Ultrasonic Sensor Regulable Mount

Hi! I´m Alejandro. I am in 8th grade and I am a student at the technological institute IITA.

For this competition I´ve made a regulable mount for an ultrasonic sensor for robotics that can be attached either to the robot directly or to a servo, and I´ve implemented a version of it in one of my projects (All my projects can be found on my instagram: https://instagram.com/alguienmuyrobotico ).

All designs can be found in my Tinkercad: https://www.tinkercad.com/users/bn0FkXVLAYJ-alguie...

You may want to design this piece yourself considering that some sensors may vary slightly in size.

Computer

3D printer

Long m2/m3/m4 screw (around 3cm long) and nut

Low grit sanding paper, small file or equivalent

Ruler, caliper or equivalent

Files for this piece:

Go to shape generators, then click featured an insert an extrusion. Shape it until you have a similar shape to this one that you are happy with. Now, scale it to around 32mm tall, 28mm wide and exactly 8mm deep.

Measure the lenght of your bolt and subtract it 3 to 4mm. Create a cube and give it that measurement in lenght, also make it 28mm wide and 4mm tall and position it so that it covers the round bottom part of the extrusion.

Duplicate the extrusion and save a copy for later, then duplicate it again and put it in the other side of the base and join all together. Measure the diameter of your bolt and make a hole with that plus 1mm of clearance as shown in the image. Then measure your nut, make an hexagon with those measurements and substract it from the end of the hole on one of the sides. Do the same for the head of the scew in the other side, but this time with 1mm of clearance. If you can´t get them to align with the center of the hole, change "snap grid" to 0.5mm.

Now you have to decide if you want to use this mount with a servo, directly attached to the robot or both. If you are only intrested in the servo part jump to the next step.

To attach it with screws make the holes in the part with the diameter of your screws plus 1 to 2mm of clearance as shown in the image. Then do the same for the hole for the head of the screw. Do it so the bottom of the cilinder is at the height of the top of the base cube/prism.

You can also just glue it.

To mount it in a servo, search for a model of the servo head you´ll use an substract it from the base of the part, then clean up with more holes any litle points or imperfections in the center hole.

Since all ultrsonic sensors are similar but not equal, be sure to use the measurements of your particular sensor and not a 3D model from the gallery for this part.

First create a cube and size it 56mm wide, 30mm deep and 4mm high. Then bring in the extra extrusion from the first part, make it the size of the middle gap from the previous part and put it in the center of the cube/prism.

Measure the lenght and width of your sensor and make a cube with those measurements plus 1 or 2 mm of clearance and 4mm deep, duplicate it and save a copy for later. Then divide it in two with the space in between large enough so that the pins fit with no problem. I've found this distance to be around 14mm.

Place the part in the face of the previous one as shown in the pictures.

To finish, make the hole for the screw with 1mm of clearance as shown in the picture.

Create a cube with the same measurements as the base of the previous piece and around 17mm deep.

Then take the previously saved cube and make it 11mm deep and substract it from the other cube with no clearance, since it will be a friction fit to eliminate the need for aditional screws. If you want to save yourself some sanding, leave a little clearance and then see if they hold toghether just like that or, if not, just glue them.

This is the part in wich is important that you measure your sensor. Make a cilinder with the diameter of the trigger and receptor on you sensor plus 1 or 2mm of clearance. Then duplicate it and separate them by the exact distance between the two on your sensor. Put them in the exact center of the indent in the part and substract them from it.

Lastly, make a hole for the pins to pass trough in one of the sides of the part as shown in the pcture. DON'T do like me and make it 10mm wide; make it around 14mm wide and 4 to 5mm deep.

By now you should have something similar to the first picture. I printed the parts in PLA, at 0.3mm layer height with 30% infill and it worked perfecly. If you noticed that there is no hole for the pins in the image it´s because I forgot to make it and had to reprint the part.

To assemble it, first check that the ultrasonic sensor fits in the last part. At first the two parts that go together won't fit; sand the part of the back until they do but still stay together. Here you can regulate how hard do you want them to be joined. Do the same for the first and second part until they rotate a bit smoother.

Enclose the sensor, insert the nut in its respective hole (You can also glue it in place if you want to) and insert the screw from the other side.

Congratulations, you've completed the piece! Now just screw it or glue it in place or fit it and glue it to a servo head. Move it to the desired rotation and tighten the scew to lock it in place.

You can pass the cables for the pins trough the gap in the bottom of the hinge, or if you need it to be completly down, flip upside down the last part and the sensor and pass them trough the top.