In this project, I’m going to show how I set up a simple indoor asset tracking system using ultra wideband modules. This is the same kind of technology used to track tools, machines, or robots inside a building, and I’ll be testing it by tracking an RC car as it moves around a hall.

The idea is to place a few fixed devices called anchors around a space and then track a moving device called a tag. By measuring how far the tag is from each anchor, the system can figure out its position in real time. It sounds complex, but once you see how the pieces fit together, it actually makes a lot of sense.

All of this comes as a single kit from my friends at Reyax, called RYUW122_DK, and I’ll walk you through the hardware, the basic setup, and how everything talks to each other over WiFi. By the end, you’ll have a clear picture of how this kind of tracking system works and how you could adapt it to track equipment or projects in your own space.

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RYUW122_DK Development Kit

The development kit comes in a pretty large box, and once I opened it up everything was neatly packed inside. Right away, I could see four RYUW122_ANCHOR1 anchor boards, a couple of smaller light RYUW122_Lite modules that are used as tags, and all the cables needed to connect everything to a computer. There’s also a USB flash drive included that has example software with its source code, which is really helpful if this is your first time working with this kind of system and can very easily kick start the development of your system.

Along with the main boards, the kit includes USB to serial adapters and some jumper wires. These are used later when setting up the tag module, so it’s nice that they are already included and you don’t need to buy anything extra. Each board feels solid and clearly labeled, which makes it less intimidating when you first take everything out of the box.

Overall, the kit is designed so you can go from unboxing to testing without hunting down extra parts. Having all the anchors, tags, cables, and software in one package makes it much easier to focus on learning how the system works instead of troubleshooting missing hardware.

Understanding Anchors and Tags

Before setting anything up, I want to explain the basic idea behind anchors and tags because this is the heart of the whole system. The anchors are boards that stay in fixed positions around the area you want to track. Each anchor knows where it is placed, and it never moves once the system is running.

The tag is the device that moves around inside that space. It talks to all the anchors and measures how far away it is from each one. By comparing those distances, the system can calculate where the tag is located. I like to think of the anchors as reference points and the tag as the thing we are trying to find.

In my setup, I use four anchors placed around the edges of the room and one tag mounted on an RC car. As the car moves, the tag keeps updating its distance from each anchor, which lets the system track its position in real time.

How the Positioning System Works

To understand how the positioning works, you can imagine the room as a simple rectangle with an anchor in each corner. Since the anchors are fixed, the system already knows the distance between them. This creates a known area where anything inside can be tracked.

The tag measures how far it is from each anchor using ultra wideband signals. These distance measurements happen very quickly, and the system collects them from all four anchors. Once it has those values, it can calculate the exact spot where the tag is located inside the space.

This process repeats many times per second, so when the tag moves, its position updates smoothly on the screen. Even though a single tag takes a short moment to be fully calculated, the result feels almost real time and is accurate enough for tracking machines, robots, or other moving equipment indoors.

Setting Up the Positioning Server

To make everything work together, I first set up the positioning server on my laptop. This server is the part that receives distance data from the anchors and turns it into an actual position on the screen. It runs as a simple program provided with the kit, so there is no complicated installation involved.

For my test, I used a WiFi hotspot from my phone and connected both my laptop and the anchors to that same network. Once I started the server, it showed me the IP address of my laptop and the port it was using. This information is important because every anchor needs to know where to send its data.

After the server was running, I left it open in the background while moving on to the hardware setup. As soon as the anchors connect to the same WiFi and point to this server, they automatically start sending data, which lets the system calculate positions in real time.

Configuring the Anchor Modules

To configure each anchor, I connected it to my computer using a USB cable and opened a serial tool, Docklight, recommended by Reyax. This tool lets me send simple text commands to the board so I can change its settings. The first thing I check is that I selected the correct serial port, since that can change depending on which USB port I use.

Each anchor needs to be set to anchor mode, and they all must share the same network ID so they can talk to each other. I also give every anchor its own address, like anchor one, anchor two, and so on. This is important because the server needs to know which anchor is which when it receives data.

