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BrakingPushRatio is too small to stop the car

asked 2022-06-17 10:38:21 -0600

rivership57
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Hello Hatem, I am using autoware with openplanner.

It seems that, the car will not get enough deceleration while approaching its goal position and finally go over the goal position.

I think this phenomenon maybe related to the value of BrakingPushRatio is too small. I found the code where using BrakingPushRatio to calculate deceleration, here is a screen shot of this piece of code. https://drive.google.com/file/d/1B5Ev...

In my trial, if I set BrakingPushRatio to 1, the ego car will go over the goal position and collide with an obstacle. Video: https://youtu.be/3LnlDjvNiAM

And if I set BrakingPushRatio to 10, the ego car will stop before the goal postion. Video: https://youtu.be/cYT5JJz3k9c

I'm wondering if the phenomenon (the car goes over the goal position) is actually related to value of BrakingPushRatio, or there are some other root causes?

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answered 2022-06-17 10:57:32 -0600

Hatem
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I think the main problem is the feedback velocity from the simulator.

if the velocity feedback is correct and the topic frequency is 10 hz or more , this should work fine.

increase deceleration to -5 m/s2 and BrakingPushRatio to 20. so you can find how early the vehicle will stop.

This distance should be consistent any time you run the simulation with any max velocity value.

You can control this distance using two parameters: distance-to-goal , additional-braking-distance.

Once you fixed that, you start decrease the deceleration and braking-push-ratio to achieve smooth braking.

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Thanks for your advice! It works fine with updated parameters now.

rivership57 ( 2022-06-18 21:33:18 -0600 )edit

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Asked: 2022-06-17 10:38:21 -0600

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Last updated: Jun 17 '22

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