Maker Tip: Labels on all your Custom Pieces

February 27th, 2015

I’m a big fan of Kaizen, the process of continual refinement. Opportunity is everywhere if you’re looking for it. Sometimes it’s obvious like “hey man, I think you should put a link to X on page Y of your tutorial!” …Ok! Sometimes it’s more subtle, like when a customer on the phone tries to describe a part for which they have no name.

On the good suggestion of Sarah Petkus​ of RobotArmy I’ve started putting part numbers right on all my laser cut pieces. Now I realize it was a hole in my inventory control system. I had a separate inventory number for every item in the store, but the laser cut parts were clumped together as “laser cut parts for kit X”. Now that I have separate part numbers I can… Read the rest of this entry »

How to code the Inverse Kinematics for a SpiderCam or SkyCam

February 26th, 2015

Büşra wrote in through the live chat to ask “I’m a student of Mechatronical Engineering in Kocaeli University, in Turkey. My senior project is ‘Skycam‘. I’ve been trying to find this equations for a few months but I couldn’t reach any result. Can you help?”

Yes! Yes.

Skycam test rig
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Yale’s Open Hand Project

February 25th, 2015

Yale Open Hand Model T

If you know me, you know I’ve been obsessed with robot arms for a long time. People ask me “what will you put for a hand?” and I used to say “Who cares? It could be any tool you like.” Well, now I have a better answer.

Yale’s Open Hand Project aims to make an open source robot hand that anyone can download and build. It even comes with adapters for several popular robots already on the market.

I think my favorite part is their Hybrid Deposition Manufacturing (HDM) technique: The finger bones come out of the printer with built in pockets into which you pour a urethane solution. When the urethane hardens to a rubber consistency, the pockets break open and you’re left with a 2-material, super flexible shape. Genius!

How do I program a Joystick and what is a Deadzone?

February 24th, 2015

A photo posted by Dan Royer (@imakerobots) on

Today I want to show you how to use a joystick with an Arduino and why you’ll need to know what a Deadzone is for. Read the rest of this entry »

How to calculate the length of Stewart Platform actuators

February 23rd, 2015

Patrice wrote in to ask “If I know the pitch, roll, yaw, heave, sway, and surge of a stewart platform… how do I then calculate the length of each actuator?”  Great question, Patrice!

I’ve never tried explaining this before in detail, so bear with me. We’re going to use math you probably learned late in high school, so get out your graph paper and erasers and come along for the ride.
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Little Big Planet Sackboy faces with the Arduino Starter Kit

February 18th, 2015

I’ve just wrapped up my 12 sessions with students from West Point Grey Academy.  Parting is such sweet sorrow.  Their final day’s project was to create their own version of Little Big Planet Sackboy faces with the 8×8 LED grids and a joystick a lot like a Playstation or XBox.  In previous classes we wired up the LEDs and learned to control individual lights, how to draw pictures on the screen, and how to use the joystick.  Those parts all come together here to make five emotions based on which way you push the joystick.  The emotion stays on the screen until you push the stick in a new direction. Read the rest of this entry »

Post later today

February 18th, 2015

I’m teaching my last class at West Point Grey Academy this morning, then testing a gearbox I had designed.  I’ll have a post some time later today.  Watch the twitter feed for an update.  Thanks!

Arm3 instructions update

February 17th, 2015

arm3 base assembly

If you follow us on instagram you’ll see last night I shot ~15 photos in a row as I assembled an Arm3. Those pictures have now been added to the Arm3 assembly instructions to make things easier.

A more subtle new feature is that the laser cut files have been updated. Every wood part has a unique number in the design, and those numbers were written next to each part on the wood, a bit like the plastic scale models I assembled as a child.

These kind of parts were my inspiration for numbers on the side.

These kind of parts were my inspiration for numbers on the side.

I felt that it would look better if the part numbers weren’t visible on the final assembly. I’ve been taught the error of my ways, in no small part thanks to your awesome feedback. The designs have been reworked and now the part numbers are directly written onto each part. This way they are easy to identify, even after they’re popped out of the frame. It’s as minimal as it can be without sacrificing utility. I like it, it’s good.

3D Printer Bed Levelling with an Inductive Sensor

February 16th, 2015

protobuilds' inductive sensor

My friends Marshall and Gabi over at Protobuilds in Austin, Texas, heard about my experiments with a bed leveling switch and took it to the next logical step: a touchless inductive sensor. No more screws, no more physical limit switches, no more bed levelling problems!

Read a complete write-up on Thingiverse and try it for yourself!

Now if only someone would add linear encoders so we could get closed-loop printing…