Formula Student Team Delft
Newsletter
Design Presentation Special
Formula Student Team Delft
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Drivetrain
Chassis and Suspension
Formula Student Team Delft
Dear reader,
F
irst of all, we would like to wish you the best for 2015. We recently had our production kickoff, so some DUT15 parts have already been made! So at the time you are reading this, the team is vigorously machining metal and laminating fiber sheets to realize their designs. In this Design Presentiation Special we want to both inform you about the evening of the design presentation and, in particular, present to you the DUT15 design! Among the featured designs are the drivetrain that drives
Powertrain and Electronics
the car, the chassis that protects the driver, the suspension that provides a smooth ride, the aerodynamics that keep the car on its track, the powertrain that powers the car and the electronics that control the car. Enjoy reading the third edition of this newsletter!
Kind regards, Stijn Pennings Team manager
Aerodynamics
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Formula Student Team Delft
DUT15 Core Team
Guest speaker Lennart Verheij
Len: “The chassis is like a sandwich�
Drink at the D:Dream Hall
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Drivetrain
Chassis and Suspension
Formula Student Team Delft
O
n Thursday evening the 18th of December the design presentation of the DUT15 was held at the Aula of the TU Delft. It was the first official event of the season. Our team manager Stijn Pennings hosted the evening. He enthusiastically explained what Formula Student is all about and showed what the team has done and accomplished the last couple of months. During the interlude, guest speaker Lennart Verheij demonstrated what a business presentation for the Formula Student competition is like. He and Sander Vlot will represent the team at the business presentation events this summer. Next, it was up to Chief Engineer Len van Moorsel to reveal the DUT15 design. He vividly illustrated all functions and features of the car.
After the presentation, Alex van Koppen was brought to the stage to thank him for all his work, as he had helped us right from the start with the DUT01. Therefore, he is now a honorary member of FS Team Delft! The evening ended with a drink and tours at the workshop. Hundreds of friends, relatives, sponsors and other supporters attended the presentation live. Additionaly, over 1.600 interested people have watched it from elsewhere through the livestream connection. In case you have missed it, you can still view it HERE. Thanks again for the massive support!
Alex van Koppen becoming honorary member
Powertrain and Electronics
Aerodynamics
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Formula Student Team Delft
Drivetrain
Comparison of DUT14 and DUT15 innerwheel concept
DUT14 and DUT15 brake systems
DUT15 transmission
DUT15 tires
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Drivetrain
Chassis and Suspension
Formula Student Team Delft
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et’s start with the drivetrain design. The drivetrain is “like a woman’s hand bag,” as Chief Engineer Len van Moorsel noted in the design presentation. This is because there is a seemingly endless amount of space inside. This space is efficiently used for the DUT15 innerwheel concept, which is an improved design with respect to the previous DUT14. One example is that the tires have been improved to be even more durable. With an outer diameter of 368 mm, they are still extraordinarily
Powertrain and Electronics
small compared to standard racecar tires. Moreover, the gear ratio of the transmission has increased. That way, the single stage gears are able to create even higher forces. Furthermore, the brake callipers have been reduced in size, leading to a significantly smaller wheel hub (i.e. spindle). On the left and in the background, the difference in size between the DUT14 (left) and the DUT15 (right) is clearly shown. All these refinements sum up to a significant weight loss and lead to a faster car.
Aerodynamics
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Formula Student Team Delft
Chassis and Suspension
The chassis
Several driver protection systems 8
Drivetrain
Chassis and Suspension
Formula Student Team Delft
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lthough the wheel can accommodate many parts, it cannot give shelter to the driver, unfortunately. Therefore, the chassis department offers him the protection needed. This year, they again succeeded to do this and, keeping in mind the lightweight design philosophy, added only the weight of a beer crate. They did this by using what is informally called a sandwich structure. That is, making use of two layers carbon fiber-reinforced polymer with an aluminium honeycomb core. The two structures are both lightweight, but not very stiff. Combining them, however, makes them unimaginably
Powertrain and Electronics
strong and stiff. Likewise, combining bread and toppings makes an unimaginably delicious sandwich. But this is not where the story ends: the chassis and wheels should be connected by means of a suspension design. For the positioning of the connecting rods, the suspension department took 103 refining iterations for their final design. This is almost twice the amount of improvement steps compared to last year’s design! By the way, one rod is designed to be able to lift an elephant without breaking.
