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2017 Cruiser Class Summaries

2017 Cruiser Class Summaries

Day 7: Practicality Judging

Dr David Snowdon, A/Prof Peter Pudney

Efficiency scores for RACV Cruiser Class were determined as the cars arrived in Adelaide on Friday. The remaining component of the score for each Cruiser was judged in Adelaide’s Victoria Square on Saturday. The judging consisted of two parts with equal importance for the score -- a set of exercises, and a subjective view by a panel of four judges.

Each car performed two common maneuvers: a parallel park and a three-point turn. They were scored on the number of attempts required to complete each exercise. The teams were also asked to show how their cars could fit a rear-facing child’s seat, a baby’s pram, and a full-size bicycle. The latter proved particularly challenging, with each successful team elucidating an enormous cheer from the crowd assembled.

The panel of four judges included Hans Tholstrup, founder of the Bridgestone World Solar Challenge, Andy Sampsons, a senior Ford Australia engineer, Takashi Tamomoto, Chief Marketing Officer of Bridgestone Corporation, and Rani Snowdon, a high school English teacher.

The judges were chosen to offer a range of diverse views on the cars, and were asked to judge the with criteria which was derived from a typical car review including cabin space and comfort, features, ease of operation and desirability. The over-arching question is: which car would you buy or recommend?

The teams put on a show -- quite literally in the case of Bochum, whose team pitched their car’s features from the point of view of two tourists travelling the Australian outback. Likewise, Iowa State University aimed to garner the judges’ attention by offering beer from an esky in the vehicle’s storage space.

Some cars were designed for different markets -- TAFE SA presented a solar powered truck, which can tow a six metre trailer, and even includes a sleeping cabin appropriate for a person up to 2 m tall.

Sometimes the little features stood out the most. One team used their cup holders to hold cup-a-noodles, complete with chopsticks. Some cars included central locking. Several teams’ car sound systems kept the mood light with an eclectic mix of music.

Innovation abounded. Team Eindhoven built an app that integrated with the car to select the sunniest parking spot, suitable for charging the car in time for the next use, as well as using the car’s battery to power a smart home at night. Arrow demonstrated a solar array which they’d developed to be tough -- they rested a bag on their solar array, while other teams defended the fragile solar cells. The team from Iowa had put work into developing cool mesh seats, which impressed all of the judges.

Compared with previous events, the cars’ interiors have evolved enormously. Teams like those from UNSW, Bochum and Eindhoven got a special mention. Bochum used environmentally sustainable materials in the construction of their car, including recycled material from previous solar cars.

All teams that entered the RACV Cruiser Class were judged for their practicality, and they are included in the rankings below in the order of their practicality score.

The columns are:

  • C: cabin space and comfort
  • F: features
  • E: Ease of use
  • D: Desirability
  • W: Wildcard
  • J: Judge’s total score, out of 50
  • T: Three-point turn
  • R: Reverse park
  • S: Storage
  • E: Exercise total score, out of 50
  • Score: Final practicality score, out of 100.
 

Team

Name

C

F

E

D

W

J

T

R

S

E

Score

1

40

Solar Team Eindhoven

8.8

9.8

8.7

8.3

8.0

43.4

3

3

3

50.0

93.4

2

11

HS Bochum SolarCar Team

7.8

8.5

8.7

9.3

7.5

41.7

3

3

3

50.0

91.7

3

75

UNSW Solar Racing Team Sunswift

8.0

8.8

8.3

8.0

8.0

41.1

2

3

2

38.9

80.0

4

09

PrISUm

8.0

7.3

7.3

6.0

6.8

35.3

2

3

3

44.4

79.8

5

45

Lodz Solar Team

7.0

5.3

5.0

5.5

6.3

29.1

3

3

3

50.0

79.1

6

42

TAFE SA

5.0

5.0

5.3

3.7

3.7

22.6

2

3

2

38.9

61.5

7

94

University of Minnesota Solar Vehicle Project

6.5

5.8

6.0

6.0

5.0

29.3

3

2

0

27.8

57.0

8

30

Clenergy Team Arrow

7.5

8.3

6.7

7.8

8.0

38.2

0

2

1

16.7

54.8

9

05

SunSPEC

5.5

4.3

3.0

3.8

1.7

18.2

2

3

1

33.3

51.5

10

14

Flinders Automotive Solar Team

3.0

3.3

3.3

2.0

1.7

13.3

1

3

2

33.3

46.7

11

35

IVE Solar Car Team

3.3

4.0

4.0

3.5

2.7

17.4

2

2

1

27.8

45.2

12

95

Apollo Solar Car Team

4.0

4.0

4.3

3.3

2.7

18.3

1

2

1

22.2

40.5

13

49

STC-2 Nikola

4.0

3.5

4.0

3.5

2.0

17.0

1

2

1

22.2

39.2


And so the final scores and ranks for the 2017 RACV Cruiser Class are:

