Experimenting with Vibration Sensors

Machinery Safety

I am a cabinetmaker for the past 33 years and my hobby is electronics. I have been in charge of machinery maintenance and first aid for many years. Dealing with the electronics and safety of the machines daily, trying to improve the safe operation whenever I can. Some of the injuries that happen can be avoided with warning sensors. Being in the trade for so many years I have seen the worst, experiencing it first hand, actually my right hand.

Problem:

Working with different machines that require perfect balancing of knives and blades is dangerous. If the machine knives or blades become unbalanced, damage can occur to the machine, or worse, injure the operator. I have experienced this first hand; luckily no one was injured or killed from the incident. We had about 4 seconds of warning before the knives came out of the machine. One of the knives was found almost through a 350mm thick log 10 meters from the machine. I calculated the velocity of the knives coming out of the machine was 255 Km h + or -.

Solution:

This could have been avoided if there was a vibration sensor with an auto shut off. The sensor would have recorded the machine becoming unbalanced and shut it down. I say we had 3 seconds of warning, but a sensor would have picked up the vibration difference before we would have, shutting it down before it’s too late.

Experiments I will perform:

I will use the KEMET's VS vibration sensor to gather information from different machines around the shop while they are running. This will set a benchmark for how much vibration is acceptable out of each one. I will then experiment with setting them slightly unbalanced (in a controlled, safe environment) and get a benchmark for when to shut the machine down. While doing this, I will safely show the power and speed of these machines when something goes wrong. I want to use a relay switch to have the Nucleo-144 send the shutdown command to, when the minimum benchmark is reached. (This experiment will only happen if I get clearance from my superiors). If not, I will create a simulation of this; yet to be determined.

Below is an example of who I will set the experiments up:

The above is a machine called a shaper. It consists of a spindle that knives are attached to and spins at 20,000 rpm. This is the machine mentioned above where the knives came out of. It is used to shape wood into moldings. I really hope my experiments will make a safety impact in my trade.

I want to thank our sponsor Kemet for their support and backing of this challenge!!

Dale Winhold