Minnesota raced this car at WSC 2017, where they placed 5th. Only 5 Cruiser cars managed to finish the entire race, while all the others dropped down to Adventure class.

Here's a front view

And a side view

They had to add a crush appendage in order to satisfy ASC crush zone requirements, which can be seen below.

Array

They have their array split up into 3 sections—the front, middle, and rear. The arrays normalize along one side of the car, which allows them to better angle the entire array.

Telemetry

They use an XBee to transmit data to their lead vehicle, via a antenna mounted in the interior of their car on their dash. A Python GUI allows team members in the lead car to analyze and view the data.

Motors

At ASC 2018, they raced with 1 Eos I motor and 1 Eos II motor.

Apparently they have a Matlab script that has been handed down that they tune and use for creating their motors.

MPPTs

They use 3 of the Dilithium Power Systems Photon 3 MPPTs that Sam makes.

Strategy

One of our observers during ASC 2018 (Spencer Berglund) had been on Minnesota, and had been working on some code for their strategy team as an alumni. We also talked to him in the Chase Car during the competition about strategy.

Their strategy software consisted of an iterative solver written in C# that solved for the vehicle speed they should target over the remainder of the race via simulation. It took roughly 30 s to compute a result, 2 minutes tops. Most of their effort goes into creating an accurate aero model, which determines how much power they will be consuming at various elevations.

Their simulation also takes into account traffic lights, which is implemented by setting the vehicle's velocity to 0 for a certain amount of time steps. A traffic light is denoted manually via a marker in their list of route coordinates.

They invested some time into writing a genetic algorithm that would supposedly converge to a solution quicker, but they never ended up getting that working.

In addition, they also perform calculations that determine where would be a good location to stop and charge, and weigh the benefits of driving further out of the way to charge vs continuing. According to Spencer, one of the things they look out for is large bodies of water (like lakes), since you can get some additional irradiance due to the reflections off the water.

Interior

Their interior is quite nice.

They have a center console, and an instrument cluster behind the wheel.

Composites

They use carbon fiber and Nomex honeycomb.

Testing

At ASC 2018, we talked to some of their team about how they typically perform testing and race preparation.

Test days are actually a full-day affair for Minnesota. They'd pack everything ahead of time (usually the night before), so that in the morning, they'd just grab all their stuff and toss them into their convoy. Then in the morning, they'd review their goals for the day and everyone's roles/responsibilities, and then head out. At the end of the day, they'd do a team debrief before heading back (ie. were we missing any tools, any problems that need to be addressed, etc.).

They basically had 3 types of test days:

1. Driver Training/Roadside Stop "bootcamp"
2. Rayce
3. Strategy

Driver Training and Roadside Stop "bootcamp" were days where the race crew would practice performing replacements of various parts of the car, and allow drivers to get used to driving their car. One interesting thing is that everyone learned how to do everything—people who typically do Electrical work learn to change tires, and so on. They kind of make it into a competition, and time how long it takes people to perform these tasks. The goal is to spread around the knowledge so that there isn't a Single Point of Failure if that person isn't available. They have pretty big parking lots and test facilities that they could use if they wanted to drive at higher speeds.

Rayce days are days where they would drive a route, and practice the roles that they'd perform in the convoy at ASC/WSC. They did something like this with PrISUm this summer. They created route books that they could use, similar to what ASC gives you, so that they get used to reading turn-by-turn directions. They would also use the opportunity to do roadside stops and practice driver swaps as well. This also allows the car to drive in conditions similar to ASC.

Strategy days were basically when they'd perform car characterization, and drive it at constant speed in order to gather data or perform roll-down tests for their model.