Rank

Car Number

Team Name

Efficiency Score

Practicality Score

Total Score

1

40

Solar Team Eindhoven

80.0

20.0

100.0

2

11

HS Bochum SolarCar Team

32.0

19.6

51.6

3

30

Clenergy Team Arrow

20.6

11.7

32.4

Day 6: Port August to Adelaide

Dr David Snowdon, A/Prof Peter Pudney

Today was the last day of the event for the Cruiser class, who had to reach the Adelaide control point by 2 pm today. There’s no advantage to arriving early, but an enormous impact if late — non-completion of the event.

As a result, the remaining six teams were on high alert today. For Apollo, it was clear that the goal was unachievable — they would have had to have driven more than the speed limit to make the distance in time.

For Eindhoven, Bochum, the task seemed very achievable — each requiring an average speed less than they have already achieved over the event. For Bochum, matters were complicated when a motor controller malfunctioned just short of the finish. They were able to drive to the control point and complete the event.

For Minnesota and IVE, it was far less clear cut. Minnesota would need to have averaged around 86 km/h, which, when contending with Adelaide traffic, really means driving at around the speed limit. IVE had a more reasonable target of 69.3 km/h.  Unfortunately neither team was able to make the distance in the allotted time. IVE finished just 18 minutes after the 2 pm deadline, and Minnesota finished 54 minutes later. As a result their efficiency scores are zero and Arrow takes third place.

And so we have the final efficiency scores for the RACV Cruiser Class of the 2017 Bridgestone World Solar Challenge. Eindhoven has an unassailable lead, with over 2.5 times the efficiency of Bochum and a full 80 points, Bochum on 38 and Arrow on 20.6.

Eindhoven have carried an average of 3.4 people over the 3021 km, using 45.7 kWh of external energy. By comparison, a Tesla Model S85 (85 kWh battery) has a practical range of about 400 km. It’s a phenomenal achievement by the team.

Tomorrow is practicality judging for all of the Cruiser cars. There are another 20 points up for grabs, but it is unlikely that these will change the rankings of Bochum and Arrow.

image1

Day 5 - Coober Pedy to Port Augusta

Dr David Snowdon, A/Prof Peter Pudney

On the penultimate day for the RACV Cruiser Class vehicles, the pace has become all-important. The cars must reach the finish line in Adelaide by 2:00 pm, or will otherwise be non-competitive. Based on the last positions reported by the Coates Hire Car Tracker, the teams have between 307 km and 734 km left to drive: 

Team Number

Team Name

Distance Left (km)

Required Speed (km/h)

40

Solar Team Eindhoven

307

55.0

11

HS Bochum SolarCar Team

248

41.3

94

University of Minnesota Solar Vehicle Project

473

86.0

35

IVE Solar Car Team

381

69.3

30

Clenergy Team Arrow

307

55.8

95

Apollo Solar Car Team

734

146.8

Cars that have been driving more slowly (Minnesota and Apollo) are going to have to drive quickly in order to hit the 2 pm deadline. In the case of Minnesota, driving slower has allowed them to attain a good energy score, currently in third place. However the team will not make it to Adelaide by the deadline without substantially speeding up.

Apollo would have to travel at nearly 150 km/h -- way beyond the speed limit, guaranteeing that they will not complete the distance within the allowed time. Arrow, Eindhoven, Bochum and IVE all look to be reasonably safe with respect to the deadline.

Bochum have increased their hold on second place, and so with the scores and ranks becoming apparent, the cars to watch tomorrow are Minnesota and IVE -- if they can finish the event by reaching Adelaide by 2:00 pm, then they will retain their position. If they fail to do so, Arrow will take the bronze.

Day 5 chart

Day 4: Alice Springs to Coober Pedy

Dr David Snowdon, A/Prof Peter Pudney

Day 4 in the RACV Cruiser Class event proved to be a further challenge for many, with cloud and rain increasing their reliance on external energy. As a result we’ve seen a few different strategies.

Eindhoven and Bochum both reduced the number of people carried for a portion of the day -- the first time Eindhoven has carried less than their maximum capacity of five, with just the driver in the car into Coober Pedy. All other teams except Apollo have also run with just one person.

