Home Assistant missing readings from ESPHome

ESPHome
1

I have an ultrasonic sensor in ESPHome that updates every second, with a few filters in place. There are times when it updates immediately in HA, and other times where it doesn’t for 15-20 minutes. Currently I’m looking at values tick by in the ESPHome web portal, but I am not seeing an update to the sensor in HA.

Here’s my sensor config in ESPHome

  - platform: ultrasonic
    trigger_pin: GPIO 5
    echo_pin: GPIO 18
    name: "Car_position"
    update_interval: 1s
    pulse_time: 10us
    timeout: 15m
    filters:
      - filter_out: nan
      - sliding_window_moving_average:
          window_size: 5 #creates a moving average of the last 3 values
          send_every: 1 #sends the moving average at every measurement (but only if it passes the delta filter below)) 
          send_first_at: 1 #after startup immediately start sending the result rather than wait for the first 10 measurements
      - delta : 0.7

I believe it should send a reading every second, unless that specific reading is 0.7 different from the moving average of the prior 3 readings. Currently the reading is stable, so I should be seeing regular updates. I understand HA will ignore it when the current and prior reading is the same. But in this case, the sensor is reporting 2.07 (+/- 0.1) repeatedly and the sensor in HA is showing 1.5 or so.

I don’t see any issues in the HA logs.

Anything else I’m missing that could. cause HA to drop readings?

I do wonder if I’m misunderstanding how the sliding window average is working with the delta. I assume if I have a reading get discarded by the delta, it still gets incorporated into the new moving average. But if it doesn’t, obviously I could get stuck at a reading.

2

The filters are applied in sequence. Means: NaN values are filtered out, a sliding average is calculated and only if the delta of it is more than 0.7 the value is published.

3

Hah, I started a response and now I see an obvious flaw. Rubber ducking for the win.

I realize in the example I provided, it wouldn’t work. If the value was 1.5, and it changed to 2.07 that’s a delta of 0.57. After three readings, the new moving average would be 2.07 which is within the 0.7 delta and would never get reported.

I have been tweaking these settings, and at some point I think I changed my ranges for ‘garage open’ to a point where this delta is a problem. I’m not sure how it’s been working at all actually.

I think root cause is that the sensor is showing a larger distance than it should for ‘garage open’ state now (1.5 is too much). But I think the answer is that I should change my delta.

Still learning how to best troubleshoot this stuff. For instance, I don’t have a way of knowing which readings are making it through the filter, other than by looking at HA.

Thanks for the help!

4

Maybe you can work with a negative offset if the distance is always the same value wrong or calibrate with calibrate_linear

5

Unfortunately in this case they are randomly incorrect values. I’m not sure why they exist, but they are infrequent enough that I’m able to smooth them over with those filters.