Opinion Robot Arm

Robot Arms and the Recycling Problem

Recycling in the US is collapsing and low cost robot arms like Sixi can help prevent disaster. The buyers of recyclables demand pre-sorted material with almost nothing mixed in. The suppliers are finding the cost to sort is astronomical. While much of the sorting is done by machines already, the job could be done even better with tireless robots.

How recycling works

Typically when you drop recyclable material in the blue bin it goes to a facility where it is crushed, packaged in bulk, and sold to a buyer that can repurpose the material. The largest buyer for canadian and american recyclables is China.

Recycling buyers have tightened standards

“As of Jan. 1, 2018, China, which buys approximately two-thirds of North America’s recyclables, requires that contamination levels – newspaper smeared with ketchup, plastics mixed with broken glass – can’t exceed 0.5 per cent as part of its National Sword initiative.” — The Globe and Mail

Humans sorting is too expensive

” A study by Rob Taylor with the State Recycling Program in the North Carolina Department of Environmental Quality estimated that the average market value of a ton of mixed recyclable material arriving at a recovery facility in the state dropped from just over $180 in early 2011 to less than $80 at the end of 2015. That value has since rebounded a bit, Taylor found, to a little over $100, but it still leaves the industry struggling to extract profit from the millions of tons of recyclable material Americans throw away every year. ” — USA Today

New solutions in High Tech

There are still buyers! The cost to prepare the has gone up, which lowers the return on investment for anyone trying to do business with recycling. Any technology that can lower the cost of recycling is a worthwhile purchase for these businesses. Let’s consider a typical recycling scenario and apply some new technology to the challenge. Suppose a pile of mixed recycled material being fed onto a conveyor belt.

The first problem is to identify the material so that it can be sorted. Computer vision and AI has been making major strides in recent years. Have you seen the Tesla’s object identification? Or VACnet, Valve’s anti-cheat system? Pattern recognition is something Deep Learning does really really well – in many cases, better than humans. In the early days it starts by having a Deep Learning system watch humans sort recycling while it learns what goes where. Soon enough, it knows enough that it should be able to spot things humans missed. Best of all, the Deep Learning doesn’t need to be retrained – it’s an employee that works forever and only gains experience.

The second problem is to physically separate the material that has been identified. This is where robot arms come into play. They don’t even have to be fast – if the arms are too slow, throw more arms at the problem!

Why aren’t robots recycling today?

The 2019 price of low end industrial robot arms is north of $10k USD each. Lowering the cost of robot arms will speed adoption. It is a worthwhile goal for a company that looks to the future and cares about the fate of the world.

There is no question that we have to do it. By lowering the cost of robotics we can raise the profitability of recycling and encourage less landfill. Until the world learns to stop making garbage, Marginally Clever Robots hopes to fill the gap and provide the low cost robots to help prolong the human experiment. Our customer base should be 7 billion strong.


Weekly summary ending 2019-03-08

Hey, gang! Happy International Women’s day. On my birthday women celebrate around the world. That never gets old. Something something my ego.

Jin is down with seasonal allergies/mild death and we don’t have our amazing interns any more, so this week has been a little rough.

New! ELEC-0134 Sir Ramps-a-lot Dark Knight

We use the sir-ramps-a-lot board so that our Mega/RAMPs combo can easily control external drivers. Some of the drivers we purchased decided to be contentious and are designed with all their signals reversed, so we needed a sir-ramps-a-lot that was ALSO reversed. Anyways, here it is!


Robot Overlord Adds Sixi Robot Arm

The inverse and forward kinematics are both working great, which means you can move it either way and switch between the two as you see fit. Making the IK and FK code work took me three whole days of agony, so there’s not much progress in other areas this week.

Sixi Robot Rendering

This is pretty close to our vision for the robot. We’ve had it assembled and we’ve even got it moving, but I’m not ready to show it to the world just yet. It’s coming together! I would love to show you some action shots we’ve taken… but these PR things have to be handled just right, you know what I mean? Patience is a virtue.


Now the challenge is to program waypoints and paths (all the beziers!) to build higher-level applications for the arm. Meanwhile Jin is stress testing the cycloid gearboxes and coming up with new ways to make them even better-er.

Cool! So subscribe to this blog or our Youtube channel OR our Instagram for all the latest and I will see you next time!


Weekly summary ending 2019-03-01

Hey, gang! Here is what we worked on in the last week, where we are heading next, and how you can join us.

Makelangelo whiteboard hooks

The hooks for mounting a Makelangelo on a whiteboard that Jacob designed are now on Thingiverse. If you can’t print one or you’d like it included with your purchase of a robot, get a set of hooks today.

Makelangelo drawing on glass

Now that the DaGhizmo pen holder is standard I’ve been playing around with drawing on glass. Check it out! I used a pink EXPO Brightstick.

If you’re feeling a little left out because you have an older pen holder made of acrylic or wood, fear not! We have your new pen holder ready.

Sixi Robot knolling

We took the robot apart after some motion testing to inspect the hidden parts. We want to be certain everything inside is good. Turns out the shaft couplers were giving us grief (again). Our next version of the collars won’t even have a split on one side. Instead they’ll be friction fit with a set screw that goes into a hole on the side of each tube.

Sixi Robot electronics enclosure

We have had great fun with our electronics enclosure. I’ve only tried to make one enclosures before. We used an off the shelf enclosure that has nubs in the bottom. The idea is to design a plate that has one set of holes for the electronics and one set of holes that match a few of the nubs. Even when we followed the Original Equipment Manufacturer’s (OEM) data sheet, we still couldn’t get our laser cut plate to line up with the nubs. That left everyone here scratching their heads.

The box hole pattern
making sure parts fit in the box


Jacob and Scott have finished their internship with us. 😭 With luck we can have them back over spring break or the summer. I say with luck and what I mean is “with luck the Sixi is done”. There’s already so much to do here but that is where I want to delegate them, working on the new bleeding edge of technology with the new hotness.

I would write more but I have to get back to it! There’s firmware to update for the Sixi and components to reassemble. Subscribe to my channels and buy some of the good stuff so we can keep being awesome, k? K. Peace out.