smiller29
The Birth Of The XR-1 DIY Robot
Introducing the Updated XR1 and the New XJ-5: A New Class of Hobby Robots
The XJ-5 robot platform, available at Robots Builder, stands out for its user-friendly design, emphasizing accessibility and ease of assembly. Designed to make robotics more approachable, the XJ-5 is meticulously engineered for easy 3D printing and assembly with standard parts like servos and bearings.
Our goal is to simplify the building process so that enthusiasts and robot hobbyists of all skill levels can engage in constructing their own robots. We've invested time in perfecting the design, ensuring that users can quickly move on to the exciting tasks of programming and teaching their robots using Synthiam ARC. The XJ-5 is highly customizable, featuring a variety of hands and heads to allow personalization of each creation. To encourage a collaborative and open community, we're proud to announce that the XJ-5 is entirely open source, inviting users to contribute, modify, and share their innovations globally. Get ready to embark on a journey of creativity and exploration with the XJ-5!
For more information, check out Robots Builder.
As a creator of the XJ-5 and our other XR series, I will be leveraging the Synthiam ARC platform for robot control, and I hope others here will join me in developing an ARC project to support the XJ-5 robot. As of January 9th, 2024, we have started posting files for 3D printing. Meanwhile, we are developing documentation and the above website, so please check back regularly.
My goal is to have a walking, talking, listening, and seeing robot the size of a small child using ARC and its various skills. As I progress, I will be sharing more about my efforts here.
Now, let's dive into the project focusing on the new and improved XR1, the XJ-5, which I have been designing and building over the past year.
As a young enthusiast, I loved the movie Short Circuit and fell in love with the Johnny 5 robot, inspiring me to create a similar robot. It was not designed to replicate the original Johnny 5. About a year ago, DJ suggested preferring a robot with wheels or tracks over a bipedal robot due to the complexity of making them walk, a challenge I am familiar with from our XR2 project. But hey, that's another story.
Now, in May 2025, I've almost completed the assembly and will start implementing ARC and the AI brain I've been working on to support ARC. More updates will follow.
I have started building the torso from the hips up, as shown in the pictures below. The shoulders are not fully installed because I'm waiting for the correct screws to arrive. Please excuse the messy workbench.
To support the robot, I have designed a set of boards with ARC firmware that will connect to the onboard PC, which will be situated in the middle of the chest.
The above board will be mounted on the backplate between the two shoulder sockets and connected to the USB hub that will be connected to the PC. Two more USB cables, along with servo power, run down to the boards in each hand. The USB camera and headboard will be connected to the PC's other two USB ports. ARC will run headless on the Windows 11 Pro PC using RDP for remote connectivity. Additionally, there is an MPU connected to the main board that I plan to leverage with ARC.
I have added the shoulders and arms down to the wrists, and they appear to be strong and capable.
I decided to create a Johnny 5-style head for my build featuring two cameras. Here is the completed head. I have added six more servos to the build for the eye flaps, bringing the total count to 50 servos. It includes a directional mic array and ultrasonic radar for enhanced audio and visual capabilities. For sound, two speakers are mounted in the head with an audio amplifier.
I have also decided to add an option to the XR-1 to support a 5-inch touch display, as shown below.
The display will provide more options for operator interaction using ARC remote controls.
I have created both two and three-finger claw grippers and human-like hands, providing versatility in interaction for the XR-1.
So DJ If I am understanding you that you are recommending the Rplidar (A1) out of all the ARC supported options?
I’m recommending any of the supported lidar combined with the better navigator as I said above.
*edit; just make sure it works with the NMS. The rplidar a1 works with NMS and is good. It’s what I use. You can learn all of this faster by reading the page I provided and following the video tutorials. All I’d be doing is repeating what’s already there.
Thanks I read all that and the related links
Your conformation helps DJ with product choice. I just need to figure out where to mount it on the above track design. I would think it should be located on the lower section of the robot to the front but I can't see a way to give it a 360 view. I need to think about this because this is a real nice solution and I would love to have it built into this robot.:)
So What do you think about this location? I need to make space for it and add some protection for it.
It’s 360 degrees. So you can block part of it, but not over half of it. The more data points the more accurate. Mounted in that position will not perform at all.
it spins and gets distances in 360 degrees.
you can block less behind it by mounting it higher. Or have one in front and one in back.
So if it has at least 180 degree scan area above the tracks on each side would that work? Also how high off the floor should it be scanning?
Height from floor depends on your environment.
As for blocking - thats hard to say. I wouldn’t block directly in front. But it’s okay to block a few degrees behind.
@athena give @smiller tips on where to place a 360 degree lidar rplidar a1