Test work with the E0711-9

From mid-May to mid-July, the GreenTeam focused on testing its new electric racing car. To participate in the Formula Student competitions as competitively as possible, the team finished an extensive test program with the E0711-9. Day and night shifts were utilized to make the best possible use of the limited time. While the test team covered as many kilometres as possible with the E0711-9 the car was then prepared by the service shift during the night.
In the beginning, the system had to be basically made operational. This also included important stress tests, e.g. for the suspension. The reliability of the racing car, as the results of the past clearly show, is a key element for a successful season. The stress tests were followed by setup work. Ultimately, this is a matter of finding a compromise that gives the drivers the necessary confidence to find their personal limit to push the car. The team completed a distance of nearly 700 kilometres before heading to the first event of the season.The team is optimistic about the season. “The tests were satisfying and we achieved a good mileage”, says team leader Matthias Bildersheim. “The atmosphere in the team is positive and we are looking forward to the upcoming events.” (Photo © Max Partenfelder)

FS Austria Results

The second Formula Student event of the season took place in Austria from July 29th to August 2nd. A strong starting field with a total of 49 vehicles (19 electric cars) fought for points and podium finishes at the Redbull Ring. Once again, the GreenTeam scored convincing results in the statics disciplines, with the victory in the Business Plan Presentation being the standout result. In the dynamic disciplines, however, the team experienced ups and downs. The density at the top was really close, but the team nonetheless achieved Top 5 results in the Autocross and Acceleration. A thrown cone in the Autocross and the resulting two seconds penalty prevented an even better placement.

With the final endurance still to come, the GreenTeam was still in contention for a podium position, even the overall victory did not seem to be out of range. But unfortunately, shortly before the Top 3 shootout of the electric class startet, rain hit the track. In wet track conditions both riders lost more than 20 seconds a lap to the top times. Once again, the Green Team was unlucky. This time, however, it was the weather that prevented the team from celebrating a podium position. In the end, the GreenTeam had to settle for sixth place overall. (Photo © FS Austria Media)

 

FS Austria Results:

Discipline:

Cost Report:
Business Plan:
Engineering Design:

Acceleration:
Skidpad:
Autocross:
Endurance:
Efficiency:

Overall result:

Points:

93,0
75,0
125,0

67,8
50,3
78,5
122
92

698,5

Place:

5
1
4

3
7
4
7
2

6

We congratulate the team of the TU Hamburg for the victory at the Formula Student Austria. Second place was taken by Team Racetech (TU Freiberg) and third place by the team of Chalmers University of Technology.

FS East Results

The Formula Student East at the Zalaegerszeg Automotive Proving Ground in Hungary was the GreenTeam’s first race for the 2018 season. After achieving very good results in the statics, the team was able to win the first three dynamic disciplinces Acceleration, Skidpad and Autocross and claim the maximum number of points. However, an unfortunate technical failure at half-time of the final endurance prevented a podium finish in the overall standings. Since up to 425 points were awarded in the Endurance (together with the Efficiency rating), some points were missing to reach the rostrum in the overall standings. In the end, the GreenTeam had to make do with sixth place overall.
The GreenTeam congratulates Formula Student Team Delft on their victory, FS Student Team Tallinn on second place and Racetech Racing Team (TU Freiberg) on third place. (Photo © FS East Media)

FS East Results:

Discipline:

Cost Report:
Business Plan:
Engineering Design:
Overall Statics:

Acceleration:
Skidpad:
Autocross:
Endurance:
Efficiency:
Overall Dynamics:

Overall result:

Points:

89,0
73,0
142,0
304,0

75
75
100
DNF

250

554,0

Place:

3
3
2
2

1
1
1


6

6

Season review – Part 4: Formula Student Spain 2017

After winning the Formula Student Germany in Hockenheim, the GreenTeam could travel to Barcelona with a little less pressure. The Formula Student Spain in Barcelona marks the end of the season and therefore having fun is always a little more pronounced than in the other events. “In a way, it’s a little more relaxed,” says Philipp Mayer. “But of course you still want to achieve the best result possible.” At the same time, it is also an attempt to give the upcoming team leader of the new season some of the responsibilities to guide the handover.
“Zurich (AMZ Racing) was incredibly good in all disciplines. In some disciplines they pulled huge gaps”, remarks Marko Nonhoff to sum up the event. Surprisingly, most of the teams had no problems with the heat and and their cooling systems and thus, there was a close fight behind AMZ Racing for the remaining podium places which the GreenTeam could win in the end. “Second place was another sensational result”, emphasizes Philipp Mayer. Four competitions, four podium places, including two victories: this is the extremely thriving season résumé at the end of the 2017 season – a very successful year that the new team wants to build on with the upcoming E0711-9.

