Understood, but this FarmBot is at a school.
What better opportunity and a challenge to present to the students and see how they solve it!
FarmBot seems to me, imho, a wonderful in-road to science, horticulture, robotics, coding, electrical and mechanical engineering, open-source everything and so much more, as well as having a wonderful team of developers and community forum members (You, me and all!).
We will solve the seeding thing, even if I have to have all the kids gather around the robot, watch what it does with evey seed, fix and tweak the code, re-tool the tools and bot and maybe even plant a seed or two by hand!
Wish us luck for “The Great FarmBot Planting Challenge Of 2020!”
Understood, but this FarmBot is at a school.
Hi, we are wondering where the project is concerning the seeding process. We got a farmbot express so we are limited to a single combined tool. We have not found a reliable way to pick up the seeds but placing them is not perfect but seems to be a reasonable approach if you can have a propper tool.
Concerning the pickup process:
We encountered the following challenges:
- the needle would not hit the lowest part of the supplied trough
- when going down into the filled trough, we observed the needle pushing onto seeds and eventually spreading them by flipping the out of the container
- the supplied containers are very small for a complete seeding process of an XL bed
- for fix installed containers (not moving with the gantry) we had problems navigating exactly to the same location again and again.
This is why we make the bot come to a defined location and feed it manually with seeds.
Anyone has found a reliable way to pick up the seeds automatically?
placing the seeds
To place the seeds, we use the following process. It works okay and we have a success rate of 30% to 60%. We are not satisfied with the result, but with adjusted tools and more precise positioning, we are confident to increase the success rate. This is what we do:
- water the positions where the seeds shall go for 500ms each
- poke holes with the needle covered
- release the seed above the hole and set the plant status to “planted”
- run the “poke holes” sequence again to make sure the seeds are all the way down
- run a watering sequence
What is your experience? What works for you?
Thanks for the feedback and sharing of your experience @jensGeorgsen. Something we plan to do to improve the seeding process is use the latest electronics boards to detect when a seed has been picked up by the needle by using load detection circuitry for the vacuum pump peripheral. The hardware for this is in place, we just need to develop the software.
To help with using fixed containers, I recommend placing them near the home (0, 0, 0) position so that the bot doesn’t have far to move from the datum of the home position hardstops.
What seeds are you using that the gantry-mounted seed troughs are not big enough for? We usually see people growing a variety of crops but not that many plants of any one type, so figured the smaller containers would be sufficient for each crop type.
Farmbot suggests using pelleted seeds. I have found the seeds need to be dry and of uniform size and shape. Obviously different size needles with different seeds and be careful not to get the seeder wet it must be dry. I think the seeder tool is something that requires a bit of maintenance over time to make sure stuff doesn’t get clogged or that water doesn’t get into the hose.
Hi @roryaronson, thanks for your suggestions. Detecting seeds is definitely an important functionality.
Concerning the suggestion with the home position: that’s a good idea but it is currently irrelevant for us as we are using an Express model where homing is not implemented yet. We miss homing and we’ll use it once it has arrived…
I think the type of seed is rather independent from the trough size question. Anyhow, we have mostly focused on palleted seeds.
About the size of the troughs
But let’s take radish as an example. We would get let’s say 20 to 50 seeds into one if we are lucky. One radish will take up 80mmx80mm on the grid. That results in 1875 plants for an XL bed (assuming 2000mm x 6000mm in size for this example).
Let’s now assume that we seed in five phases because we are well organized, that is 375 seeds per seeding session or 188 seeds per trough.
This would not fit into the troughs we have received
About the pickup process and mechanism
@whitecaps and @roryaronson: Would you mind describing how you do that (show a video, if you have)? As mentioned, we are using palleted seeds, but we still get all kinds of side effects like spreading the seeds by mechanical force to picking up in the air because there is no seed at the target destination. We did not have problems with a wet seeder or maintenance issues so far.
I am curious to hear about your experiences and suggestions.
I use normal seeds. I tried palleted seeds but I couldn’t source good quality ones, so my seeder tended to break them apart and then bits of the pallet would get stuck in the seeder. I think with better quality ones this wouldn’t happen. I stick the needle right down into all the seeds. Also with normal seeds I can fit a lot more into the seed trough. I use the big seed trough and only plant one type of plant at a time. If I plant up to 3 seeds at a time that’s all good I usually do that when I’m “manual” gardening anyway. Hope that helps.
Thanks @whitecaps! What’s your (rough) pickup success rate with your method?
With that method 45+ seeds using the smallest needle. But results vary depending on the seed type. If you loose vacuum power check the needle is clear, then the hose, then unscrew the pump and clean out the insides of it. I turn the vacuum on before putting the needle into the seeds. I would look into how to make the machine push a hole in the soil first. Others on the forumn have info on that. Then just drop the seed into the hole.
Okay. And when going into the trough 10 times, how many seeds will get picked up?
Ok with lettuce seeds its 1 - 4 each time with the smallest needle for me. Rare to get 4 I aim for 2. Its the same for manual gardening.
With radish seeds or palleted seeds I get one every 2nd or 3rd time. I can’t be sure to get one at all.
What size needle?
One of the bigger ones.
Ok I mostly use the smallest needle. I would check your suction power and there is no blockages. Have you tried what I suggested?
Without trying what you suggest (suppose you’re referring to the cleaning), I tested the suction power. There is no problem there. I think I’ll try to compile a video of my observations. That might give a better understanding of what I am observing. But is it correctly understood that picking up seeds works perfectly for you?
No not perfectly. I don’t often plant 45+ seeds at a time usually max 10-15 and that usually works. If it doesn’t I go through the steps I told you.
Question because I don’t own an Express. Do you have any any spare periferal ports on it?
It would be great to see a video @jensGeorgsen.
Has anyone tried adding a small suction cup on the end of the needle? I’ve seen these used for SMT soldering, for example. They come in a variety of sizes. This is a “larger” from Zeph:
I’ve had similar experiences to the ones in this discussion and I saw that someone else has published a tool also. I didn’t see that previously and I’ve created a digging tool and a hole filling tools and published them on Thingiverse. Hope they are useful to some of you.
Great work. Pity I have an Express. I may need to upgrade it if seeding doesn’t work properly.
Thank you. The improvement was dramatic for me. Its nice to see the seeds dropping directly into the hole.