topic Re: AGV COLLISION in FlexSim Forum

AGV COLLISION

a9080109 — Thu, 30 Jun 2022 06:13:56 GMT

[ FlexSim 20.0.10 ]

碰撞偵測.fsm現在關於COLLISION的部分已經趨於完美但我現在有一個想法就是在碰撞的過程中我可以控制其中一台車先移動嗎?

現在是兩台車停下來去做等待那左右兩台車必須停留，那我現在想要左邊停下來5秒鐘後回復運行，右邊則直接進行工作，這是可以完成的嗎?

Re: AGV COLLISION

moehlmann_fe — Thu, 30 Jun 2022 08:01:08 GMT

Here is my attempt to implement this:

I added a custom code activity 'Compare position in network'. In this activity I read the current position of the AGVs on their path from the navigator's tree.

In order to make this work in most situations and because 'left' and 'right' aren't useful indicators because the direction depends on the viewpoint, I implemented the following logic:

If both AGVs are on the same path, the one that has a higher position can continue immediately. (Each path has a set direction, even if it allows two way travel. 'Higher position' means the AGV is position farther along in that direction)

If they are on different paths, the AGV whose path has the higher rank in the tree can continue immediately.

This is done by setting the 'priority' label on the token. The delayTime is later multiplied by this value, so if it is 0, the AGV can continue immediately, if it is 1, the delay time happens as before.

mz.fsm

Re: AGV COLLISION

a9080109 — Thu, 30 Jun 2022 08:43:47 GMT

我如果想要套用到別的模板中我該怎麼做直接複製pf是一個好的方法嗎?

Re: AGV COLLISION

a9080109 — Thu, 30 Jun 2022 08:45:28 GMT

還有關於樹中的設定可以請您提供您的方法給我嗎?

Re: AGV COLLISION

moehlmann_fe — Thu, 30 Jun 2022 09:03:00 GMT

If the other model uses the same process flow, then yes, you should be able to simply copy the new activity and the changes to the delay time assignment.

The token has a reference to the AGV. From its variables treenode, I get to the node of the AGV inside the navigators tree.

The navigator stores the following information:

- The distance the AGV has already traveled during its current movement. ('cachedTravelDist')

- The current travel path of the AGV. This path is split into sections by control points and transfers between paths.

- Each section contains information about the start position of the travel on that section (fromDist) and the end position (toDist). Both are given as distance along that path object.

- Each section also knows how far into the total travel distance the AGV will arrive at it (atTravelDist).

In this screenshot we see that the travel starts 0.1m along Path1. The AGV will then travel to the end of Path1 at 6.22m with a control point at 4.69m inbetween. So after a total travel distance of 6.12m it will transfer to Path8 at travel another 6.02m on it (from 0 to 6.02).

Together with the total travel distance from the picture above, this allows us to determine which section the AGV is currently on (by comparing the 'cachedTravelDist' to the 'atTravelDist' values. Once we know the section, we can calculate the current position on that path.

Re: AGV COLLISION

jason_lightfoot_adsk — Thu, 30 Jun 2022 11:32:40 GMT

You could also use:

agvNavNode=AGV(token.otherAGV);

Re: AGV COLLISION

moehlmann_fe — Thu, 30 Jun 2022 12:50:14 GMT

True, thanks for the hint.

Re: AGV COLLISION

a9080109 — Mon, 04 Jul 2022 02:45:24 GMT

@Jason Lightfoot

如果是您的話你會怎麼設計這個模型

@Felix Möhlmann

我好像沒有辦法完成複製的工作是我的樹沒有設定好嗎?如果是的話請告所我怎麼設定以及token 'priority' 在那裡做設定?，還有我沒有辦法在模型中利用sorce生產token(a connect沒辦法使用)還有我想請問如果我的邏輯是以紅色為下貨點，往紅色方向靠近的可以在碰撞中優先行動那我在邏輯中該如何更動

觀察表格可以碰撞並沒有完整的模擬，三台車應該會發現碰撞te126 12 16 26三種情況但模型沒有完整的模擬，想請問是哪裡不夠完善。

0421-1-jl4 (1).fsm

Re: AGV COLLISION

moehlmann_fe — Mon, 04 Jul 2022 08:43:41 GMT

The model wasn't successfully uploaded, so I can't look at it to see what's wrong. The only changes compared to the model you uploaded in the question are the 'Compare position on network' custom code activity and the addition of the priority factors in the delay time calculation.