The GreenTeam starts its 2018 campaign on July 18th. By then, team and vehicle have to prove their skills at the Formula Student East in Hungary.

Review: Rollout 2018

GreenTeam, RennTeam and GreenTeam Driverless presented their current Formula Student racing cars to the public on May 4th. The E0711-9 is a consistent evolution of its successful predecessor. The first race is scheduled for July 18-22 at the Formula Student East in Hungary.

The brand-new E0711-9 relies on the same monocoque shape that was already the basis of its successful predecessor. The colouring, however, is chosen even more aggressively. The last white surface on the front of the vehicle has now given way to the dark, shiny carbon fibres.
No one in the team wanted to rest on last year’s success, quite the contrary: the 35 or so team members have shown their full commitment over the past few months to further optimise the concept and get the most out of each individual component. Stagnation is ultimately a step backwards in a competition that depends on hundredths and thousandths of seconds. And the competition is growing from year to year.
With around 1000 spectators, the Carl-Benz Arena was filled to capacity for the presentation of no less than three cars. In addition to the GreenTeam, the RennTeam and the GreenTeam Driverless also presented their new racing cars. There was a crackling tension in the air before the unveiling of the vehicles. Different videos presented the three teams, but also the Formula Student competition format with its different static and dynamic disciplines.

Unveiling of the vehicles is the highlight

But the highlight of the evening is of course the unveiling of the three Formula Student cars. Until then, the main protagonists stood on stage covered by cloths and illuminated in the respective team colour. For the team members who worked on the cars until shortly before the presentation – time is always short – there was a small moment of relaxation that could be enjoyed together with family and friends. The rollout is an important step on the way to the competitions, but should also be a platform to thank the sponsors, partners and supporters without whom racing cars at such a high technical level would not be possible.
After the show, big grapes form around the new vehicles: everyone wants to see the racing cars up close and take a closer look at the important details, such as the suspension system with two separately working springs.
Even if the visual proximity to the predecessor is obvious, larger differences are noticeable. These mainly concern aerodynamics. The details on the side boxes appear considerably more complex and the rear wing has an additional element introduced. “You can be proud of what you have achieved”, says team leader Matthias Bildersheim to all the team members. “We are looking forward to the coming season, but at the same time we still have to put in a lot of energy into the upcoming test phase.”

The Rollout in picutres:

Re-live Rollout 2018

The rollout of RennTeam, GreenTeam and GreenTeam Driverless is now available in full length on YouTube.
On May 4, the three teams presented their vehicles for the new season to the public in the Carl-Benz Arena. Besides the presentation and introduction of the new Formula Student racing cars, the recording provides insights into the work in the team, the rules of Formula Student and the cooperation with sponsors and supporters.

Link to the video

Preview: Rollout 2018

As of yet, the members of the GreenTeam have been working for almost eight months on their new vehicle for the 2018 season. Construction and conception,  production of the parts and the assembly of the car are subject to a strict deadline: the official rollout on May 4, 2018. Until then all screws and bolts should fit. In the best case, the first system tests have already been completed as well. Thus, the team can start the first test drives immediately after the rollout.
The rollout is a first real highlight and an important stop on the way to the Formula Student competitions which take place in July and August. The team needs enough time between the rollout and the first event to sort out possible problems and prepare for the various dynamic disciplines.

Three teams, three cars
This year’s rollout sticks to the tradition that GreenTeam and RennTeam present their new racing cars together. The GreenTeam was once founded by former RennTeam members. The joint building, which the two teams have moved into this year, has further intensified the cooperation. The combined rollout underlines the close connection between the two teams.
2017 was the first year in which Formula Student competitions were held for autonomous vehicles, too. Alumni and members of the support association went on to found the GreenTeam Driverless which now acts as a subteam of the GreenTeam with its own sponsors. The basis of the autonomous racing car named E7001 is the 2016 seaon’s vehicle, the E0711-7. All three teams are going to unveil their vehicles on May 4.

