The team at the biggest engineering competition in the world, Formula Student Germany. @FSG

About the Team

FST Lisboa is the Formula Student team from Instituto Superior Técnico, University of Lisbon. 

Since 2001 we’ve been constantly reviewing and refining what we do to deliver the very best output and respond to the demands of an ever-changing Motorsport industry.

Our purpose is to design, build and test formula race cars in order to represent Portugal when competing with other engineering universities at Formula Student competitions.

As up now, we’ve developed 9 prototypes of which the first three were combustion and the remaining electric. For this season, the team has embraced a new challenge: create a fully functional autonomous car with all systems integrated and working consistently, without neglecting the already existent electric project.

FST10d

Concept

The team is adapting last year's electric prototype - FST09e - to empower it with autonomous driving capabilities. Thus, becoming FST10d. The work includes modifications to the mechanical and electronic configuration of the race car in order to successfully pass the demanding technical inspection at the competitions as well as adding sensors and processing units that enable autonomous driving. Furthermore, we have to design actuators - Steering Actuator (STA) & Emergency Brake System (EBS) - to reproduce the pilot's movements and develop software such that these algorithms provide the prototype with vision capabilities, enabling it to sense the environment and locate itself on the track to, in turn, be able to move through the desired trajectory.

All of this requires heavy work by the Electronics department members, which have designed new PCBs as well have been performing maintenance on those of the base vehicle. We would like to count on the support of PCBWay on this endeavor.

Electronics

The major differences to the FST09e concept include changes to the LV System Power Supply and to the Communication Protocol. Let's see the highlights of these changes:

• Power the LV System from a new custom-made independent LV Battery rather than from the team-built 600V Accumulator. This is due to increased power demands, which the current DCDC solution could not handle due to cooling deficits.
• Minor changes to the existing CAN Bus channel to embrace new devices.
• Ethernet and USB communication from LiDAR and Camera, respectively, to the PC.
• Change the Shutdown Circuit (SDC) - required by rules, disconnects HV from any system in the car other than the accumulator when this circuit is open - to go through the Remote Emergency System - an industrial-grade transmitter/receiver.

Have a look at the electronics architecture below.

EBS-NP (Emergency Brake System - Non-Programmable)

Non-programmable Logic used to handle the SDC whose rough logic is given as follows:

ASSI - Autonomous System Status Indicator

This board is located at the sides and rear of the vehicle to indicate the Autonomous System State:

• AS Off - Off.
• AS Ready - Yellow Continuous.
• AS Driving - Yellow Flashing.
• AS Emergency - Blue Continuous.
• AS Finished - Blue Flashing.

DV Feeder

This new PCB serves three main purposes:

1. Power Distribution:
2. STA, PC ,PC Fans.
3. 24V: Solenoid Valve (EBS), Ouster LiDAR.
4. 12V: VLP-16 LiDAR, AHRS.
5. Supervisor EBS:
6. Performs initial checks to EBS.
7. Monitors the system to detect failures:
8. Pneumatic Pressure Sensor - AirTank.
9. Pneumatic Pressure Sensor - Cylinder.
10. Hydraulic Pressure Sensor.
11. Plausibility of sensor signals.
12. State of the RES via CAN.
13. Brings the system to a safe state in case of a single failure.
14. IO:
15. Tractive System External Button.
16. EBS Failure Cockpit Indicator.
17. ASSIs.
18. Autonomous Mission Indicator - 7 LED Display.