調査テーマ
前回の調査では、驚きの通信可能距離69m(理論値超え)を計測し、様々な施策への利用が期待できる結果となりました。
この通信可能距離で、例えば、車にBeacon端末を付けて街を走ることで、道行く人々へ通知することも可能なはずです。
ここまで考えてふと疑問が浮かびました。
「移動するものに端末を付けたとしてスピードの有無は関係あるのだろうか?時速何kmまでいけるのだろう?」
これも事実を明らかにする必要がありそうです。
From our last investigation, we've measured a surprising potential transmission distance of 69 m (which exceeded theoretical value), a result that we hope can have application to various policies. This potential transmission distance can, for example, can be used in a car beacon and be used to send notifications to people walking down a street.
Now that we think about it, a question has come to mind.
"Will speed be a factor when we put this instrument in a moving object? Between which kilometers per hour will this work?"
We will probably have to figure that out.
In the previous investigation, we marked a surprising transmissible distance of 69m (beyond theoretical value), which might be possible to apply for several policies.
With this transmissible distance, for example, a car driving on a street with Beacon terminal might enable the notification to passengers-by.
So, a question came up to my mind.
If we equip the terminal to moving thing, does it matter if they are speeding or not? How many km/h will be available maximum?
We need to find the result of this issue.
During the previous operation test, the communication range of iBeacon was proved to be amazing distance of up to 69 m (exceeded the theoretical range), and it offered the expectation to various applications.
For example with this communication range, it may be capable of notify to walking people by installing a iBeacon terminal to a car.
When I have been thinking about this, there has come up one doubt.
"If iBeacon is installed to the mobile object, is there any relation with the velocity?" "Up to what velocity will it be possible?"
This doubt also needs to be clarified.
今回の調査は iBeaconが時速何kmまで認識できるかという実験をおこないます。
調査概要
2台の車を用意し、一方にビーコン端末を装着。
もう一方にデモアプリをアクティブにした受信端末を用意。
お互いの車をすれ違いさせ、時速何キロまでiPhoneが認識出来るかを測定します。
いわゆる相対速度を用いた実験です。
今回は電波強度:強で設定しました。
Summary of Investigation
Prepare two cars, one of them Beacon terminal equipped
Another car equips the reception terminal with demo-app active
Each cars passing by, then measure how many km/h can iPhone recognize
An experiment with so-called relative velocity
This time we set the parameter of radio wave intensity: strong.
Summary of operation test
Provide two cars, and install iBeacon to one car, and carry receiving terminal with active demo application in the other car.
Run two cars in opposite directions, and test up to what speed does the receiving terminal recognize the iBeacon installed in the oncoming car. It is the operation test with relative speed.
The operation test at this time was conducted while the transmission strength was set to the strong.
Survey summary
Prepare two vehicles, one of them is with a beacon installed.
A demo application that is activated to receive signal is installed in the other vehicle.
Measure the max speed that IPhone can be able to recognize , when the two vehicles passing by each other.
It is the experiment by using relative speed.
The signal intensity:strong
調査開始
休日の昼下がり。快晴。
予め下調べしておいた交通量の少ない道路近くに集合しました。
ビーコン端末を丁寧に車に装着します。
運転席の内側に丁寧に装着。
これで何が起きてもビーコン端末の脱落などはあり得ません。
受信感度に影響を与える可能性があるので、窓は問答無用で全開です。
もう一台に受信担当メンバーが乗り込みます。
これで準備万端。実験の成功間違いなし!
さっそくビーコン端末装着車が反対車線へ移動。
お互いに一定の速度ですれ違う際の相対速度による実験を試みます。
It's afternoon during the weekend and clear.
We've assembled at a road where we have previously confirmed has little traffic.
We've carefully installed the beacon onto the car.
We've installed it right beside the driver's seat in the inside part. If anything happens, the beacon will not fall out of the car. We also opened the windows fully in order to increase the likelihood of successful transmission.
We've also put in someone who will be taking in the reception in another car.
Now everything's ready and and we should be successful with our experiment!
We drove the car with the beacon on the opposite lane.
Both cars are driven at a set speed and we are basing this experiment on the relative velocity of the cars as they pass each other.
In the afternoon of a holiday.
We gathered near a road we previously research with low traffic.
Install the iBeacon to a car with great care.
The iBeacon was installed inside of the car at drivers seat side.
Therefore, it is not dropped off from the car even something is happened.
Because it may affect the receiver sensitivity, the window is opened without any question.
Person in charge of receiving terminal rides to the other car.
This is all set for the operation test. The operation test will definitely successful.
The car installed with the iBeacon is moved to the opposite lane immediately.
Try to conduct the operation test by passing two cars at steady speed each other.
まずは時速60キロで実験開始。
相対速度で言えば時速120キロです。
これで受信ができれば高速道路での利用も視野に入ります。
時速60キロをキープ。対向車線にビーコン端末装着車が迫ります。
さて、結果は?
反応がない。相対速度時速120キロだとさすがに反応しないようです。残念。
気を取り直して時速50キロでも試しましょう。
受信できてないですね。
続けて時速40キロも試します。
時速40キロもダメですね。
速度と共にテンションも下がっていきます
時速30キロもダメでした。
The relative velocity will be 120 km/h.