To get to know the history of the GreenTeam the former racecars will be shown in the foyer of the Carl-Benz Arena. You can follow the “heritage” from our first electric car, the E0711-1 (2010), which still had a lattice tube frame, to the former world record vehicle, which accelerated from 0 to 100 km/h in 1.779 seconds, to the winning vehicle of the 2017 season. The increasingly complex aerodynamic packages are certainly the most conspicuous. Wings, deflectors and diffusers now generate an immense downforce. Combined with the active torque distribution on the four separately driven wheels, the Formula Sudent vehicles of the latest generation achieve extremely high cornering speeds.
The GreenTeam aims to build on last year’s successes with its new E0711-9. However, the rollout is only a first step to maintain the team’s goals. The real potential of the new electric car can only be seen in direct comparison with other competing teams. After all, they too are continuously developing their vehicle concepts and trying to get every tenth of a second out of their cars.

Pictures of the 2017 Rollout:

Season review – Part 2: Formula Student Austria

The victory at the Formula Student East event came with great surprise for the whole team. But the fantastic result in Hungary also led to rising expectations for the upcoming competitions in Spielberg, Hockenheim and Barcelona. Unfortunately, an isolation fault which the team detected just the day before its departure to Austria caused a small delay. Luckily, the scrutineering in Austria was not a problem for the then well-prepared car and thus, the dynamic disciples were not influenced negatively.

The team scored good results in the static disciplines. Second place in the costreport and first place in the business plan ensured an excellent position, with the dynamic disciplines still to come. The first dynamics were acceleration and skidpad. The continuous improvements throughout the four acceleration runs helped to score a satisfying third place. Skidpad was even better. With an advantage of over one tenth of a second, the GreenTeam achieved another first place and thus 75 points.

Hit by the rain

“A small rain shower was forecasted for the afternoon session with the autocross coming up”, remembers Philipp Mayer. However, the team was hit by surprise: heavy rain that pelted down way earlier than expected. The Autocross even had to be interrupted. Until then the GreenTeam had only set one lap time. With 45 minutes to go, the race control decided to reopen the racetrack. But the track did not dry out completely in the remaining minutes. No improvements were possible. Although the Autocross did not go according to plan, the result was nevertheless respectable: once again a third place. Nevertheless, the team lost some points to its competitors, especially AMZ Racing (Zurich) who dominated the autocross with a superb lap time.

With the endurance coming up three teams could still hope for the overall victory: AMZ Racing (ETH Zurich), KA-RaceIng (KIT) and the GreenTeam. The weather on race day was incredibly hot. Many teams feared cooling problems and accordingly the failure rate was high. Only

five teams completed the full race distance of 22 kilometers. Due to the oil cooling, the GreenTeam however hoped to have an advantage over its competitors. But right after the start, the GreenTeam car suddenly stopped. A system reset was necessary and costed a lot of time. In the second half of the race the engines cut out again. As a consequence, the car had to be driven with rear-wheel-drive only. “We were still able to post competitive lap times, thanks to a strong driver performance”, says Philipp Mayer. But the problems eliminated all chances to claim the overall victory. Nevertheless, the team could score a podium finish yet again. “The third place was a strong result”, concludes Philipp Mayer. “But with the almost perfect display until the endurance, it felt a little disappointing.”

ZF Teambuilding: Winter In the Black Forest

Our second teambuilding, organized by ZF, took place in the black forest from January 10 to 12. The team members were challenged with many tasks and problems which could only be solved through cooperation and with team spirit. “We grew together as a team,” says project manager
Matthias Bildersheim in retrospect. The ability to work in a team is important for the upcoming season and it is a central component, if you want to be successful.

In contrast to the daily routines in the GreenTeam workshop, the team members spent a lot of time in the countryside. Thus, to experience the winter landscape of the black forest the team went on a snowshoe hike to the top of the Feldberg which was both, exhausting and rewarding at the same time.

The goal for the teambuilding was to try and prepare our team members for the forthcoming challenges during the fabrication of the new car and the Formula Studen competitions. “All in all, the teambuilding was pretty cool and helped us to focus on our future work”, says Matthias Bildersheim who is looking forward to the new season with confidence.