Once the mode and addresses are set, I configure the WiFi connection by entering the network name and password. After that, I tell the anchor to connect to the positioning server using the IP address and port from my laptop. When I see the anchor show up on the server, I know that one is ready and I repeat the same steps for the remaining anchors.

To make things easier, an example script is also provided with the kit so you can just modify it with your parameters to make it work.

Configuring the Tag Module

After all the anchors are set up, the next step is configuring the tag that will actually move around. For this, I use the small light module and connect it to my computer with the USB to serial adapter that comes in the kit. I make sure it is powered with 3.3 volts and that the transmit and receive pins are connected correctly, since those are easy to mix up if you are new.

Using the same serial tool as before, I connect to the tag and change its mode from anchor to tag. This is usually just a single setting, but it makes a big difference because it tells the system that this device is meant to move. I also set the same network ID used by the anchors so everything stays on the same system, and I give the tag its own address so it is easy to identify later.

Once those settings are saved, the tag is ready to talk to the anchors. At this point, it does not need WiFi on its own because it sends its distance data through the anchors to the server. When I power it up, I can see it appear in the positioning software, which tells me the tag is configured correctly and ready for testing.

Placing Anchors and Setting Distances

With all the devices configured, I move on to placing the anchors in the space I want to track. I put one anchor in each corner of the area, making sure they stay fixed and do not move during the test. The exact placement matters because the system assumes these positions are known and constant.

Next, I measure the distances between the anchors. I enter these values into the positioning software so it understands the shape and size of the space. Two anchors share the same horizontal distance, and two share the same vertical distance, which makes the layout easier to define and visualize.

Once the distances are set, the software draws a rectangle that represents the tracking area. This step is important because all tag positions are calculated relative to this layout. When this part is done, the system is ready to start tracking movement inside that defined space.

Testing the System on the Bench

Before taking everything to a larger space, I wanted to test the system right on my workbench. I place the anchors a short distance apart and enter rough measurements into the software. This setup is not meant to be very accurate on such small distances, but it helps confirm that all the devices are talking to each other correctly.

Once the anchors are active, I power up the tag and select its address in the positioning software. Almost immediately, I can see the tag appear on the screen inside the drawn area. When I move the tag by hand, its position updates, which tells me the system is working as expected.

Even though the tracking is a bit jumpy at close distances, this quick test is very useful. It lets me catch wiring or configuration mistakes early, before I spend time setting everything up in a real environment.

Real World Test With an RC Car

For the real world test, I moved everything into a large hall and spaced the anchors much farther apart. I placed one in each corner of the room and made sure they were stable and powered. Then I attached the tag to the top of an RC car using tape, which is a simple but effective way to turn it into a tracked object.

With the positioning server running on my laptop and connected through my phone’s WiFi hotspot, I started tracking the tag. As the RC car drove around, I could see its position updating on the screen in real time. When the car moved left or right, the marker followed it almost exactly, which was very satisfying to watch.

I even drove the car slightly outside the area formed by the anchors, and the system still kept tracking it. This showed me that the range is more than enough for indoor use and that the setup can handle real movement, not just small bench tests.

Final Thoughts and Use Cases

After seeing the system work in a real space, it’s clear how useful this kind of setup can be. What started as a simple RC car demo easily translates to tracking robots, tools, or machines inside a building. Once you know the position of something, you can use that data for navigation, organization, or automation.

The nice part about this kit is that it lets you focus on learning how indoor tracking works without designing everything from scratch. With the anchors fixed in place and the tag doing the moving, the whole system feels reliable and predictable. Even with a beginner level setup, the results are surprisingly solid.

If you are looking to experiment with indoor positioning or asset tracking, this is a great way to get started. You can begin with small tests like I did and then scale it up to larger spaces or more complex projects as you get comfortable with the technology.

If you enjoyed this project and want to see more beginner friendly electronics builds like this, make sure to subscribe to my YouTube channel so you don’t miss the next one.

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