Tuesday, March 31, 2015

2015-03-30 (M) Self Contained Haptic Distance Sensor

The first draft of the Arduino code was written. The code was written using the distance sensing code from a past project which was a Theremin-like device and used two distance sensors to calculate hand distance similar to a real Theremin which uses radio waves. Code from this project also filtered bad data from the readings so unreliable readings would be ignored or at least translated into data usable by the servo.

Screencap of Arduino code

Project files were made public through Dropbox. These files are duplicated from the working copies and not the originals which have file names which change to match the current date. I talked about this method of dates in May of 2014 during a failed 3D printer project.

Files for Self Contained Haptic Distance Sensor:

To do:
  • Design way for servo cam to push on user without rubbing
  • Print enclosure
  • Test for usability
  • Refine design
  • Write program for Arduino
  • Test device
  • Write instructions
  • Propose project for TCP for workshop
  • Make files public

The rest of the posts for this project have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

2015-03-24 (Tu)

Monday, March 30, 2015

2015-03-29 (Su) Self Contained Haptic Distance Sensor

A list of changes to the enclosure was made which corrected the known problems with the design. The 3D modeling and rapid prototyping saved considerable time and resources by comparing sizes in reality as opposed to virtually or mathematically. Real life sizes of parts were measured with digital calipers and translated to the model. While modeling, screen captures were taken so an animation could be generated which showed the changes in a brief format.

Changes:
  1. Shrink wall thickness from 3mm to 2mm
  2. Change post shapes from pyramids to cubes
  3. Revise lid
  4. Hold servo externally
    1. Add posts
    2. Use screws to attach
  5. Shrink and move logo
  6. Shrink interior size
  7. Remove diagonal screws from ultrasonic distance sensor footprint
  8. Add post to suspend ultrasonic distance sensor
Animation of modeling changes

To do:
  • Design method of holding the enclosure together neatly
  • Design mount for servo which uses screws instead of bolts
  • Design way for servo cam to push on user without rubbing
  • Model new enclosure and lid
  • Model enclosure 
  • Print enclosure
  • Test for usability
  • Refine design
  • Program Arduino
  • Test device
  • Write instructions
  • Propose project for TCP for workshop
  • Make files public

The rest of the posts for this project have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

2015-03-23 (M)

Sunday, March 29, 2015

2015-03-28 (Sa) Twin Cities Plus

On Saturday I was part of a roundtable discussion for Twin Cities Plus, a local non-profit for which I am the secretary.


If you  skip to 20:55 that is where the meeting starts. We'd love to find people to donate time and skills. Money is also accepted and we're a nonprofit charity recognized by the IRS so donations are good for everyone. Even leaving a comment on the YouTube video page would be appreciated.

Saturday, March 28, 2015

2015-03-27 (F) Weekly Summary

The 3D Printed Automatic Tea Maker was completed. During the process I found a web service which allows me to easily put 3D models online and you can look at the models easily. Thingiverse didn't offer anything as streamlined that I could find. The biggest hurdle of the project was to create the enclosure and 3D printed parts which was still new to me. But that was the point in this project: I wanted to teach myself about 3D modeling. There was a lot of wasted space in the enclosure and the footprint for the LCD screen wasn't totally accurate but the project came together. Not only did I learn a lot about the modeling but the project worked so it was ultimately a very successful project.





The tea maker ran as well as I had hoped. The interface is easy to understand and intuitive, at least I think so. Users turn the potentiometer to the desired time, which is shown on the screen and press the start button. If the they aren't sure what time to select the screen also shows the tea name. The video below shows the operation. The files necessary for someone to copy the project have been made public. To make understanding the project easier an Instructable was made which shows step-by-step how to make a copy.


Video of tea maker operation

Files for 3D Printed Automatic Tea Maker:
// COMPLETED // COMPLETED // COMPLETED // COMPLETED // COMPLETED

A new project was started. This project was based on previous distance sensors which translated distance to pressure through a servo. The version created by me was not trying to revolutionize or do anything new but instead was meant to make the project more accessible. With a 3D printer and some soldering a user could gain sonar sense in a very small package. The largest component was a USB battery pack. If the project is successful a workshop could be arranged so the skills and device could be spread to the community.