 

Season review – Part 1: Formula Student East

Going into the first event in Hungary, the team was quite sceptical due to problems during the testing periood. Nevertheless, the team wanted to face the competition with high spirit. The first event is always an indicator for the following competitions; as it is hard to predict in advance the performance of the car and the team.
The team handled the statics, i. e. business plan, cost report and design event, very well and placed themselves just behind Delft in second place. They even managed to build a small point gap to other favorites such as Zurich and Karlsruhe. The results of the dynamic disciplines skid padd, acceleration and autocross were extremely close. Given the announced rain, timing was extremely important. Since the two drivers nominated for each discipline have only two runs each, the teams try to get the best track conditions possible. As the weather conditions changed rapidly, luck became a decisive factor. Delft managed to put in a final run right before the end of the session. After all their struggles on this day it was quite surprising that they pulled off a fantastic laptime and finished in second place. In doing so, they pushed the GreenTeam back to third place at literally the last second of the session.

Decision in the endurance
The overall results were nothing but set in stone with the endurance still on the line. Delft, Karlsruhe (KA RaceIng), Zurich (AMZ) and the GreenTeam were still in the run for first place. The tension was at its high peak when a rain break interrupted the endurance. Whereas the GreenTeam and KA RaceIng fought for every tenth of a second, Zurich had to retire its car. Delft had problems as well. Therefore, they lost a lot of time. The GreenTeam and Karlsruhe stayed head-to-head throughout the entire distance, so that the number of thrown cones and the respective penalty seconds decided the results. Predictions were too close to call. It was not until the award ceremony that the tension was released. The GreenTeam was able to cheer twice: Victory in the endurance and as a result of that the overall victory in Hungary. “This was an outstanding result, especially regarding the expectations we had in advance”, explains Philipp Mayer. “Not only the car, but the team worked as well. That was very positive.”
Only the boldest optimists had expected a victory in Hungary Especially after a problematic test period. The team was all the more delighted about the very strong start to the season.

Review: The E0711-8

One central criterion for a successful Formula Student season is the reliability of the racing car. The Endurance, a 22-kilometre endurance race with driver change, is by far the most important discipline in terms of points. Together with the efficiency score, which is linked to the Endurance, 425 of the total of 1000 points are tied to the endurance test. Accordingly, a failure is painful and almost always prevents a top ranking. The reliability of the E0711-8 at the decisive moment – the car saw the chequered flag in all four Endurance runs – was the key for the success in 2017.

Overall, the E0711-8 can be described as a successful evolution of its predecessor, explains Philipp Mayer. “There was nothing conceptual that we couldn’t put into practice. One of the reasons for this was that we were able to use well-functioning parts from the old vehicle.” Thanks to countless test kilometres, the team was also able to sort out the initial reliability problems. Although it didn’t really go according to plan, the E0711-8 covered 600 kilometres up to the first competition. But the effort should pay off in the end.

Highlight:
The E0711-7 was the first vehicle in the Formula Student Electric field to rely on a completely oil-cooled accumulator. The oil cooling showed its great potential in the course of the 2016 season, but still needed to be optimised. One of the drawbacks was the excessive oil demand, which the team was able to reduce substantially for the E0711-8. “We use the battery container as an oil container and flood it with oil. In this way, we cool cell tabs and pouch bags at the same time”, explains Max Partenfelder. This solution – a consistent evolution from the previous year – also allows the cells to be pre-treated and the Endurance to be started with less internal resistance. While the battery in the E0711-7 was still divided into two parts and integrated in the two side pods, the team returned to a single battery in the 2017 season that sits behind the driver. The aim of this design change was to reduce the moment of inertia, to enable a more compact package and to reduce the weight at the same time.

 

Go-Karting – who is fastest?

What happens when engineers and technicians reach into the steering wheel themselves? So if – to put it bluntly – they are driving a car instead of building one? The competitive streak of some of the team members, who fought for the fastest lap times during our karting competition, was clear to see.
In Neckartenzlingen, 21 team members ventured with the 6.5 hp karts on the wavy and 315-metre-long track which comprises eight left and seven right bends. Two qualifying sessions determined the grid for the two races and divided the 21 drivers into two groups. The time of the fastest lap decided the sorting of the grid. However, compared to the faster drivers, the second grid offered fairer motorsport: clean overtaking manoeuvres and finely fought duels characterized the race.
In Grid 1, on the other hand, the drivers drove more aggressively and fought hard for their positions.

Since the dynamic disciplines of a Formula Student competition are also determined by the talent of the drivers’ pool, go-karting is also regarded as the first step to decide the driver selection. Thus, it is not a pure fun event.
Clear favourites for the seats of the Formula Student racing car could not yet emerge. However, further comparative runs are already planned.