Electron Project Discussion [Hardware]


#61

Here is the last code I tested which was firmware 0.6.0

https://go.particle.io/shared_apps/5880d2fc82248db40b000a58

Usually, I would not sleep the fuel gauge because it caused wide swings in battery SOC on wake up but you can test that also if you want.

You may want to try the 0.7.4 firmware since I think the Cellular command is no longer needed to get it to turn off completely.


#62

Thanks, so that code for some reason doesn’t seem to work on my 0.6.2 Electron, although I directly copied and pasted it…strange, but Cellular.off(); does work and hopefully will achieve the same thing…let’s wait and see :stuck_out_tongue:

I will consider upgrading to 0.7.0-rc4 the next time I have to get those devices off the containers (trust me, it’s not fun doing that :joy: )


#63

Cool! Looking forward to seeing what happens with the SOC.

Do you have a picture of what your setup looks like installed?


#64

Took some individual components and put them together to give an impression. Don’t have any VL53L0X available right now, but I glued them to the hole on the lid with heavy-duty tape, and wires leading back to the PCB. All my actual sensors are outside at the moment :smiley:

For the enclosure, Polycase designs really nice ones at an affordable price. Sensor goes on a separate metal bracket, as I found when it gets mounted directly onto a container, the vibrations when the top is opened/closed by people really messes with the accelerometer.


#65

A couple of them came online and received the update. As soon as they receive it, they immediately reboot so I receive their SoC before and after the update, which should equal the energy it requires to do one wake-up of the device. Across all devices this seemed to be 0.16% with a 2A LiPo. Going with that, there is absolutely no way 3-4 Wake ups on a day can lead to an 11% drop and it’s a confirmation that I did things wrong with Deep Sleep. Now will wait until tonight when they report in again, where I can verify if the SoC-drop is significantly reduced or not after 6 hours of Deep Sleep.


#66

Cool, yes I have used Polycase cases in the past also and they are priced good and the quality and look is good also.

I looked at the case your using on their website also but was wondering how to get the sensor pointed down at an angle like you did with the metal bracket.

I was thinking about the best way to get 3 distance sensors pointed down from the back wall of the can to get a better overall idea of what the trash levels are vs. just having one sensor. Maybe 1 sensor is enough though.


#67

Look at these guys: https://www.emachineshop.com/
You can have a low-quantity metal bracket made to suit your own requirements.

Personally, I had them made at a nearby workshop for 10 bucks a piece. The one in the picture is an old one, the newer ones have an angle that is based on the container size, so that it looks slightly beyond the center-point when it is mounted on the side.

I would say 1 sensor is not sufficient to very accurately measure, as from my own experiences often thrash is located in one part of the container and not the other, either greatly over- or underestimating the fill rates. Even with 3 of them you still can only look at the waste from one angle, and large objects that fully block the sensor may still be there

I’d say with a VL53L0X and a typical 6-8yd container, you’re probably gonna get 75% decent results and 25% that are all over the place.


#68

Yea, let them stabilize and see how the SOC readings come out.

Glad the units received the updates without a problem upon waking up. How are you going about triggering the Electron update process when they wake up? Do you have these units in a product group on the Particle console so they automatically update when they wake up?

Also, are you using a dashboard to visualize the trash level status of each can?


#69

Yeah, I assigned them to a product group, and for now at each wake-up they will sit idle for half a minute to download any pending updates. Later on I will only enable that feature 1 day/week.

At the moment I’m using Thingspeak to get everything in an Excel sheet. I don’t need fancy graphs yet, just something that let’s me read their values.


#70

Yea the camera makes a lot of sense although it does increase complexity and cost of the solution via hardware and data usage.


#71

I think I’ll get started on the Camera sometime next week, I’m just wrapping things up now with the battery-issue and some of the components i.e. PCB, Antenna. The antenna is a bit of a worry for me because with how much the container is being shaken around when picked up by a truck, I can see this thing eventually dislodging.The u.fl connector is pretty fragile to movements but the Particle Taoglas doesn’t actually fit properly in my case so I can apply adhesive to it


#72

Had 3 devices come in this evening (others downloaded firmware when they did - so it’s too early to say for them). All 3 reported only a 0.20% drop after 6 hours. By reducing wake-ups to once every 24 hours, I can probably can get 4-5 months out of the 2A LiPo again, and several years hopefully with the LiSOCl2.


