1. Possible imaging methods for the project are
microwave, hyperspectral, ultrasound, and
radio frequency imaging. All four of these
imaging methods are already being used in
the food industry for quality control. [2, 3]
Considerations for the imaging system are
power consumption, cost, and size due to the
fact that this device is aimed to be a small
kitchen appliance.
The closed loop system implemented by the
design will integrate image and temperature
sensors monitor the interior of the egg and
the ambient temperature of the cooking
environment.
The system utilizes a proportional-integral-
derivative (PID) control on the temperature of
the cooking environment.
The results of the ANSYS Workbench simulation of the simplified egg case proved the
assumption to use Transcendental Equation over Lumped Capacitance Method to be
correct. With probes, temperature is shown to lag the most the farther the positon gets from
the egg’ making the .center the last place to reach a steady state temperature.
0 10 20 30 40 50 60 70 80
0
20
40
60
80
100
120
Time (s)
Temperature(°C)
Temperature Vs. Seconds
Center Probe Probe 1 Probe 2 Probe 3 Probe 4 Probe 5
Figure 4. ANSYS Workbench simulation of the internal temperature of a simplified egg..
Since the assumptions held true for the simplified case, the same is true for the oblong case.
By nature, the coldest point at anytime in the egg during heat transfer should be at the center
off the egg, which the simulation proves. There are temperature gradients throughout the
geometry but heating propagates uniformly throughout its duration.
0 10 20 30 40 50 60 70 80
0
20
40
60
80
100
120
Time (s)
Temperature(°C)
Center Temp of Oblong Egg Over Time
Figure 5. ANSYS Workbench simulation of the internal temperature of an oblong egg.
Temperature is transduced
using a precision 10K Epoxy
thermistor. Temperature is
then adjusted by the control algorithm.
Current prototypes accomplish temperature
adjustment via a programmable servo motor
which adjusts the hotplate’s continuous
rheostat.
The autonomous preparation of an egg has
been attempted commercially using open-loop
timer systems which do not offer significant
precision. Technology is now available to
enable creation truly autonomous food
production systems. This project aims to
address the issues of precision and
repeatability present in claimed "autonomous"
egg preparation systems using a modern, low
cost, energy efficient design. A successful
design will adaptively control the cook time and
temperature regulation throughout the
preparation of an egg. To realize this, a
mathematical model to govern the biophysical
behavior of a heating egg as well as a reliable
method to image beneath the egg’s shell and
monitor internal consistencies are needed.
Our mathematical model analyzes the simple
case of heat transfer within an homogenous
sphere submerged in hot, stagnant water
using a transcendental equation.
𝜃𝑠𝑝ℎ =
𝑇 𝑟, 𝑡 − 𝑇∞
𝑇𝑖 − 𝑇∞
= 𝐴1 𝑒−𝜆1
2 𝑟
sin(𝜆1 𝑟 𝑟0)
𝜆1 𝑟 𝑟0
, 𝜏 > 0.2
Figure 1. Using ANSYS Workbench, the mathematical
model was analyzed by applying convention at the surface
of a 10°C sphere submerged in 100°C water bath.
Figure 2. The same analysis applied to oblong geometry.
Incredible Edible Egg Cooker
Daniel Douglas, William O’Mullan, Kimberly Ruff, Dana Joaquin
Joseph Picone, PhD
Temple University, Philadelphia
[1] Naghshineh-Pour, R., Williams, N., & Ram, B., (1999). Logistics issues
in autonomous food production systems for extended duration space
exploration. ACM, 1253–1257.
[2] A. Manickavasagan and H. Jayasuriya, Imaging with electromagnetic
spectrum.
[3] M. Aboonajmi, A. Akram, T. Nishizu, N. Kondo, S. Setarehdan and A.
Rajabipour, ‘An ultrasound based technique for the determination of
poultry egg quality', Research in Agricultural Engineering, vol. 56, no. 1,
pp. 26-32, 2010.
The final design for this project will consist of:
• Apparatus that can provide an environment
with uniform heating to cook the egg
• Hyperspectral imaging system with candling
to monitor egg interior
• A PID controller for temperature change
within heating apparatus
Other major design considerations are:
• Size: small kitchen appliance (i.e. toaster,
coffee maker)
• Cost: affordable for consumers ($50 - $100)
• Power consumption: at most 2000 W
Since heating and electricity are involved, the
design addresses user safety features that will
prevent burns, scalds, shocks, and other
potential injuries.
Analysis
Methods and ResultsIntroduction
Conclusion
References