We want to improve Toronto Streetview. Google cars will drive in Toronto and take pictures. How long it will take?

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We want to improve Toronto Streetview. Google cars will drive in Toronto and take pictures. How long it will take?

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Payman Salimi · Answer 1 · 2020-05-11T03:59:07+0000

- Do you mean the City of Toronto or GTA (Great Toronto Areal)?

- You mentioned Google Cars, How many cars are Moving in town?

- I assume while the vehicle is driving taking the 360 pictures and there is no need to stop?

- Do you want to calculate the total time in hours? or Day? As Google Car only works while it is not dark?

----

Here are My Assumptions:

1. There is on Google Car Taking Picture

2. I don't consider Stops signs, Red Lights and Traffics

3. While the Google Car is driving, take a picture without any need to stop.

4. We are calculating the time it takes for the City of Toronto and not GTA

-----

Here is my Equation: Total Time in Hour =( Number of Streets in Toronto * Average Lenght of each Street ) / Average Google Car's Speed

Number of Streets In Toronto:

Toronto is one of the Biggest Cities in Toronto, which has almost the shape of a Rectangle where its width is four times its length. We assume In the Middle of this rectangle, which includes Yonge street (the straight street from Lakeshore to North of Toronto) has 200 blocks. And in each block, there are 2x2 streets, which turn to 800 Streets. As a result, with a length four times the width, we have around 3200 streets in Toronto.

Average Lenght of each Street:

Toronto has long streets like Yonge with is over 50 KM (but 20 KM of it is in Toronto) but there are many parallel streets with Yonge with goes from south to north and same on the east to west, however on the north side which is more residential there is a much smaller alley with even 0.2 km. I take an average of 2KM per street length.

Google Car Speed:

In Toronto, average speed in main streets is 50 KM, and in residential areas are 20 KM where there are schools. I assume based on some red lights on each intersection and stop sights in streets, Google Car's average speed won't exceed 20KM.

As a result; the Total Time in Hour = 3200 KM * 2 KM / 20 KM/Hour = 320 Hours (This is total time)

Wendy Xue · Answer 2 · 2020-05-04T17:34:52+0000

First I'd like to clarify my understanding of how Google maps the street view.

- Google drivers will drive the car with a high speed camera that takes photos continuously as the car passes through the street, so there won't be any time required to stop to take photos

- Google do not take photos for back alleys that are not accessible to cars

- Do we need to include times that a Google car needs to stop at traffic lights or stop sign? I'm assuming we are primarily interested in the time used to take photos and will exclude these unpredictable wait times

Calculation:

Total # of times to map Toronto = # of streets in Toronto * Avg length of street * Avg time needed per street

1. # of streets:

- San Mateo California has about 50 blocks from downtown to south border. Assume the city is about the same size width wise, the total number of streets in San Mateo is about 50 * 2 * 2 = 200

- Toronto is the largest city in Canada and is pretty spread out. I can safely assume it's about 20 times larger than San Mater in terms of sqaure footage. # of street in Toronto = 200 * 20 = 4000

2. Avg length of street

- very long streets such as Young street is more than 20km. Majority of the streets in residential areas are shorter, may be 2km. Average street length is 3km

3. Avg speed of Google car

- Street speed limit is about 30 km/hour in residential area and 60km/hour on major road Assume the camera is high speed and continuously shooting. Google car doesnt have to be super slow but may want to drive at a slower than speed limit to be consistent and avoid children in residential area. Let's say it drives in range of 5 km/hour in busy downtown area, and at speed limit on major road around 60km/hour. Avg speed would be around 20km/hour, as majority of the streets are in residential area

Going back to the equation

# of hours needed = 4000 street * 3km/street * 20km/hour = 12,000*20 = 240,000 hours

ds9 · Answer 3 · 2020-04-30T06:18:56+0000

Assumptions:

1. By streets, I mean roads that lead to residential properties, commercial locations etc. I will not include roads that are inaccessible to cars.

2. Toronto is the most populated Canadian city.

3. Assuming it to be much smaller than LA/NY but similar to Chicago or little smaller than Chicago.

4. Time will be calculated in days

5. Assuming there is only one car that drives all of Toronto

Calculation:

Time taken = Total streets * Time taken per street. (A)

Calculating (A) for 3 different types of streets.

3 different types of streets are Highly populated, medium populated, sparsely populated.

Highly populated means many restaurants, offices, buildings, residence. This would be around 30% of the Toronto streets

Medium populated are few building, homes, maybe a restaurant or small shopping mall. This would be around 50%

And, sparsely populated just residential areas, hilly areas around 20%

Total Streets:

I believe LA has around 30000 streets, Chicago around 10000 streets and Toronto would be around 10000 streets

Time taken by street types

For highly populated street, a car could take pics for 10 streets a day

For medium populated street, a car could take pics for 20 streets a day

For sparsely populated street, a car could take pics for 40 streets a day

So calculating equation A for highly populated streets:

10,000 * .3 * .1 = 300 days

So calculating equation A for medium populated streets:

10,000 * .5 * .05 = 250 days

So calculating equation A for sparsely populated streets:

10,000 * .2 * .025 = 50 days

So total of 300+250+50 = 600 days