#73

So far so good!

So what do the LiSOCI2 cells cost you to get them to your doorstep? I wonder what the total cost for them would be over a 10-year time frame? Just curious how much cheaper solar charging could be over time vs. replacing the LiSOCI2 cells plus the labor required to replace the batteries.

I was playing around with an image for an online dashboard that displays trash bin capacity levels.


#74

Right now I paid $170 for 10 of them, but this includes $120 shipment. Obviously that shipment is going to become a lot cheaper, and when I requested a quote for 50 it only ended up at $490 ($240 for shipment). I’ve seen them being sold for $20-30 from US retailers though, so if you’re looking for just a few of them probably it’s best to look around some more…but in bulk importing them from China is great.

Replacing batteries should be very simple, since they can be made with the JST-PH2 connector that the Electron uses…that way, if you have a commercial product, you could even just temporarily hire someone to drive around and replacing those batteries with new ones or something. But if the lifespan truly is 2-3 years, then that’s a really really long time :slight_smile:

By the way, those images look great!


#75

Ok, so $10 per battery at 50 unit quantities.

It’s hard to tell how well the battery will stand up to its capacity rating or age over time but we can say it would last 2 years as a worst-case scenario.

Over a 10 year period that’s $50 in batteries plus needing to arrange for a worker to go out and replace them 5 times over the course of 10 years which they can pay a worker to do for free but it will eat up about 10 -15 mins of their time to actually get out and do the swap.

You have to dispose of a toxic battery 5 times over a 10-year time frame also.

I bet a solar panel and battery combo could be added for $15, in higher quantities. The solar panel does not need to be large for this application so it could be a very small custom panel. Something like the Voltaic Systems 1w Panel.

With the low discharge rates, the battery can be small and would last a very long time if a quality cell is chosen.


#76

Checked this morning. Across the 7 devices (2 aren’t downloading the update so I assume 30s isn’t sufficient for them to connect + download - need to find a way to not interrupt its download :weary:), in most cases over a 6-hour period the drop was 0.16%, and 0.33% for a 12-hour period (a few very slight outliers, probably due to different voltages and Fuel.Gauge().sleep). This is pretty much the rate that I was expecting :slight_smile:

As mentioned before though, I’m concerned about using a solar panel. Some of these containers are in the more shifty areas, and I know there have been incidents with complete sensors being stolen…any sort of prop visible on the outside of a container will attract a lot of attention. Also some containers are indoor. The solar panel thing definitely is interesting to consider, it’s just that logistically it can become quite complex as I’d have to deal with different device setups that can no longer be freely swapped between containers anymore (which adds value to the product in itself)…so I’ll give this some thought. Thanks for the suggestion though, I appreciate it, and it does sound like a great idea :slight_smile:

Also, LiSOCl2 batteries should come in today according to UPS, so I’m very interested to see how they are going to perform :smiley:


#77

I hear yea about solar being tricky or not viable in some of the situations. It’s good to bounce these thoughts around.

I’m interested in how well that acrylic is going to work when placed in front of the distance sensors.


#78

Should arrive today by mail as well, will keep you updated on it!


#79

Batteries arrived, and seem to work fine. Went through 10 cycles and each time it could handle the peak currents for establishing a connection just fine.

The acrylic glass was useless - came in already badly scratched (all pieces) and was very easy to scratch myself as well (confused as I specifically asked for pieces with scratch-prevention). I imagine the scratches it came with were caused by the packaging.

The glass obviously didnt work out well with the laser. Will have to look for a different merchant for this


#80

Good news on the batteries.

I have a battery cycle tester that would be interesting to see how the battery holds up with pulse discharges over time.

http://www.westmountainradio.com/product_info.php?products_id=cba4

I will try to find some 1mm thick clear acrylic and laser cut some to test the VL53L0X performance with the acrylic in front of it.

Can you set the Accelerometer to be less sensitive so it only activates when the truck picks it up?