Screw Removal Machine
At Urban Machine, we designed machinery to automate fastener removal from wood, so boards could be reclaimed from buildings that were being deconstructed. The main barrier to reusing boards is the fasteners because the fasteners will damage the sawblades and planers that are used to turn the old boards into clean usable boards ready for new construction.
I was tasked with solving the issue of removing screws from the wood. While the nails could be removed by gripping the nails with a powerful pincer and pulling out, this does not work for screws – the head just rips off.
Our strategy with was to use induction heating to superheat the screw which then burns the wood around it, making it easy to be pulled out but the nail pulling robot.
This video shows the machine in action. As the wood moves forwards, the coils move to the locations of the screws. When the coils activate, the screws heat up and burn the wood. When all of the screws are fully charred, they board is ready to be sent to the “picker” which pulls the screws out as if they were nails.
Once the idea was proven out, I worked with induction experts to custom design a coil specifically for heating up screws.
After sufficient testing to gain confidence that the process was going to meet our throughput and reliability needs, I started work on the design for a machine that would use computer vision to find and direct the coil to the screws.
I was the “full-stack” hardware engineer on this project. I completed both the mechanical and electrical design of the system. This included:
- motor selection
- linear motion component selection
- machined part design
- sheet metal design
- weldment design
- sensor selection
- computer vision camera and lens selection
- electrical harnessing
- pneumatic design
- safety system design
- electrical panel design