Aerodynamics
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Formula Student Team Delft
Powertrain and Electronics
The accumulator
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The motor controllers
The electromotor
Drivetrain
Chassis and Suspension
Formula Student Team Delft
T
cornering performance, allowing even faster turns.
The available energy is efficiently used by adding systems like regenerative braking. The motor controllers smoothly regulate this process. They also operate slip ratio control and yaw rate control. In short, those systems enhance the
Furthermore, electronics are the assembly that control the car and act like the human nervous system. The car’s sensors collect data, which is then sent via the wiring (shown in the background) to electronic control unit (ECU). The ECU thus recieves, processes and transmits information, just as a human brain would do. Furthermore, the electronics department implements all kinds of safety systems to keep the driver free from harm. For example, the accumulator management system (AMS) constantly monitors the temperature and voltage of the accumulator cells. It is worth mentioning that all software as well as hardware is self-designed.
he powertrain provides thrust, the power to go fast. It consists of accumulator, motors and motor controllers. Energy to drive the four electromotors is stored in the accumulator below the driver. In total it can store 7.2 kWh electric energy, which is 12 percent more than last year’s car. This is enough energy to power a mobile phone for three years straight! What’s more, due to the application of lightweight lithium polymer (LiPo) cells, the complete accumulator assembly only weighs about 40 kg.
The control panel
Powertrain and Electronics
The electronic control unit
Aerodynamics
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Formula Student Team Delft
Aerodynamics
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he final featured design is the aerodynamics design. It consists of four main building blocks: a front wing, a rear wing, sidepods and an undertray. The four elements act just like wings on an airplane, except they produce downforce instead of lift (i.e. buoyancy), so that the car stays on the ground in corners, even at high velocities. More specifically, they generate more grip between tires and track. In general, more downforce means faster cornering abilities.
100 km/h DUT15 driving upside down at 100 km/h.
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Drivetrain
Chassis and Suspension
Formula Student Team Delft
This year the Formula Student rules for aerodynamic design have been made even stricter, so the aerodynamics department had a tough job reaching a reasonable amount of downforce. Nevertheless, they were dauntless and performed so well, that the car could potentially drive upside down at a speed of 100 km/h. New this year, is that the front and rear wing are unsprung mass. That is, they are connected directly to the wheels, instead of being indirectly linked to the sprung chassis. It takes a lot of computation power to come up with a reasonable
Powertrain and Electronics
aerodynamic design. We have utilized a cluster of 36 computers performing Computational Fluid Dynamics (CFD) models.
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ow that we roughly discussed most parts of the car, it is time to take a look at the bigger picture. This has been the first official event of this season, but there are more to come. The next big event will be the DUT15 Rollout, so come see the newborn DUT15 make its first meters in Delft on Friday the 5th of June! Until then, we will keep you updated on our production progress, not only through these newsletters, but even more frequently through social media shown at the last page.
Aerodynamics
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Formula Student Team Delft
a d va n c e d
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lightweight engineering
Drivetrain
Chassis and Suspension
Formula Student Team Delft
Powertrain and Electronics
Aerodynamics
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Formula Student Team Delft
General info Contact details Department
Phone number
Address
Electronics & Powertrain Suspension & Vehicle Dynamics Chassis & Aerodynamics Team Manager & Chief Engineer Operations Manager & Technical-Finance Manager
+31 152 787 008 +31 152 788 436 +31 152 787 007 +31 152 788 891 +31 152 787 531
Stevinweg 1 2628 CN Delft The Netherlands
Important dates Friday the 5th of June DUT15 Roll out in Delft
Next edition Production progress update
From the 9th till the 12th of July FSUK at Silverstone, UK From the 28th of July till the 3rd of August FSG at Hockenheim, Germany
Social
From the 10th till the 13th of August FSA at the Redbull Ring, Austria www.FSTeamDelft.nl info@FSTeamDelft.nl
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