Sorry for being MIA for a bit. All 120 units are now sold out. I’ve created a waitlist at https://vassarrobotics.com/newsletter to keep you updated on when the next batch will be available (most likely in late July).
Thank you so much for everyone’s support. My top priority now is to get all the orders shipped on time and with high quality.
Firstly, at the $219 price point you can have my money already.
Beyond that, things that appeal to me are basically anything which increase the likelihood I can accomplish high dexterous fine motor control skills, for things like tinkering and DIY assembly. I think that would include extra wrist DOF and a longer-reach variant.
Integrated cameras are an interesting idea, but I'd like to be able to swap them out for my own.
My dream is to have some sort of multi-arm table at home. I imagine holding a circuit board, small component, soldering iron, and wire with four robotic arms I control with shaky hands from my laptop. :D
You need some technical specs on the website. How many DOF does it have? Does it have joint angle sensing? If so, what's the resolution? What's the interface to the servos? What's the payload capacity? Does it have integrated motor controllers? How long is it, and what does the dexterous workspace look like?
As a roboticist, what I'd vote for, in order, is:
- more degrees of freedom
- interchangeable tools, either an actual tool changer (unlikely at the price point) or a fixed bolt pattern with electronic passthroughs
- better joint sensing, e.g. absolute encoders, joint torque sensing
Love this !! I have been searching for a homegrown store selling the so101 and other open source robots. Took me 6 weeks to get my unassembled kit for ~$250 from wowrobo (and it got stuck in inspections at the border). Would be cool to connect to learn more about your plans and offer some suggestions for improvements based on my experience so far.
You should put it on Amazon; we used a robotic arm in one of the classes I taught, and for logistics reasons it was basically the only way we could order stuff. Plus it helps with discovery.
I'm sure there's an extra fee but it's sometimes just impossible to order things if you're a big organization from small sites like this.
Can you explain more how this is possible? For a layman like me, what is happening when you tell the robot to do something and how does it know it's going to the right place?
Wow! Recently my son has been asking about doing a project with a robotic arm, and this looks amazing, especially at the hobbyist-friendly price point. And adding in AI is really cool - and just the thing to really grab the attention of an eight year old boy :) Will these be available in the UK, perchance?
A bit of an aside, but how hard is it to get into building RC aeroplanes, compared to FPV copter drones?
As someone who's long dreamed of owning a robotic camera control arm, but who doesn't have a spare $50K kicking around to buy one, I've been following the development of these kinds of projects with great interest. While this particular arm doesn't look like it would have enough payload capacity or smooth enough motion for the use cases I have in mind, the fact its a couple hundred bucks means something that does what I need it to do for an actually affordable price isn't likely too far off.
Do I understand correctly that chess-moving demo decomposes into:
- you recorded precise arm-movement using leader-arm - for each combination of source- and target- receptacles/board-positions (looking at the shim visible in the video, which I assume ensures the exact relative position of the arm and chess-board);
- the recorded trajectories are then exposed as MCP-based functions?
Bought the kit. Thank you for the great price! Are table-clamps included?
I'm down to buy the kit and build but need some idea for how long it takes. Like, I was able to detail finish and assemble a 3D violin but could not make the time and space to assemble a full 3D printer and had to sell it.
Would you please provide more info on what's involved for the kit? Ranges are okay.
Interesting - I was just thinking the other day that a well implemented MCP server driving a robot with access to a camera could be a really interesting project.
Hey Charles, annoyed I missed out on the first batch, signed up to the newsletter looking forward to the next one!
I thought your product page could use a slightly nicer UI. - I'm building an app that let's people spin up multiple variations of their pages and easily implement new UIs. - I like to put HN websites through it whilst I'm training it up to see if I can improve them.
If you want the html + css, it's here free of charge, I've split each one up with a ## Variation 1/2.. etc.. just let me know what you think - https://pastebin.com/WGNieVmq
The one day I was too busy at work... this came out. Darn.
The price point is crazy good. If it indeed can be so flexible in learning a number of things, just take my wallet. Having an extra hand for N number of DIY projects is invaluable.
I'm curious, since it's a YC/VC company - what's the business plan/model/vision? I assume it's not selling robot arms for $219? (Please correct me if I'm wrong!)
Interesting project! Sorry if I'm out of the loop, but how exactly does the MCP server hand off visual data to an external LLM service to formulate the robot control actions? It's an interesting concept, but I'm having a hard time wrapping my head around how it works, because I thought MCP was text-oriented.
Great product, congrats on the quick sales! Big fan of robotics for a long time myself. If you're in need of some website development, I'd love to chat >>hello at joshmleslie dot com<<
I wonder if I can strap this to my Roborock from 2020 and train it to pick up socks.
Roborock sells a new model that does this [1] but it costs $3,000 and I refuse to pay that on principle when I know it's likely a straightforward model with some unsupervised training.
Also I can probably fix it easier once it (definitely) breaks at some point due to collisions.
