With AVC fast approaching, we have redesigned the course to accommodate the addition of the Power Racing Series and the return of Combat Bots. With that revision, we opted to completely line the classic ground race course with bales of hay.
For those concerned about how the bales will interact with the remote sensors commonly used on autonomous vehicles, worry not. We’ve done a bit of testing ourselves using the two most prevalent technologies in remote sensing: ultrasound and infrared.
These are the four sensors we tested:
- Ultrasonic Range Finder - HRLV-MaxSonar-EZ4 (SEN-11309)
- Ultrasonic Range Finder - HRXL-MaxSonar-WR (SEN-11724)
- SparkFun ToF Range Finder Sensor - VL6180 (SEN-12785)
- Infrared Proximity Sensor Long Range - Sharp GP2F0A02YK0F (SEN-08958)
You can find the wishlist below, and the example code here.
For the test, these four sensors were wired to a SparkFun RedBoard. The sensors were then aimed at a sample hay bale to determine if each could detect it. The test platform was then moved toward and away from the hay to determine if the values changed. In addition to the indoor testing shown in the video, we also did some outdoor testing in sunlight.
I was concerned with the hay bale surface obscuring ultrasonic signals, and with the sunlight washing out the infrared signals. The results of both tests were encouraging, as neither problem occurred. All four sensors returned meaningful data, which changed with the distance.
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Take me there!
Sorry for the delay folks.
I ran an oblique case with approximately a 30-degree angle of attack.
Each sensor indicated a significant change in readings except the Sharp IR, which indicated a very slight change. The serial data was captured and saved to a .txt and added to the GitHub Repo
I hope this helps.
Why is the video marked as unlisted?
I only saw you doing tests at 90 degrees. Did you do any tests at oblique angles? How well do the tests perform at oblique angles compared to an interior wall? In many cases, the sensors are not going to have that perfect 90 degree angle on the hay bales, so knowing what the valid range (as in the valid angle) for the sensor is is very important. Otherwise, you might as well just use bump sensors and GPS waypoints.
We have not done any tests at obliques. We can build up a test case for various angles of attack and report back to you, as our duties permit (may take a few days to get to).
I added a brief summary of the oblique test above
I know that you were talking about using plastic barriers for PRS course, is this still true?
Also, any chance that you can publish the raw data for the tests that you did?
It looks like we will be using hay bales for both PRS and AVC.
Unfortunately, the data was just streaming serially and not captured, so there isn't a log file for the test as seen on the video.
Ok, well I can still read the numbers off the video feed. Also, I second the request for oblique angles. Anyway, thanks for doing this test, it should be super helpful; you guys are awesome!
I added a summary of the oblique test results. I included a capture of the stream so you can see the data this time.