Applied Electrical Engineering Education Leads to Beer Pong Table with Flare

It would be a mistake to make light of a University of Cincinnati student project to re-engineer the beer pong table.

That’s because the project by third-year electrical engineering major Cameron Hoerig, 21, of Upper Sandusky, Ohio, involves applied electrical engineering lessons that will integrate with Hoerig’s coursework and already applies to his required

cooperative education

(professional work) quarters.

Said Hoerig, “Whether I’m working for a co-op employer in order to envision and re-engineer the controls on a hospital bed or I’m re-engineering the beer pong table, the challenge is the same. I want to build circuits that perform specific tasks.”

It’s just that one will impress his peers a bit more, which was part of his initial motivation for re-engineering the beer-pong table: “I wanted to build something that would show up my friends majoring in business.”

Hoerig began working on the project in August 2010 while on a cooperative education quarter. Co-op is the practice wherein students alternate quarters or semesters in the classroom with quarters or semester of paid, professional work related directly to their majors. UC is the global founder of co-op, having begun the practice in 1906 and today houses the nation’s largest co-op program at a public university. The co-op program at UC is ranked in the country’s top ten by U.S. News & World Report.

WHAT THE RE-ENGINEERED BEER PONG TABLE DOES

Hoerig has made use of numerous  electrical engineering tools and components – like a micro controller, shift registers, photo cells, light-emitting diodes (LEDs), resistors and ten light-sensitive LED rings (each composed of eight individual LEDs) that are placed at each end of the table. In the middle of each ring is a light-sensitive photocell. So, when a cup is placed on the sensor, a software command turns on and “rotates” the LEDs, providing for the appearance of light spinning around the cup.

UPCOMING PLANS: LIGHT ARRAY TO TRACK TRAJECTORY OF PING-PONG BALL

Next, Hoerig plans to place an LED array in the middle of the table so that it will light up with just the motion of a hand over the table. That will serve as a precursor to a major improvement he plans to complete next year wherein a LED array in the middle of the table will light up to match the trajectory of the ping-pong ball.

He’ll do that by mounting a camera on the table’s edge. That camera will track the ball’s trajectory and send that information to the LED array.

“The best part of that will be actually getting it done and working. The most challenging part will be getting all the components to work together, to get the hardware and software interfaces right,” he said.

FOR TECH TYPES OR IN CASE YOU WANT TO DO THIS AT HOME

As  mentioned, on either end of the table are 10 LED rings composed of eight LEDs each. In the middle of each ring resides a photocell. Each photocell is connected in series with a 1kO resistor from +5V to ground, creating a voltage divider.

 The voltage across each sensor is sent to an analog input on the pic16f887 MCU and into the ADC. The program polls each sensor, compares its ADC reading to a reference value, and decides if that particular ring should be turned on or off. So long as a ring stays lit, the software will “rotate” the LEDs.

Each ring of LEDs is driven by an 8-bit serial-in, parallel/serial-out shift register. The software will send

out 10 bytes of information using 2-wire SPI. Each byte simply states which LED is on, if any, and the

byte order specifies the rings.

The power for the circuit comes from an AC/DC adapter purchased from Radioshack (SKU: 273-316). A power connector was positioned on each end of the table. These are connected to one another by a power and ground wire running the length of the table.

The reference value for the ADC readings was something that was found with a little math and a little

trial-and-error. In some situations, the same ADC reference may not be suitable for all sensors since the

photocells are not completely consistent relative to each other.

The software is capable of comparing each ADC reading to a unique reference value for the corresponding ring. Because of this, there are three lines in the function “Analyze ADC” that need to be uncommented.

The software was written in MPLAB in conjunction with a PICkit 2 for programming the MCUs.

• Apply to UC’s undergraduate electrical engineering program.