I am working on a capstone project for my mechanical engineering degree. Our design is an attachment for dental drills that will detect the drilling depth as the procedure is happening and will notify the dentist when the correct drilling depth is achieved. In order for the design to detect the drilling depth (up and down linear movement) there must be a sensor that can measure how deep the drill has moved down into the tooth. This sensor will be wired to a wifi enabled microcontroller which will send the data to an iot platform that is integrated with matlab to process the incoming data. We need to provide a proof of concept as ar real prototype is out of the question due to covid.
TL/DR: Is there a sensor small enough that can be attached to a dental drill that can measure linear position (up and down)?
You asked the question very generally, there are many ways to measure the depth, but for your work I do not think there is a built-in sensor so you have to make a sensor. What is the approximate diameter of the hole for this? How much space do you have? I need to see a technical drawing of the drill and the mechanical structure so I can give you an idea for the sensor
I agree with Mostafa Zamanizadeh , Omron has some small range proximity sensor with 1mm scale sensing ranges. Might be suitable for a prototype.
Hi Nikhil Patel ,
I guess the main problem here is that the material below the reference surface can be a natural tooth, more or less wet, or a tooth filling, maybe containing metall, maybe not. This material does not form a plane but the hilly surface of the chewing area of a tooth. To make things worse, I think that modern dental drills usually spray water onto the working area.
These circumstances seem to exclude capacitive sensing unless there is a thin metallic sheet attached springily to the drill handle, supported by the surface of the tooth, and representing the reference plane.
With the metallic sheet mentioned above, either forming a ring with the drill at the center or being reduced to the tip of a spring or to the two tips, located on either side of the drill, of a V shaped spring, instead of capacitive sensing you could also try to measure the bending of the suspension / spring by using a very sensitive, mechanically weak strain gauge.
Optical sensing might be possible if you succeed in filtering out the effect of water spraying. If the dentist would always hold the handle of the drill in a certain angle to the line of teeth resp. the line of the jaw, perhaps the simplest solution would be a row of light sources and a row of light receivers, both rows aligned parallel to the drill, forming a number of light barriers in different heights. But this would not work when drilling into the flanks of teeth.
You can think of using MEMS based optical sensor which can fit into the dental drill and with the help of the fibre optical device measure the instantaneous linear displacement.
Wouldn't a hall-effect sensor work for this? It is used as a position sensor and does not come into contact with the item being measured.
https://en.wikipedia.org/wiki/Hall-effect_sensor
Hi Marc Poland , using a Hall sensor would require an inhomogeneous magnetic field of known relation between position and field strength. For example, one had to fix a short flat permanent magnet on the surface of the tooth first in such a way that the area around the drilling hole is unobstructed.
- Badges
- Science topic
- Similar topics
- Engineering
- Mechanical Engineering