Maria Montero

An EV made to demonstrate motion control: the mCar …

Monolithic Power Systems wants optical encoders to run for their money. The MPS mCar EV demo showcased motion control and angle position sensors in electronics 2018.

At electronics 2018, there were several automotive-focused demonstrations at the stands, sometimes even displays of luxury F1 cars sponsored by electronics companies. Among them was a unique non-car-focused display – an electric vehicle specifically designed to demonstrate motion control and angle sensors.

Monolithic Power Systems isn’t necessarily the first company that comes to mind when you think of electric vehicles, especially the veritable sea of ​​advertisements for electric vehicles and automotive-related products in electronics or other popular shows. Yet the mCar, the MPS demonstration, was sitting at their booth, an undoubtedly interesting electric vehicle with spinning wheels crawling across the showroom floor.

The free roaming mCar on the MPS demo video.

MPS mechanical engineer and lead designer of the mCar Aaron Quitugua-Flores explains that the mCar is the brainchild of CEO Michael Hsing. Apparently Hsing loves vehicles and determined that a custom EV would attract the attention of MPS. The problem, of course, was that MPS did not have the required machine shop to develop such a project.

So Quitugua-Flores was simply hired to build one.

Over the past year and a half, a team built a mechanical workshop in San José and designed, manufactured and created the electronic integration for the mCar, in partnership with a China-based team that handled the motor control aspects.

The mCar, in general, represents an extremely ambitious project to develop an EV to demonstrate products that do not necessarily have EV in mind.

The mCar making donuts with its tires turned inward in the MPS video

So if MPS isn’t what comes to mind when one thinks of automotive, how does mCar fit into electronics? MPS is no stranger to energy-related components, infotainment systems in the auto industry, but nothing that Quitugua-Flores calls a “macro-scale.”

“We’ve had a number of people ask, I am assuming jokingly, ‘Can we buy the car?'” He says. “And that’s part of the reason we wanted to build something like this. We wanted people who don’t necessarily know what MPS does to be able to come in and start a conversation.”

While MPS is not trying to sell a car, the mCar shows several features that one may need in their own applications. In addition to showing the main components of MPS (power regulators, voltage regulators, voltage converters, etc.), the mCar hopes to demonstrate two main functions:

  • motor control elements
  • angular position sensors

Intelligent motor control modules

The mCar displays various smart motor modules. These include a BLDC motor coupled with an integrated control module already connected to the motor. “With that,” adds Quitugua-Flores, “we have a rotor position sensor and a field-oriented control integrated on the same chip. The associated board, also mounted on the motor, includes motor drivers and a local MCU. The goal is to make application integration very agile. “

An engine control module in the mCar.

The initial developments of the mCar included only magnetic angle detection, but the current iteration shows the integrated magnetic angle detection with the control of brushless DC (BLDC) motors. In essence, it shows the ability to “control everything together” in one package.

Although smart motors are not ready for the automotive space, BLDCs are becoming more dominant in many other applications, such as robotics.