3D Printed Tags

Today is a proud day here at HLH, we are deploying the first set of our brand new, 3D Printed RFID tags. We are now making our own nursery stakes with embedded tags right here in my office. The final product are sheets of 15 stakes that measure 115mm x 17mm x 1.5 mm constructed of ABS plastic with a UHF RFID inlay embedded between two layers.

RFID

A CS101 RFID reader scanning one of our nursery tags.

What is it?
RFID stands for Radio Frequency Identification. An RFID system at its most basic includes an antenna, usually called a "tag", and a reader. The tag is small and capable of holding encoded information. When activated by the reader the tag "wakes up" and reports its encoded data. This is of course an oversimplification and there are 100s of variants when it comes to antennae and readers and their capacities, but this is generally the idea.

Who uses it?
The US Department of Defense and Wal-Mart are two of the biggest users of RFID technology. The DOE uses it for asset tracking and Walmart for retail inventory control. RFID is used by thousands of retailers. Those big security pylons you walk through when entering and exiting a store are RFID readers, and the anti theft tags on garments and other retail items are RFID antennas. RFID is now being used in a variety of innovative applications in thousands of working and production environments.

What can RFID do for reforestation?

Seedlings with RFID tags

Darrell Fox, COO of Hawaiian Legacy Hardwoods chose RFID as a way to track and identify our reforestation Legacy Trees for a variety of reasons. A big plus is the fact that an RFID tag is readable without achieving a line-of-sight. This is great for an outdoor environment where tags are placed in the ground next to seedlings. The grass at Kukaiau Ranch (where our Legacy Forest is located) is aggressive and quickly covers the tags making them very difficult to find. If we were using human readable or barcode tags it would take us way too long to find a tag to identify the tree. With RFID we simply point the reader at the base of the tree and pull the trigger. Like magic.
Another advantage is the longevity of some RFID tags. Because the antenna itself is metallic these tags can be made to last a very long time. This is helpful for a forest that we hope will be permanent.

Having a way to verify and identify every individual tree in a forest means big things. It means you can quantify how much carbon that forest sequesters. It means you can track an investors individual trees until harvest. It means you can know exactly where every tree is and collect data on every event in that trees life. The implications are sometimes overwhelming and everyday we are discovering more we can do with our forest technology. 


Our nursery tag development.
 Our application of RFID is unique. There is no "out of the box" solution for a "Reforestation RFID Tag." So we make our own. Early in the project we were buying plastic tags and adhering them to plastic nursery stakes. We then coated this assembly with roofing compound to weatherproof it. Then the tags were encoded, one at a time, using the handheld RFID reader. This method soon became too time consuming as our plantings progressed and we purchased a Zebra R110Xi4 RFID printer and rolls of tags that were in label form, adhesive included. This gave us the ability to pre-encode the tags at a rate of 100 per min. before adhering and coating. 

Freshly dipped nursery tags.

     At HLH we love to innovate and we all strive for progress and constant improvement. Our goal is to build a model for reforestation that is both economical to launch and fiscally viable enough to sustain itself, making reforestation an appealing alternative for large landowners. To this end we are still developing our tags to find the perfect balance between function and cost.


 3D Printing
 The latest advance to our process was to add twin Lulzbot 3D printers to our manufacturing chain. These printers extrude hot, softened ABS plastic in very thin layers to build a three-dimesional object. Pretty awesome.
Using the printers we can now eliminate 90% of the labor and 2/3 of the costs in production of tags. We are able to skip the messy dipping process and we feel we have a superior tag now.
In a nutshell the process is as follows: We print out one half of the tag, pause the printer, apply the RFID label, pre-encoded, and the print the rest of the tag. With proper arrangement we can fit 30 tags on each printer at a time. The printers also allow us to make custom tags, adding 3D logos, images, colors, textures etc. The world of 3D Printing is rapidly growing and we expect better and faster tags every year. The material available to print in is also expanding. We are expiramenting with a wood composite filament that will allow us to print custom tags (and anything else we can think up) in a wood form.

RFID Readers
Just as there are no off the shelf tags for reforestation there are no stock readers that do exactly what we want and still stay at a reasonable cost. So once again we are developing our own. When we scan our trees in the field we are obtaining the data from the RFID tag but we are also obtaining a GPS coordinate. The readers that can accomplish this are very expensive and only do it as a kind of workaround/hack. We have had many frustrating days in the field where a reader has crashed, losing a days worth of collected information. Darrell Fox is hard at work on our first model, in the form factor of a metal detector. This will keep the RFID antenna close to the ground, where the tags are, and set the GPS antenna higher up towards the handle, reducing the chance of signal loss. 

We are excited to see what the future holds for our RFID program and as the technology grows we intend to grow with it, always striving to be at the cutting edge of forestry tech. \


The time-lapse video below shows a single tag prototype being printed.

Aloha!

Aloha!
Welcome to the Legacy Forest Tech Blog, a repository of articles about the developing forestry technologies being created by Hawaiian Legacy Hardwoods.
My name is Wil Gilliam, I am the Chief Information Officer at HLH. Ive started this blog as a way to keep track of the myriad of technologies we are working with and to provide an opportunity for others to share in what we are doing. My hope is to not only better organize my own thoughts on these topics but also to engage people around the globe who may be working with similar systems either in forestry or unrelated sectors. Maybe we can learn something from each other. A great deal of what we do here is only possible through the work of other individuals and companies who have made their technology available to the world. In the spirit of the open source movement I will attempt to show how tech can be used to improve the planet.

Please feel free to contact me or comment on any article. These are issues that fascinate me in my personal life as well as professionally so I am always happy to talk nerd-story.