I remember as it was yesterday. It was spring 2011, I was chilling in my new apartment and shuffling channels on my TV.
Discovery, the same program again and again,
Nat Geo, some stupid job, History, Pawn stars – boooring!
HRT-1 (Croatian Channel 1), HRT-2, Nova – what’s this?!
Mean green old BMW 3-Series is drifting, it sounds interesting but...
Where’s the sound?
Some guy, named Mate (pronounced Math-e), my age, is complaining that he was drifting this old BMW and competing in 402 m drag races but the old BMW was constantly broken.
He already destroyed the differentials, transmission (several times), engine, axels, just about anything you can imagine.
At one point he decided to do something radical, he wanted to make it electric.
But why?
Let's analyze the power-torque curves of the typical internal combustion engine and the typical electric motor.
Just in case that this is not self-explanatory to you take a look how inefficient internal combustion engine is.
Actually, it provides the power and torque in only a narrow range of revs.
On the other hand, the electric motor grabs from the start.
How to control the electric motor?
The funny part starts now. Even today you can find the original posts written by Mate on the Croatian forum devoted to electric vehicles (nick CroDriver).
He was a smart kid in school, not with the best grades but smart enough to design the glow-controller and win the national competition. In the land of Nikola Tesla, it’s not easy.
If you want to read more about the Nikola Tesla, check this post written by @maticpecovnik
If you want to control the speed of the motor, you can’t just stick the resistor; it would be wasting of, well, everything.
You need to make the very speed switch, to simulate the frequency. Electric bikes usually use the Hall effect sensor to achieve this.
What about the batteries?
There are two solutions, the impossible one, to buy the battery pack you need, or to make your own battery pack from the little cells, named 18650, that look like this.
Batteries themselves are not the problem, you buy quality batteries. If I remember well, they took a123 batteries.
However, if you want them to be durable, you need good battery management system (BMS). As each battery is unique, during the charging/ discharging, some of the cells could become overheated, too much drained or over-charged.
They developed their own model that concentrated on each cell.
In a very simple form, BMS looks like this:
BMW and the Records
BMW was finally ready, it had 600 HP, was able to do ¼ mile in 12 s, and broke the World Speed Record for the electric cars.
It never becomes easier, you just go faster
Famous cycling quote
In 2012 – 2013 there was the question, what to do next? BMW gave its whole potential, maybe they could build the car?
How difficult could it be? They will buy some components and simply put them together.
They made the list of desired components, mostly trivial components like wipers, sprinkles and similar things. The bill was – with 7 – 8 figures.
They decided to develop all the components by themselves.
To develop all from scratch in Croatia, the country with NO car manufacturers, the country that was the part of Yugoslavia that made – Yugo.
The Team means Everything
Exterial design, Adriano Mudri, interio design ex-Pininfarina Goran Popovic (and a bit help from Vilner)
Electrical motors with the cooling – they will develop by themselves.
Carbon fiber – they will learn how.
And let’s get wild; let’s control each wheel as we want. Calculations could be done 100 times in second and adjust the speed of the rotation. The dream come true, the perfect ”differential”. They call this feature torque vectoring.
The car can be driven like a front wheel car if you don’t have the experience, or can be set in drift mode or whatever you want in between.
Infotainment system – also developed in-house.
Chasing the excellence
I spent some times in Modena, in 2014 and visited all the museums, Pagani, Stanguellini, and on my back home – Rimac.
Just as the simple tourist, with some symbolic fee.
Rimac is stationed in Sveta Nedelja (Santa Dominica, reminds me on Santa Agatha where the Lamborghini works).
Relatively small paved yard encircles the building. Recognizable drifting marks were everywhere; those people know how to fun.
I entered the studio – cute dogs everywhere.
Employees are allowed to take the pets to work, it reduced the stress – nice...
What is that wall, I asked.
That’s the wall of shame, it reminds us of our bad ideas and the progress (Enzo Ferrari had the same...)
We continued to the chassis department, one large desk to be more precise. Paper models everywhere, those are wise and practical people, no fancy 3D printers, just simple old school.
Our chassis consists of XYZ tubes. Actually, 5 less, we have just made the optimization, cheers the guy on the desk.
We proceeded to carbon fiber department. Again, the wall of shame with cracked parts, wrongly layered carbon sheets, and similar things. Those people are progressing by leaps...
Next stop was the assembly line for the Greyp bikes. I was talking to a guy who assembles it.
What devotion, sparkles in the eyes and the proud in his voice. I would let him do the surgery on me.
The final stage, taking the picture and visit of the battery testing area. Look at this thing, do you know what it is? Well, it looks like a giant heater; you are discharging the batteries with this? Yes, we made it!
Perfectly smart, I noticed.
I waved them goodbye, made the tire mark with my Alfa 156 and left knowing that I was the witness of the history
This Spring, expect C-2, whatever C-2 is, but they announced on their FB profile
If you ever see Rimac stocks – buy, that energy and endurance are something valuable
If you have some 100 - 200 BTC, laying around in some digital shed, take one Rimac
It's made by smart, devoted and passionate people
References
https://auto.howstuffworks.com/rimac-concept-one.htm
http://www.bud3.net/2012/05/rimac-concept-one/
https://www.geotab.com/blog/why-hybrid-vehicles-are-more-efficient/
http://www.enginelabs.com/news/new-740-horsepower-ferrari-v12-wins-evo-engine-of-the-year/
http://www.electronics-tutorials.ws/electromagnetism/hall-effect.html
https://www.homepower.com/articles/vehicles/project-profiles/lithium-ion-batteries-electric-vehicles
https://www.topspeed.com/cars/bmw/1984-bmw-e-m3-by-rimac-ar136364.html
http://www.electric-vehiclenews.com/2013/06/rimac-offers-powertrain-parts-to.html
http://archyworldys.com/mate-rimac-the-man-who-tinkers-in-niemansland-fastest-electric-car-in-the-world/
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