Eindhoven’s strategy seems to be to recharge each night, and adjust their energy use by reducing the number of people to match the available energy from the sun to ensure that they meet the deadline of 2 pm on Friday.

Unsurprisingly, all cars charged the battery overnight.  

There were some saving graces for day 4 -- a substantial tail wind and a break in the cloud cover later in the day meant that several teams sped up to use the available energy.

Eindhoven’s efficiency advantage of nearly three times the competition seems unassailable. Meanwhile, there is a battle for second place. Bochum’s high speed used a lot of energy, and at the Kulgera control point they had dropped from second to third place behind Minnesota in the all-important efficiency score. They then put four people into the car to Coober Pedy, which put them back into second place. Minnesota’s challenge is the pace -- they are a long way behind the average speed required to reach Adelaide by the Friday 2 pm deadline, and will have to use more energy to catch up to complete the event.

It is worth putting the achievements of these vehicles into context. The goal is to move people across Australia as efficiently as possible, measured by the number of person-km per kilowatt-hour of external energy. The only production electric vehicle with the range to practically do so is the Tesla Model S. Analysing how the Tesla Model S would perform in the Cruiser Class, the difference is clear: the Tesla has an efficiency of 29.4 p-km/kWh. Eindhoven manages 270 p-km/kWh -- over nine times the efficiency. These highly efficient Cruiser vehicles are nearly an order of magnitude beyond the current commercial offerings.

PR-oriented version for 1630 event time:

In the RACV Cruiser Class, the rain and cloud has reduced their solar power and so teams have reduced the number of passengers they are carrying in their cars. Eindhoven dropped from five to one people in the car for the first time, which reduced their overall efficiency score, but they are still a long way ahead of the rest of the field with almost three times the efficiency of the next best competitor.

Day4 chart scaled 

Meanwhile there is a battle brewing for silver and bronze. Bochum’s high speed has used a lot of energy, and during the day they dropped from second to third place behind Minnesota in the all-important efficiency score. They then put four people into the car to Coober Pedy, which put them back into second place. Minnesota is a long way behind the pace required to reach Adelaide by the Friday 2 pm deadline, and will have to use more energy to catch up.

Day 3: Barrow Creek to Kulgera

Dr David Snowdon, A/Prof Peter Pudney

The 2017 Bridgestone World Solar Challenge is proving to be a tough event, for all classes. Cloud and rain have reduced the energy produced by the cars’ solar panels, and so the RACV Cruiser Class cars have relied more on their batteries and external charging. The pace has become all-important -- teams that fall too far behind and are unable to catch up have dropped out of the Cruiser competition. The Australian outback has proven too much for some cars. UNSW suffered a suspension issue and retired from the event.

As a result, the rankings changed significantly. Aside from Bochum and Eindhoven, all teams still in the RACV Cruiser class are carrying just one person and are up to an hour behind the pace required. They will be attempting to conserve their energy and catch up over the next three days.

Every team filled their battery pack last night.

Currently in second place, Bochum has used nearly double the external energy of Eindhoven to Alice Springs -- 44 kWh -- and are using that energy to catch up and then push far ahead of the pace, arriving in Alice Springs more than an hour ahead of what’s required. This could be part of a strategy to reach sunshine sooner (to reduce external energy use), or the team could be counting on the ability to drive slower later in the event and run more efficiently that way. Either way, Bochum’s large battery and daily charging (so far) has led to a large external energy use.

The clear leader in this event continues to be Eindhoven, arriving precisely on the pace in Alice Springs, having carried five people all the way from Darwin (7465 person-km), and having the second lowest external energy in the remaining field.  

Cruiser - day 3 efficiency

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Day 2: Daly Waters to Barrow Creek

Dr David Snowdon, A/Prof Peter Pudney

Day 2 in the RACV Cruiser Class yielded new insights into the efficiency of these brand new vehicles. As teams arrived at Daly Waters, we learned whether the team had elected to charge their battery overnight using external sources.

The relative efficiency score of Cruiser teams depends not only on how well the team is doing, but also on how well the best team is doing. When Eindhoven reported that they had charged overnight, the scores of all other Cruisers increased. But as the other teams reported that they had also charged, their scores went down again.

Every team charged overnight. They would have been glad of their decision, as cloud covered the route. The weather forecasters predict more inclement weather over the next few days, which means less energy from their solar arrays.

The Bochum and Lodz teams both resolved issues with their cars and ran much faster to make up lost time. At the Tennant Creek control point, Eindhoven, Bochum and Arrow were all ahead of the pace. The rest of the field will have to work harder (and use more energy) to get to Adelaide by 2 pm on Friday..

