WATERLOO — Airlines lost his suitcase more times than he can remember, so Kal Sobel and his team of mechatronics engineers invented one with special sensors so it can be closely tracked with a smartphone.

Sobel, Stephen Kraemer, Bilal Maassarani and Bryan Nagallo are applying for a patent and aiming for a startup based in the Velocity Garage in the Communitech Hub in downtown Kitchener after graduating next month from the University of Waterloo.

Sobel's team calls their invention "casesensitive," and it was among 31 projects developed by this year's graduating class of mechatronics engineers on display Friday in the university's Davis Computer Centre.

"The idea came when my laptop screen shattered when it was in my suitcase and I thought: 'There has to be a better way,' " Sobel said.

The team developed what they call the integrated-sensor package that is built into the suitcase, taking up less than five per cent of the space. It also has four "weight feet" that alerts travellers before arriving at the airline check counter if their bag is too heavy and they must pay extra. The sensor package is linked to the traveller's cellphone.

By tapping on the app, travellers quickly learn exactly where the suitcase is located. Is it on the right plane? Is it on the wrong plane? It will even tell you if it is in another city.

"If somebody has opened it, it will tell you when and where it has been opened," Sobel said.

Sobel signed a contract with Apple and is off to California next month. After that contract is over, he may rejoin his team in a new startup that will try to bring casesensitive to market.

Among the other fourth-year projects is an inexpensive alternative to the unmanned aerial drone, a kit for making robots, a device that automatically balances the electricity usage in a house, a motion-capture system that can be used in animation or for teaching robots complex movements and a stationary mountain bike equipped with 3D goggles for getting exercise.

Cyclus — virtual reality mountain biking — was developed by Leigh Pauls and his team. Cardio exercise is important, but too often it is boring. So they built a stationary mountain bike that includes a set of 3D goggles to give the rider some of the sensations of peddling over trails.

The stationary bike is equipped with a motor and a flywheel that creates resistance for the rider when going up hills or over rough terrain. The gear shifters, brakes and seat are the same as a real mountain bike.

"So the whole mountain bike will move beneath you, and you wear virtual reality goggles," Pauls said.

"As you peddle onto the flywheel, you actually feel the true experience of riding a mountain bike — in any environment you want," Pauls said.

Mechatronics is all about computer-controlled electrical-mechanical systems.

The mechatronics engineering program will be doubled in size in the coming years. It is among the most successful programs at the university. Graduates routinely get hired at some of the most famous tech companies in the world — including Google and Apple — or start their own businesses.

The founders of some of the most high-profile startups in this region — Clearpath Robotics, BufferBox and Thalmic Labs — are graduates of the mechatronics program.

"The mechatronics program has the highest demand of all the engineering programs at the moment," said Jan Huissoon, who chairs the department of mechatronics and mechanical engineering. "It is terrible to turn away students with a 94 per cent average."

Currently, about 125 students are admitted every year. During the next six years, that will expand to about 210.

The first intake was in 2003. The first graduating class was in 2008.

"This is our sixth graduating class now," Huissoon said. "They get snapped up. Most of the students have jobs before they leave."

He is amazed by what the graduating students accomplish with the fourth-year design projects.

"It is almost as if it is a competition: which class produces the most spinoffs every year?" Huissoon said.

tpender@therecord.com