Next Stop: Transportation Research Center

Mary has left the building!

She was shipped earlier this week to the Transportation Research Center in Ohio where she will be inspected by the Safety Tech team. The team is inspecting the entire car to make sure components and subsystems are integrated safely. They will also look to confirm that there are no risks for damaging things like high voltage (HV) cables, coolant lines, etc.

Mary being loaded up for shipping.

Additionally they will inspect the functionality of some safety systems such as our HV ground fault detection, emergency stops (E-stops), charging the HV battery pack and common vehicle functions (horn, lights etc.). Our team will be arriving on site Sunday, and will be able to fix any of the issues the safety inspectors find.

Once we fully pass the inspection we will then be able to move onto the Emission Testing Event where we will set Mary up on a chassis dynamometer — essentially a treadmill for cars. This will allow us to test her different drive cycles and see what kind of tailpipe emissions she produces.

“As a whole, this event allows us to see how well Mary lowers her emissions compared to the stock vehicle” said HEVT team leader Eli White. “It allows us to tweak our control code to change some operating points of components within the vehicle to continue lowering emissions.”

Mary will be returning home to the Ware Lab around March 16th.

Vehicle Mounts Refined for Year 3

This was a very busy week for Mary the Malibu! We have been inspecting many of the mounts found in our vehicle. We’re doing this to either improve their design or to remake them out of aluminum to shave of some pounds.

The mount to the high voltage distribution box (HVDB) has been redesigned and is now made out of aluminum. Just as it sounds, the HVDB is responsible for distributing the high voltage electricity from the lithium-ion battery modules to the high voltage components under the hood. The HBVD also got a new home and was moved to the top of the P2 inverter to increase serviceability.

New HVDB mount.

We have also been redesigning our Bursa mount, which is found in the trunk of the vehicle. It's responsible for changing the current of charge to the energy storage system. The former mount was made of steel, so we redesigned it and made it out of 6061 T6 aluminum instead! The final product shown on the right.

We are now trying to think up ways to redesign the Micro Auto Box Controller (MAB), which was donated by sponsor dSPACE. The former mount was made out of heavy steel, but with the use of the PlasmaCAMM cutter, we are prototyping ways of light weighting this mount. There isn’t a final product yet, so stay tuned!

Be sure to like us on Facebook and follow us on Twitter for day-to-day updates and progress.

Do you have any experience with light weighting? Help us by leaving a comment below.

Build Upate 2.3.14

Virginia Tech may have gone on Christmas break, but many team members stayed hard at work in the Ware Lab. They spent the majority of their time working on getting an engine test stand operational. The goal of this task was to validate our engine controls and to improve the engine harness by rewiring several of the signals. Task completed.

After the engine was rewired and it was working on its own, we added our custom P2 generator motor to the stand. Then we added the wiring for the inverter to the engine harness. Validation complete.

Wiring harness for engine test stand.

What’s next?!

Over the course of the next week, we plan to add the transmission, the third and final piece of the front powertrain, to the test stand as well. We also plan to validate more of our front powertrain controls and determine whether we have solved our transmission leak issue we've been having.

Once we can check off those tasks, the powertrain will be reinstalled into Mary and she will finally be ready to roll as a charge-sustaining hybrid!

HEVT Gets an Early Christmas Present

Sometime over this past summer, our vehicle, Mary the Malibu, developed a ground fault that crippled our ability to run in EV (electric vehicle) mode. We spent roughly four months troubleshooting, but we recently received an early Christmas present — a running vehicle!

I repeat: Mary is mobile!

We were able to find an issue with our rear traction motor inverter and have it sent off to UQM for repairs. After getting our inverter back we were able to re-integrate it into our vehicle to use our high voltage system to run the rear traction motor. Being up-and-running again in EV mode is a huge step in the right direction. We'll now be able to do some vehicle testing and collect a lot more data. We'll be using this data to refine our control code and increase EV efficiency.

Where do we go from here? I'm glad you asked!

Our next major milestone is to get our front powertrain working. As discussed in an earlier post, we have been troubleshooting a fluid leak with our P2 generator motor. We have since narrowed down a few options and are collaborating with headlining sponsor GM to see which stock components may be conflicting with our system.

Next step is to validate our engine controls outside the vehicle using an engine test stand. We will first re-wire the engine on the test stand and then verify certain controls. Once we have done that, we can add our P2 to the engine and test that. Finally, we will add our transmission to the mix and test the engine system fully.

Once we can validate our complete engine components, we should be able to re-install our engine into Mary and run our front powertrain. This will give us our as-intended final product — a running series-parallel plug-in hybrid electric vehicle!

Be sure to like us on Facebook and follow us on Twitter for day-today updates and progress.

Have any ideas or advice for vehicle testing? Let us know in the comments below!

Alumnus Puts Training To Work With Proterra

Over the years, many of our graduates have gone on to do great things in engineering. The real-world experience gained from HEVT is always helpful in their new careers—none more relevant than 2012-2013 electrical subteam leader Brian Kelly.

Brian gives a thumbs up working in the Ware Lab.

Since graduating May 2013, Brian has been working with Proterra as a mechanical engineer. For those who don’t know, Proterra is the world's-leading manufacturer of zero-emission electric buses. They are also a bronze-level sponsor of EcoCAR 2. Brian’s experience with HEVT has given him a range of skills to use in his work with Proterra.

“I am in charge of all of the mechanical subsystems of the high and low voltage modules of the bus,” Brian said. “EcoCAR 2 helped me get a lot of electrical experience. I now know what conditions need to be met on both the electrical and mechanical side.”

Since Brian works on an all-electric bus as a mechanical engineer, he is a sort of hybrid himself. His co-workers jokingly call him a “mech-elec,” meaning mechanical electrical engineer. He is using a lot of CAD to work on designs for the newest version Proterra’s electric bus. He is in charge of all of the mechanical subsystems of the high and low voltage modules of the bus. If an electrical component needs a place to be mounted, he designs a way to integrate it.

“As the electrical subteam leader, Brian was in charge of all of the vehicle’s electrical work including the high and low voltage systems, said HEVT team leader Eli White. “This was majorly focused around the high voltage A123 battery pack we installed into the rear of our vehicle, which powers the rear traction motor.”

His experience working with high voltage electrical systems has been integral in his success with Proterra. Being a mechanical engineering major, he had very little knowledge of electrical systems before his work with HEVT. Brian leveraged his experience and networking from EcoCAR 2 to land his current job with Proterra. 

Brian says it best, "There is no doubt in my mind that I wouldn't be where I am today without my involvement with EcoCAR 2."

Do you or someone you know have a similar success story? Tell us all about it in the comments below!