Cirrus Traffic - The idea

Cities should use groups of UAVs to study traffic, provide useful real-time information about traffic, and find and ticket dangerous drivers. There are already UAVs that stay airborne for two weeks at a time. These low maintenance UAVs are perfect for this task. The UAVs would have a payload of camera equipment and communication equipment to broadcast (encrypted, of course) its feed. It would use solar panels to run during the day, and at night, it would turn off the camera and run on battery power so that it wouldn’t have to use energy on landing and takeoff every day.

The camera spec

The primary use case is tracking highway traffic. We can assume cars may be moving at up to 80 mph (36 m/s). Using a Honda Accord as an example car, that means that the car travels 7.5 car lengths per second (the Accord is 4.8 meters long). For the images of cars to not be blurry then the frame rate must be much faster than 7.5 fps (or at least the exposure time must be much less than 130 milliseconds). It’s not uncommon for modern digital cameras to be able to capture 60 fps at 1080p. Unfortunately, that won’t be high enough resolution, as each pixel would cover several cars. Sacrificing frame rate, it’s possible to get 6fps and an exposure time much less than 130 milliseconds with the Sony Alpha SLT-A99.

The UAVs would fly at an altitude between 3,000 and 10,000 meters, which is high enough to capture large chucks of the city. The amount of area covered by each UAV won’t be limited by the altitude, but instead by the resolution of images recorded. Each car on the road should be covered by several pixels. A reasonable scale is each pixel is a meter by a meter. That would make cars around 5 pixels long. The sensor of the SLT-A99 is 6000 x 3376 pixels, so it could cover 20 square kilometers. With that amount of coverage, it would only take 65 UAVs to cover all of Los Angeles, which is not a particularly small city. With a little engineering effort, one could combine several of the image sensors onto a single UAV and cut the number of UAVs needed to patrol the skies.

What to do with the data

With detailed data about the routes of every car and their reaction to their surroundings, it should be possible to make very accurate models of driver behavior. These models could easily be validated against new days of traffic. These models could help answer what changes to road design and construction could reduce traffic accidents and jams. It could also give insights into what makes for good defensive driving and traffic reducing driving. What if you could alert drivers that there would be a jam ahead and convince them that they should slow down by 10 mph? Would that help or hinder? There are many interesting questions that could be answered with these data.

Getting dangerous drivers off the road

The data from the UAVs could find the most aggressive drivers and send police cars to pull them over or combine the UAV data with highway camera images and just mail the offender a ticket.

Cirrus Traffic - The motivation

One of the biggest drains on the quality of life of suburbanites is traffic. It’ something we have to deal with everyday, but we really don’t understand it very well. We know when accidents happen, but we don’t necessarily know how many close calls there are or the exact confluence of factors that caused a particular crash. While traffic has become more important, UAVs have gotten cheaper and easier to use.

Cold Vault - The pitch

Tame the biggest energy hog in your house--the fridge, with Cold Vault. Your fridge will sip energy instead of gulp it.

Cold Vault - The fun part

There is a lot of challenging mechanical engineering required for this project. The refrigerator needs to be designed to last for twenty years. Not only making the fridge work, but making it work for two decades would require serious engineering skills.

Cold Vault - The growth potential

If one hundredth of the households in the country bought one every year, that would be 1 million units sold or $4 billion in revenue per year.

Cold Vault - The monetization

This fridge would probably have an annual energy consumption of one twentieth modern refrigerators. Modern fridges consume around 450 kWh per year. In LA where it costs around $0.22 per kWh, that comes out to be $100 per year. With older fridges it’s more like $300/year. Replacing an old fridge with one that costs $5 a year to run would save anywhere from $95 to $295 a year. I think the fridge could sell for $2,000 to $4,000. Even without the cool factor, the fridge would pay for itself in as short as 13 years.

Cold Vault - The idea

The there are two big reasons why fridges consume large amounts of energy. First, there is idle energy consumption used to keep the contents of the fridge and freezer cool. Heat gets into the fridge because it doesn’t have perfect thermal insulation. Heat gets in from all directions to varying degrees, but the biggest culprit is the seal around the door. The second main source is from opening the door and letting the warm room air mix with the cold fridge air. The door doesn’t have to be open for long to lose a lot of the of air that the fridge worked so hard to cool. It’s even worse with freezers (non-drawer style). If you watch from the side, you sometimes see the cold air pour out of the fridge (which you can see because it condenses the water in the air in the room).

The solution to these problems it to minimize the energy exchange between the fridge and the room. The way to do that is to rethink the way one interacts with a fridge. Normally, we open the door and look around for what we need and moves things, if necessary. This new fridge would have cameras on the inside and would take pictures from several angles of each item to produce a 3D reconstruction of the item. When the consumer wants something from the fridge, she would tap the screen on the front of the fridge and see a summary of the contents of the fridge. If something looked appealing, she would tap the image of the item and it would be moved to the exchange point. You can think of the exchange point as a box within the fridge, the front of the box is flush the front of the fridge and opens to let the consumer put things in and take things out. The back of the box can also open and close as part of the exchange. The front and back are never open at the same time which greatly minimizes the cold air loss.

The biggest engineering challenge is to maneuver the items around in the fridge to pack them efficiently. There are at least two ways to accomplish this task. First, a conveyor belt system could move things around. To have multiple levels (which would be important) the fridge would need a section of at least one of the level to be able to move up and down, which isn’t too crazy. The other way to solve this problem is to put each item on a tile and have the tiles shuffled around the fridge either using simple robotic arms to pick up the tiles or by moving the tiles via magnets (and an elevator to get between levels). There would be a magnet in every tile and electromatics under each level to move the tiles around. Other than the exchange point and the computer-organized contents of the fridge, everything else would be the same. Specifically, the cooling system would stay the same and the overall form factor would stay the same.