To have the AGVs travelling towards the red queue have priority, all paths have to be drawn away from it (and then switched to two-way) with the current settings.

Alternatively if all paths are drawn towards it, you can simply switch the priority assignment in the 'Compare position on network' activity.

Re: AGV COLLISION

a9080109 — Mon, 04 Jul 2022 18:25:41 GMT

0421-1-jl4 (1).fsm@Felix Möhlmann

我想我已經解決ˊ了但我還是有幾點不了解，

為啥切換優先度就可以解決這個問題，我想我對於code還是有不了解的的地方。以及token.priority是在code裡create的嗎?還是在其他地放賦予token的另外如果我現在要完成這樣行走的碰撞，我可以如何去實現?

Re: AGV COLLISION

moehlmann_fe — Tue, 05 Jul 2022 06:16:36 GMT

Each path has a direction (even if set to two way). It is determined by which end has an internal coordinate of 0. The position of the AGVs is measured as the distance how far along the path they are. The navigator stores the starting point of travel on that path (fromDist) and the end point (toDist). These values together with the current 'cachedTravelDist' can be used to determine the AGV position in terms of path coordinates. Due to the set direction of the path, this is independent of their travel direction!

The current code then assigns them the priority labels based on which AGV is farther along. Later, the delay time is multiplied by this value, so priority = 0 means the AGV can continue without delay.

This label does not exist on the token prior to the custom code activity. Assigning a value to a label that does not exist will automatically create that label. 'token.priority = 0 / 1' does this.

If you switch the direction of the path, the distance along is measured in the new direction, which then also switches what AGV will be able to continue. This is the same as if you changed the label assignment to prioritise the AGV less far along the path.

(Switching path direction and label assignment has the same effect)

Again, this logic doesn't change anything about the way the collisions were handled before. You can continue either AGV at any by 'resuming' it (which normally happens after the delay time).

Re: AGV COLLISION

a9080109 — Tue, 05 Jul 2022 12:58:59 GMT

0421-1-jl4-1.fsm@Felix Möhlmann 那我上面的模型怎麼會無法順利運作，還有樹的部分是怎麼打開這些資訊的

我想用這個方向來進行模型以及最後一個問題˙是我無法在這個模型新增sorce以及a連結。

Re: AGV COLLISION

moehlmann_fe — Tue, 05 Jul 2022 14:54:21 GMT

I don't know what you mean by 'work correctly'. When I run the model I get an error that no path to ControlPoint5 can be found. Reattaching the curved paths at the intersection fixed that for me.

'getsdtvalue()' can be used to read data from nodes like that.

I'm also not sure what you mean by "adding a source or link". Connections currently aren't shown in the model because the option is not checked, but everything works normally for me.

0421-1-jl4-2.fsm

Re: AGV COLLISION

a9080109 — Tue, 05 Jul 2022 15:13:57 GMT

我嘗試添加了一個source 並想利用a連結來完成連結但我不能使用a連結

Re: AGV COLLISION

moehlmann_fe — Tue, 05 Jul 2022 15:24:10 GMT

As I said, everything works for me and I can add a source and connect it with no problems.

0421-1-jl4-3.fsm

I don't know what the issue on your end could be.

Re: AGV COLLISION

a9080109 — Tue, 05 Jul 2022 15:29:58 GMT

我在其他的檔案中可以正常使用所以我也不知道怎麼會這樣發生。

Re: AGV COLLISION

a9080109 — Tue, 05 Jul 2022 15:39:09 GMT

test.mp4

Re: AGV COLLISION

moehlmann_fe — Tue, 05 Jul 2022 15:46:08 GMT

The connections are there. As I mentioned above, activate the 'Show Connections' option in the properties of the 3d view and they will appear. (Click on an empty spot in the 3d view to show the properties on the right side of the screen.

Re: AGV COLLISION

a9080109 — Thu, 07 Jul 2022 06:11:51 GMT

不好意思已經解決了，現在我試題者取有關代碼的部分可不可以理解請你說明一下定義的問題以及參數。

Re: AGV COLLISION

moehlmann_fe — Thu, 07 Jul 2022 07:32:39 GMT

I added more comments to explain what each code line is doing.

0421-1-jl4-fm4.fsm