If we are able to get a reception, then this can also have application on freeways.
We've kept it at 60 km/h. The car with the beacon came to us on the opposite lane.
So, what is the result?
No response. With the relative velocity being 120 km/h, of course there would be no response, which is a shame.
We regrouped and tried again this time going at 50 km/h. But we didn't get any reception.
We then tried it at 40 km/h, but even that didn't produce any results.
Our excitement steadily dropped with the speed.
Even an attempt at 30 km/h was a bust.
In relative velocity it will be 120 km/h.
If the reception were possible, the usage could apply for highway driving.
Keeping 60 km/h, the Beacon terminal-equipped car is approaching from the opposite lane.
The result was: no reactions. I'm afraid the relative velocity of 120 km/h doesn't work.
Let's go on to further experimentation: how about 50 km/h? No reception.
How about 40 km/h? No reception.
The less velocity the less our hope.
30 km/h didn't work, too.
The relative speed becomes 120 KPH.
If it is successive, the operation test at expressway is brought to be perspective.
The receiving terminal does not react. It does not react to the iBeacon signal at the relative speed of 120 KPH as expected. What a pity!
Pulling ourselves, and try at the speed of 50 KPH.
Cannot receive the iBeacon signal.
Out tension goes down as the speed goes down.
No at all at 40 KPH.
Not yet at 30 KPH.
相対時速60キロでの受信が不可能だと分かりましたので、高速道路で走行中の利用は難しそうですね。
とはいえ、まだ一般道での利用は可能な速度域です。
これ以上速度が下がると、さすがに他の車の通行に影響が出ます。
そこで受信担当者が車を降り、ビーコン端末装着車を待ち受けることにしました。
電波状態を考慮して、遮蔽物の少ない橋の上で待機。
ビーコン端末を助手席側に取り付け直し、いざ時速50キロで走行。
はい、ちょっと覚悟してましたが、やっぱりダメでした。引き続き時速40キロで挑戦です。
However, there is a chance that it could work at speeds that are set at local streets. If we decrease the speed even more, the influence of passing vehicles will indeed increase. So we decided to take the person in charge of the reception out of his vehicle and have him wait outside for the car with the beacon.
Taking electric magnetic waves into consideration, we've decided to have him wait on a bridge where there are relatively few obstructions.
We put the beacon on the passenger side seat, and drove the car at 50 km/h.
Well, we did kind of prepare for the worst, but indeed it did not work. Next we tried it at 40 km/h.
However, this velocity still applies for local streets.
If the velocity will be lower, it probably disturb the traffic of cars.
So the reception staff got off the car, waiting for Beacon terminal-equipped car.
The staff was waiting on the bridge with no barriers.
Beacon terminal was re-equipped in passenger seat's side, driving a car with 50 km/h.
We had no expectation, no, it didn't come true. We'll go on further to 40 km/h.
Though it is still within the speed range on the public road.
The further reduction of speed may cause adverse effect to the other running cars.
Therefore, we decided that the person with receiving terminal gets off from the car and wait for the car installed with iBeacon on the sidewalk.
We chose the waiting point on a bridge with consideration of signal reception obstruction.
We change the installation position of the iBeacon to the assistant driver's seat and drive the car at 50 KPH.
Well, it is failed again though we make up our mind to be. Challenge at the speed of 40 KPH again.
時速40キロも受信ならず。
そもそも移動しているとダメなのかも?
念のため、時速30キロでも挑戦です。
期待はしていませんが。
もはや無理なのでは?という空気の流れる中での実験です。
おおっ!片方が受信しました!
時速30キロで初めての受信成功。
なぜ片方だけが受信できたのか?受信端末依存などもあるのでしょうか
若干の謎は残しつつも、成功したことは大きな収穫です。
この速度域以下の使用で考えるなら、例えば宣伝トラックなどゆっくり走る車や、原動機付自転車などから発信ができるのではないでしょうか
Or no reception impossible at all when moving?
Finally, we tried 30 km/h, which we didn't expect any good news.
Wow, one receiver did receive!
The first success in 30 km/h!
Why the one terminal received, depending on reception terminals?
We've got some issues to be clarified, but this success is really surprising and amazing.
If we consider the usage below this velocity, a slow-driving cars, for example advertising trucks, motorized bicycle, etc. may send the signal.
It is assumed that this function can not work during moving.
As a precaution, a test at 30 km/h is also conducted without too much expectations.
Nobody smell the success of this test.
However, one of them worked !
It is the first time to success in receiving singal at km/h.
The reason for why only one received signal may be depending on the reciving device.
Anyway, it is a big harvest, although some mysteries remains.
It is possible to use this application on the vehicle with low speed such like advertising track,or motorbike.
これ以下の速度は道路交通の妨げになる恐れがあるため、今回はここまでとします。
調査結果
「アイビーコンは時速30キロで受信が可能(たぶん)」という結果をもって、今回の調査結果としたいと思います。
Search result:
I conclude the report with the summary that "iBeacon can possibly be detectable at the velocity of 30 kmh or more".