So far, the highest scores are from cars carrying four or five people. Eindhoven, capable of carrying five, is in the lead, with UNSW and Iowa State (each carrying four) sitting in second and third. UNSW is ahead of Iowa due to their choice of a smaller battery pack (meaning less external energy used). Two seat cars such as Arrow are struggling to keep up, using more external energy for fewer people transported.

One team increasing its rank substantially is Bochum who, having resolved some issues with their electronics, transported one person to Katherine, then two people to Daly Waters and then four to Tennant Creek. While they’ve used a significant amount of energy to do so, it will be interesting to see how far up the ranks they can get before the end of the event.

Looking ahead to Day 3, the pace will start to matter more - teams will need to increase their speed to get to Adelaide in time, and with the rain and cloud cover, it may be necessary to carry fewer people to do so. With about half the field having passed Tennant Creek, the next control stop is Barrow Creek—cars on the pace will arrive at 10:18 am - where the teams will check in and we’ll discover whether the Cruisers will charge every night.

Day 1: Darwin to Katherine

Dr David Snowdon, A/Prof Peter Pudney

The RACV Cruiser Class is about building efficient, practical cars. While it's important for the cars to get to Adelaide by the end of the event (Friday, 2 pm), the outcome of the event is determined by how many people can be transported, for the least amount of external energy. Teams may choose to re-charge their car's battery from an external source, but this will reduce their score. Teams may also choose to transport more people, which will increase the score.

On Day 1 of the 2017 Bridgestone World Solar Challenge we've seen that this is far from a solved problem. Today the configuration of the cars became apparent (see the attached table).

Some cars are capable of carrying five people (allowing for many people to be transported), others are only capable of carrying two (resulting in a lighter car).

Even more varied is the battery mass, and the consequent energy stored in the battery.
Each time a team re-charges from an external source, it is assumed that the team have added a full charge -- increasing their energy use. The size of the batteries varies wildly - STC-2 Nikola carry just 6.1 kWh, compared with 16.3 kWh for the Apollo team.

The last important factor to consider is the 'pace' - the average speed required to arrive in Adelaide by the curfew of 2 pm on Friday afternoon. Teams ahead of the pace may be able to later slow down to conserve energy. Teams behind the pace will need to use more energy to catch up. This pace gives only a rough guide to how teams should be proceeding - teams might also vary their speed to improve the operating efficiency of their car, or to maximise the amount of sunlight they collect.

Eindhoven's Stella Vie dominated Day 1 of the event, arriving at the Katherine control point at 1:29 pm - one minute ahead of the pace - carrying five people over the 322 km distance (1610 person-km), the maximum of any team in to Katherine. All other teams that arrived at the control point were behind by up to an hour, and will need to use more energy to catch up (although the start procedures and Darwin traffic may slowed some teams). The teams carried between one (HS Bochum) and five (Eindhoven) people, with most carrying between two and four. Lodz out-performed several teams who carried more people due to their smaller battery pack (which means the car has used less external energy so far).

While we've now discovered how many people the teams intend to carry, we still do not know how often they will re-charge, and this is key to their efficiency. When the teams arrive at the Daly Waters control stop, around 8:30 am on Monday, their official observer will report whether the team re-charged the car's battery during the night. If teams are able to avoid that external energy use by relying on their solar panel, they'll have a critical advantage in the days to come.

Team

Name

Seats

Battery Mass (kg)

Battery Specific Energy (Wh/kg)

Battery Capacity (kWh)

Battery Capacity per Person (kWh/kg)

05

SunSPEC

2

57.9

250

14.5

7.2

09

PrISUm

4

45.0

250

11.3

2.8

11

HS Bochum SolarCar Team

4

58.8

250

14.7

3.7

14

Flinders Automotive Solar Team

3

118.7

250

29.7

9.9

23

University of Tehran Solar Car Team

4

96.6

250

24.2

6.0

30

Clenergy Team Arrow

2

61.0

250

15.2

7.6

35

IVE Solar Car Team

2

30.3

250

7.6

3.8

40

Solar Team Eindhoven

5

30.5

250

7.6

1.5

42

TAFE SA

2

119.0

125

14.9

7.4

45

Lodz Solar Team

5

29.0

250

7.2

1.4

49

STC-2 Nikola

2

24.6

250

6.1

3.1

75

UNSW Solar Racing Team Sunswift

4

42.3

250

10.6

2.6

94

University of Minnesota Solar Vehicle Project

2

27.0

250

6.8

3.4

95

Apollo Solar Car Team

2

65.2

250

16.3

8.1