I have built a reliable and accessible machine to automate the stringing process for string art. The machine is built with off the shelf electronic components and 3D printed parts. During stringing, the machine runs for about 3.5hrs and can be configured to pause midway to restock thread. It is incredibly low maintenance and runs with optimised controller code to ensure reliability over hundreds of thousands of stringing cycles.
Education
- Teach robotics, electronics and design
- An instructive and rich project
- Let students build the machine & use it
Businesses
- Manufacture string art efficiently
- Unique interior decor
- Can make: logos, portraits, animals
Events
- Live demos & showcases
- High engagement visual process
- Memorable for all age groups
How it works
- Image is processed via custom software
- A stringing sequence is generated algorithmically
- The sequence is converted into motion commands
- The machine autonomously executes the design
- The finished piece emerges over time
Sequence and controller code are uploaded via Arduino IDE
Board snaps onto turntable using custom mounting plate. Motor sits off to side of base board to reduce assembly height
Threading assembly with passive tensioner and servo
Electronics include: microcontroller, stepper driver, DC-DC converters, high spec power supply (with switch), software enabled pause switch
Flexible red tubing bends around nails without breaking (lasts for 5-10 full pieces and easy to replace)
System design
The assembly consists of 3 subsystems:
- High precision turntable. Actuated by a stepper motor with 5:1 gear ratio for increased torque. Uses a lazy susan bearing and 3D printed parts to hold motor and connect to the base. The boards are snapped onto the turntable by a 3D printable mounting plate.
- Thread hooking mechanism. Thread is fed through a tensioner and guided down a small flexible tube which flicks between the nails. This tube can bend around nails without breaking, reducing the need for precise setup and alignment. A servo motor controls the motion of the tube.
- Optional drill unit. I use a motorised drill unit to prepare boards for nailing to ensure evenly spaced angled holes. Nailing must still be done by hand (200 nails takes about 20 minutes).
Software & Control
Software optimisations have been implemented throughout:
- Sequence optimisation (Python). Robust image preprocessing, well designed algorithm and accurate correlation of real results to digital renders ensure sequence is optimal for given image.
- Hardware & electronics. High spec power supply and stepper driver ensures the turntable is always at the commanded position and that it doesn't miss any steps.
- Microcontroller code (C++). Machine always hooks the nail from the best side (to avoid excess wrapping). Velocity profile is applied to the servo to reduce wear. Acceleration profile is used on the stepper to improve speed while ensuring steps aren't missed.
Enquiries
If you are interested in this machine then please contact me and explain how you would want to use it (e.g. manufacturing string art, educational purposes, live showcases etc).
Physical units currently only available in the UK. The machine is designed for technical users in a supervised environment. Future improvements can be made (i.e. enclosure, GUI).