Car-Kará Baja SAE

About Our Team

We are a team from Federal University of Rio Grande do Norte, Brazil/RN, formed by undergraduate students who developers a Baja Off-road car to race on Baja SAE competitions every year on Brazil. We are one of the top 10 teams on Brazil, in the last competition (2017), we have placed 5th in overall with a total o 7 trophies. Like the others, events sponsored by SAE, like Formula SAE, Aero Design SAE, we have to develop one embedded system to our vehicle to acquire data, online or offline. We represents our state (Rio Grande do Norte - RN) on national-level Baja SAE competition here in Brasil. All of our team are undergraduate students in mechanical/mechatronics engineering. Also, we are one of the oldest team on Brasil, founded in 1995, we have two national champions (1998 and 2001, first place) and we were the first Brazilian team to win the international Baja SAE competition in 1998. 

About Our Project

For this competition year, we are planning to develop 4 PCB for our embedded system, each PCB (as we call, electronic control unit, or just ECU) is responsible for certain part of the car. For example, the rear ECU acquires the speed and RPM of the car, among temperature and gas level. The front ECU acquires front-suspension positions and minor data. The data logger ECU, as the name says, saves all the data collected and storages on a SD card, and send it via Xbee to a computer in almost-real time.  For last but not least, the steering ECU shows to the pilot all-important data to see on real time race (such as speed and rpm).

As the others SAE Collegiate Design Series, we have to project and build an prototype with some subsystems, including a embedded system. Now, for the embedded system, we've placed the 5th on this subsystem presentation. Some pictures of our embedded system project:

Our dashboard, integrated on carbon-fiber steering wheel, made by us.

Our PCBs for this year has two layers and does not pass the size of 100 x 100 mm; we do our best for developing the smallest and compact PCB for each ECU.

This one is the dashboard ECU, it stays inside the steering wheel, among the display and tachometer. It has a integrated buzzer to alert the pilot in some situations, also it is responsible for receiving data and showing on the 2.4" display. 

In the picture below, we have the rear ECU (top) and the front ECU (bottom). The first one reads speed, rpm and gasoline level on the tank. The second one does many things (we call it the central ECU). One of the most important things that the central ECU does is to send in real time all the data collected from the embedded system to one computer on the team's box (not in picture, but the central ECU also have a GPS integrated).

So, with this electronic, we've placed a top 5 in electronics project and 3th in comfort. But, as you can see, our electronic is very simple, all PCB are one sided cooper and are made by a very poor CNC. For this year project, we are planing to make a step over: starting using 2-layer PCB and some SMD components, and applying a more robust manufacturing, so we can spend more time with actually real test besides spending days searching for a broken trace or bad contact on our CNC PCB. Other thing is, as you can see too, we have a distributed system, and for this year our team are going to race with 2 cars. One goal for this year is testing for real a Centralized Vs Distributed embedded system, therefore, besides the four ECUs, we are projecting a centralized ECU to be installed on our second car.

Some specs of our 2017 PCBs:

 We have maintained the amount of pcbs on the first car ( four pcbs); and for they, these are the specs (with quantity and dimensions) of the boards that we are looking to build through you:

- Datalogger: Qty 5, 2 layer, 70 x 90 mm

- Dashboard: Qty 5, 2 layer, 85 x 50 mm
- Front ECU: Qty 5, 2 layer, 50 x 50 mm
- Rear ECU: Qty 5, 2 layer, 50 x 64 mm

And for the second car:

- Centralized: Qty 5, 2 layer, 86 x 75 mm

We are starting to work with SMD components and 2 layers PCB, but this kind of technology is very scarce on our country, only two or three companies produces 2-layer PCB, but none of them has metalized pin (vias), so it make to us very difficult to work with these technologies.

We hope, with your sponsors, the possibility to improve our embedded system and grow up more and more on our project, to stay as competitive as possible to get the 1th place!

Best regards,

M. Chiozzi

Member of Car-Kará Baja SAE Team
https://www.facebook.com/carkara.baja/?fref=ts