The Design West conference consists of several subconferences: ESC, Android, Black Hat, Design Med, Designing with LEDs, Multicore, and Sensors in Design.
That means it covers a wide range of subjects, even though the underlying theme is embedded systems. As you know, embedded system environments are drastically different from those of PCs and servers. Their computing resources are very limited in size and power. You need to constantly pay attention to those constraints. One area I focused on in covering the conference was automobile and embedded systems. Luckily, there was a keynote delivered by JB Straubel, the cofounder and CTO of Tesla Motors.
JB’s keynote gave me an excellent view of Tesla’s vision, history, differentiation, and future plans. You may wonder how an EV has anything to do with embedded systems and IT. An EV consists of a lot of components (embedded systems), and all of them are controlled by software. He said people asked him why he did not move his company to Detroit, the Mecca of the car industry. He said it was because EVs require embedded and software expertise and Silicon Valley was the best place to source such talents. So he will stay put in Silicon Valley.
In a different presentation, it was reported that more than 10 million lines of code and about 100 controllers are used to control a Chevy Volt.
This includes many sensors to monitor how the car is operating. This is beyond checking battery level and simple engine oil depletion. The collected information can be used to alert the driver to take appropriate action. For example, each tire reports its pressure, and if it’s low, a low-pressure alarm is generated to alert the driver to remedy the problem. I do not know whether the Roadster and Model S are on a par with Volt in the area of electronic control complexity. Even before the EV era, automobiles were increasingly controlled by electronic systems. In a way, we are driving a computer on wheels. On top of that, with more infotainment coming to cars, the importance of software and embedded systems will increase, for sure. These new trends will generate more data than before to form Big Data. That is another area where IT and software engineers can contribute.
Now back to JB’s keynote speech. His motivation was to contribute to preserving and sustaining the environment. When he looked into oil consumption, he found that the majority of consumption is in the transportation segment.
The slide he presented is based on data that is a little dated, but it is well known that about two-thirds of oil consumption is in the transportation segment. By converting automobiles to run on electricity, we can gain more independence from foreign oil.
Some of the points he made are the following.
Most car manufacturers outsource their parts and components. That is why they are often called OEMs. Tesla insources when possible, as shown below.
The good news for software engineers is that each component will require more software control and, as each component grows in sophistication, more sophisticated software control will be required. This means more demand for software expertise, which means more employment.
Battery technology choice
As is well known, Tesla uses a large number of small batteries to run their motor. The Leaf, Volt, and other EVs and hybrids use bigger batteries. Tesla’s current battery packs weigh about 1,000 pounds and can fuel a motor for 245 miles, while the Volt’s 430 pounds of batteries drive it only 35 miles in all-electric mode. This is very interesting to note. Battery technology is based mainly on chemical reactions but also requires mechanical and software support. It needs climate control to cool or heat the batteries so that the operational temperature range stays in the designated area. Also, charging and discharging need software control to protect batteries. Too much current to a battery at one time would harm or even destroy it, and good control on that is a must.
It is amazing to see how the size of the battery pack shrank in their new design. The new model, Model S, can have its battery laid out flat, as shown below.
Compare it with the Volt’s battery packs (weighing about 430 pounds), shown here.
Tesla’s new Model S will be equipped with its own DC fast charging. There are three different levels of charging for EVs. Level 1 operates at AC 120V and takes 14 to 16 hours for a full charge. Level 2 works at AC 220V and takes 3 to 8 hours for a full charge. Level 3 operates at DC 480V or higher and takes 15 to 30 minutes for a full charge. The Society of Automotive Engineers (SAE) has not finished the level 3 specification. Japan’s CHAdeMO is trying to make itself an international standard, although SAE does not seem to accept it as a standard. Tesla’s level 3 is yet another level 3. Without a standard for level 3, the market will be confused, and consumers may not be encouraged to buy EVs. For more details, see here.
My take on battery technology
No one disagrees that energy storage such as batteries holds the key to a new world order of energy. An EV in particular relies heavily on battery technology for its success. As discussed before, the state of the art needs drastic improvement. The 430 pounds of the Volt’s battery packs sustain only 35 miles of driving, while the Tesla’s 1,000 pounds sustain a 245-mile travel range. Something does not add up here. Tesla knows something that GM does not? I wonder.
JB said that Moore’s law does not apply to battery technology, which improves in density by about 7% annually. And that makes twice as much in ten years. EV1 in 1996 and Roadster in 2006 show this.
Considering all of this, a battery has become a pretty complex embedded system. But if battery technology improves as JB predicted, the EV future may be bright.
He concluded his speech by discussing future plans, as shown below.
The first version was manufactured under several constraints because of body and other suppliers. Once they become a viable company for developing their own versions of components, they can start innovating.
Tesla is without doubt a very different car company and has been doing many unconventional things, such as staying in Silicon Valley and insourcing rather than outsourcing. It has its own DC rapid charging system. I hope they keep their momentum and keep providing unconventional, innovative ideas to the car industry.