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36 DESIGN007 MAGAZINE I APRIL 2018 while solder joints under high temperature extremes can experience creep strain accumu- lation (Figure 3). Thermo-mechanical Fatigue Solution Depending on the application and the auto- motive company involved, evaluating if an automotive electronic module is susceptible to the thermo-mechanical fatigue issues dis- cussed in items 1-3 would traditionally require 700-1,200 hours accelerated thermal cycling life testing that when combined with other dura- bility evaluations often require 12-16 weeks of testing. These days, physics of failure research has produced CAE tools that accurately perform durability simulations for thermo-mechanical fatigue and other reliability risk issues of elec- tronic products. This results in a virtual reli- ability growth capability that rapidly identifies failure risks that need to be corrected, interac- tive with design creation, that saves the time and high expense of physical durability-reli- ability testing. The use of durability simulation for automotive electronics aligns with the over- all use of CAD and CAE tools in the automotive industry, which have reduced vehicle develop- ment times from five years to 24 months (or less). One example of CAE durability simula- tion tools is DfR Solutions' Sherlock Automated Design Analysis software, which won a "Best of Innovation" award at IPC APEX EXPO 2018. Similar benefits have been reaped in the aero- space industry, which has led the Society of Automotive Engineering and Automotive and Aerospace divisions to collaborate in develop- ing the new standard SAE-J3168 Process for Reliability Physics Analysis of Electrical/Elec- tronic Equipment, Modules and Components. This effort is intended to define best practices for durability simulations of electronic mod- ules and assemblies. DESIGN007 James McLeish is a senior member of the DfR Solutions technical staff. He has 30 years of automotive elec- trical/electronics (E/E) experience, having worked in systems engineer- ing, design, development, produc- tion, validation, reliability and quality assurance of both components and vehicle systems. Autonomy is a much-anticipated feature of next-gen- eration microsystems, such as remote sensors, wearable electronic gadgets, implantable biosensors and nanoro- bots. KAUST researchers led by Husam Alshareef, Jr-Hau He and Khaled Salama have developed small standalone devices by integrating maintenance-free power units that produce and use their own fuel instead of relying on an external power source. Triboelectric nanogenerators (TENGs) capture mechani- cal energy from their surroundings, such as vibrations and random motion produced by humans, and convert it into electricity. In these tiny generators, frictional contact between materials of different polarity creates oppositely charged surfaces. Repeated friction causes electrons to hop between these surfaces, resulting in electric voltage. They incorporated nanogenerator and miniaturized electrochemical capacitors into a single monolithic device encased in silicone rubber. The leak-proof and stretchable shell provided a flexible and soft bracelet that fully con- formed to the body. Fluctuations in the skin–silicone sepa- ration altered the charge balance between electrodes, causing the electrons to flow back and forth across the TENG and the microsupercapacitor to charge up. In addition to exhibiting longer cycle life and short charging time, MXene microsupercapacitors can accumu - late more energy in a given area than thin-film and micro- batteries, offering faster and more effective small-scale energy storage units for TENG-generated electricity. "Our ultimate goal is to develop a self-powered sensor platform for personalized health monitoring," says Ph.D. student Qiu Jiang, the lead author of the self-charging band project. The Raw Power of Human Motion