I've been looking for a cheap 7 DOF arm. The only reason I haven't bought SO100/101 yet is that it's 6 DOF (and that delivery to Europe is hard to find..)
congrats on the launch. i started selling robots for $100/each back in 2012. (tapster). realized over time, it's hard to stay in business at that price point if that's all you're selling. my bots are now closer to $10K/each. you can probably keep the price low if you have some other part of the business model to fill the gap (consulting or some hosted service or an ai/data play). since you're a yc company, i assume that's the case.
As a related question, is there some way to buy or make plush toys that are robots underneath? I wanted to use a computer to train them and download the program onto the toy, or use wifi to send the telemetry and animate it. The toy would have a microphone, speaker etc.
As another robot hobbyist, I wish there were more detailed documentation on how things work. So many projects online just show a working demo—usually on YouTube—and it's impossible to decipher what’s actually happening, or if the robot is simply following some predefined movements.
I love the idea of a trainable robot arm as a learning device at that price point.
However, seeing the chess demo instantly makes me think of that horrible tragedy with the robotic arm breaking a kid's finger. How strong is this to be used around kids?
I would easily pay $1000-$1500 if you put two of these on a wheel base and made it all structurally sound. Extra points if the arms sit at least 1-2 feet of the ground and can reach the ground.
Launch HN: Vassar Robotics (YC X25) – $219 robot arm that learns new skills
567 points by charleszyong 10 June 2025 | 218 comments
Comments
Thank you so much for everyone’s support. My top priority now is to get all the orders shipped on time and with high quality.
Beyond that, things that appeal to me are basically anything which increase the likelihood I can accomplish high dexterous fine motor control skills, for things like tinkering and DIY assembly. I think that would include extra wrist DOF and a longer-reach variant.
Integrated cameras are an interesting idea, but I'd like to be able to swap them out for my own.
My dream is to have some sort of multi-arm table at home. I imagine holding a circuit board, small component, soldering iron, and wire with four robotic arms I control with shaky hands from my laptop. :D
As a roboticist, what I'd vote for, in order, is:
- more degrees of freedom
- interchangeable tools, either an actual tool changer (unlikely at the price point) or a fixed bolt pattern with electronic passthroughs
- better joint sensing, e.g. absolute encoders, joint torque sensing
- fingertip force sensing
But I’m routing for you!
I'm sure there's an extra fee but it's sometimes just impossible to order things if you're a big organization from small sites like this.
A bit of an aside, but how hard is it to get into building RC aeroplanes, compared to FPV copter drones?
- you recorded precise arm-movement using leader-arm - for each combination of source- and target- receptacles/board-positions (looking at the shim visible in the video, which I assume ensures the exact relative position of the arm and chess-board);
- the recorded trajectories are then exposed as MCP-based functions?
Bought the kit. Thank you for the great price! Are table-clamps included?
Would you please provide more info on what's involved for the kit? Ranges are okay.
I thought your product page could use a slightly nicer UI. - I'm building an app that let's people spin up multiple variations of their pages and easily implement new UIs. - I like to put HN websites through it whilst I'm training it up to see if I can improve them.
here's what my app came up with for your site: https://streamable.com/vbby9q
If you want the html + css, it's here free of charge, I've split each one up with a ## Variation 1/2.. etc.. just let me know what you think - https://pastebin.com/WGNieVmq
It's not exactly on topic (other than fun ideas, begetting fun ideas), but a USB-C/WiFi driven typewriter would be a hoot.
EDIT: Found [0]
And for the reverse ... boom! (click! clack!) [1]
[0] https://www.nutsvolts.com/magazine/article/turn-a-typewriter...
[1] https://www.usbtypewriter.com
The price point is crazy good. If it indeed can be so flexible in learning a number of things, just take my wallet. Having an extra hand for N number of DIY projects is invaluable.
How do I buy your kit, please?
1. Would we be able to control it deterministically via an API, rather than relying on LLM?
2. What is the latency on this? Do you think it would be fast enough in deterministic mode to play ping pong?
Just one question: does the power supply have a 220/240v option (I'm in Australia)?
Roborock sells a new model that does this [1] but it costs $3,000 and I refuse to pay that on principle when I know it's likely a straightforward model with some unsupervised training.
Also I can probably fix it easier once it (definitely) breaks at some point due to collisions.
[1] https://www.youtube.com/shorts/vHVQxXVgBm4
The most important link to get started is probably https://github.com/huggingface/lerobot
Can I order one where I 3d print the in printable bits and you supply the rest. Not to save money but to have a more tweakable design.
Which one is the actual price?
However, seeing the chess demo instantly makes me think of that horrible tragedy with the robotic arm breaking a kid's finger. How strong is this to be used around kids?
I would easily pay $1000-$1500 if you put two of these on a wheel base and made it all structurally sound. Extra points if the arms sit at least 1-2 feet of the ground and can reach the ground.
Congrats on shipping!
I can personally not solder, but I would love to have two arms that can just do it for me.
this page design is so beautiful