with a more aesthetic eye.

Fig. 6. Updated open-close mechanism

System integration 2 (9/27)

During this work session, we tested all the improved parts and integrated all the subcomponents as shown in Fig. 7. The parts seamlessly fit together as shown in Fig. 8. One should note while this edition housed many of the electronics inside, future iterations would include more compact electronics that could fit right on the lid.

Fig. 7: Second iteration of the open/close mechanism

Fig. 8: Cup with all interactive components

Future Iterations

The current iteration of SafeCup focuses on the basic functions of ID recognition, locking, unlocking and visual notification to the bartender. This set of features is designed to improve the experience for the person at the bar.

Barring concerns about personal and data privacy, we see the SafeCup improving in several ways to increase adoption by businesses.


  1. Software features
  1. Patron and drink analytics. The SafeCup could provide bar owners data about age/gender/race along that is tied to drink selection/frequency. This would make it easier to quantify decisions around drink promotions, menu size, seasonal trends in order to maximize profits.
  2. Bar liability. In many states, bars are responsible for serving a drunk person who then causes an accident. However, training and enforcement of this is not uniform across all bars, or even amongst bartenders. The SafeCup could reduce the risk that a bar takes in serving customers by automatically cutting off a patron once some set limit is reached.
  1. Hardware features
  1. Easy to clean. In order for a business to adopt the SafeCup, its life cost (acquisition + maintenance) must be low. The next iteration of the SafeCup would look at mean time-to-failure, and ease of cleaning the lids. While the SafeCup creates a safer drinking environment, it would be disgusting to be handed a dirty SafeCup. The SafeCup lid must be as easy to clean and handle as the bar’s glassware.
  2. Different form factors. We would also look at different form factors in order to maximize use. Bars stock a variety of glassware for different drinks. The SafeCup must be versatile so that it can be used with the most common types of glassware.

Appendix: Instructable style process document step by step making of the work


This document covers step by step assembly and function of the SafeCup


1 Raspberry Pi

1 Crickit Hat for Raspberry Pi

1 NeoPixel LED strip (10 LEDs)

1 Raspberry Pi Cameras V1

1 Pushbutton

1 External Lid (3D printed)

1 Upper Lid (3D printed)

1 Closure Tab (Laser Cut)

1 MG966R Servo

4 10-24 3/4IN Socket Cap Screw

Digital Files



Acrylic Piece:


  1. 3D print/laser cut parts
  1. Print external lid

Fig. A1: Model of external lid in Cura

  1. Print center of the lid

Fig. A2: Model of inner lid in Cura

  1. Laser cut closure tab component

Fig. A3: Clear closure tab (already adhered to inner lid component)

  1. Assemble the upper lid
  1. Attach camera to middle lid component

Fig. A4: Camera inserted to inner lid component

  1. Attach lid closure tab to servo

Fig. A5: Closure lid attached to servo and servo attached to inner lid

  1. Secure servo to holder in middle lid component
  1. Note: Secured using 4x 10-24 3/4IN screws

  1. Assemble the external lid
  1. Add LED around external lid

Fig. A6: LEDs adhered to external lid design

  1. Add pushbutton on handle of cup

Fig. A7: Lock button adhered to external lid design

  1. Assemble the external lid and upper lid
  1. Attach middle lid to external lid

Fig. A8: Inner and external lid components integrated

  1. Assemble the Raspberry Pi + Crickit Hat
  1. Wire up Raspberry Pi and Crickit Hat


Fig. A9: Raspberry Pi and Crickit Hat

  1. Attach portable power source

  1. Put all subassemblies together

Fig. A10: Electronic components (excluding servo motor)

Fig. A11: Finished design (all electronic components housed inside)

  1. Update the software on the Raspberry PI

Fig. A12. Cup flashing green lights  indicating either that it has registered a new ID or that it has identified a correct ID




Landscape image


Modeling Files