Animation of enclosure progress





The rest of the weekly summaries have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

Friday, March 27, 2015

2015-03-26 (Th) Self Contained Haptic Distance Sensor

The first printing of the enclosure was meant as a draft copy which would require revision. Measurements were taken and parts were held up to it and laid inside to get an idea of how they could all fit together. Previous workflows without a 3D printer could not feasibly create an enclosure with the sole purpose of visualization in order to create future editions.

The ultrasonic distance sensor did not fit into the holes as designed by using internet resources. The spacing and sizes were nearly correct and the discrepancy may have been due to the printer's tolerances. The screw/bolt holes however did not match the model of distance sensor so measurements were taken and a second footprint was generated which matched the model used. The bolt holes were significantly smaller and the only size of bolt which could fit was 1.6mm which was fortunately available at a nearby hardware store. The second faceplate was printed as a thin piece which was merely meant to test the fit of the footprint. It fit well and also demonstrated the need to put a spacer between the ultrasonic transducers so the sensor would sit parallel to the plate.

Test faceplate with ultrasonic sensor

1.6mm bolts with sensor and faceplate

The servo mounting issue had not been addressed before the first enclosure had been printed. After holding the servo in different positions it was easy to see different ways of mounting it. The most efficient solution was reached after days of contemplation and involved keeping the servo entirely out of the enclosure and mounting it on posts extending from the rear cover. This will keep it opposite the direction the distance sensor faces so the components form a line. This will also shrink the enclosure size. No sketch or model has been made of this proposed shape. Measurements were taken to increase the likelihood that the next print of the device will be final. The servo horn attachment has not been tested but will not need to be reprinted unless it needs to be changed.


Measurements being taken

To do:
  • Design method of holding the enclosure together neatly
  • Design mount for servo which uses screws instead of bolts
  • Design way for servo cam to push on user without rubbing
  • Model new enclosure and lid
  • Model enclosure

The rest of the posts for this project have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

2015-03-21 (Sa)

Thursday, March 26, 2015

2015-03-25 (W) Self Contained Haptic Distance Sensor

The model was improved to include walls, a back cover, and a power cord hole which will probably be replaced with a port which will pass a coaxial power connector. The back cover was embellished with my symbol. The back cover also has four pyramidal posts which are meant to mate with the walls to ensure a tight fit. These posts may have to be moved in slightly to account for the error in printing.

All the work to the model so far has been compiled as an animation to better visualize the process. This animation was constructed by rendering images in OpenSCAD when any significant step was taken. The images were animated by importing them and exporting the layers as an animated gif. There are 300mS between each frame with a 5000mS delay on the last frame.

Animation of enclosure progress




 To do:
  • Design method of holding the enclosure together neatly
  • Design mount for servo which uses screws instead of bolts
  • Design way for servo cam to push on user without rubbing
  • Model enclosure

The rest of the posts for this project have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

2015-03-18 (W)

Wednesday, March 25, 2015

2015-03-24 (Tu) Self Contained Haptic Distance Sensor

One of the first Make Magazine projects which really caught my eye was two distance sensors hooked to two servos through a controller. The wrist-mounted device was instantly appealing because it gave wearers an innate sense of their surroundings. I am very interested in expanding human senses with technology such as the ESPeri.IRBud which gave a user information on temperature using an infrared thermometer or the magnet in my left ring finger and another one in my left index finger. The magnets allow me to sense magnetic fields like microwave ovens in the kitchen and powerful solenoids where I work.

This project aims to capture the functionality of the wrist-mounted device but make it more modular so it can be easily repurposed. This design could be applied in multiple locations along a person's arm or shoulders to give a better sense of surroundings. My goal is to make it so easy to build that people will come up with their own placements and uses.

Enough background.
----------

Modeling was done for a servo spindle which would apply varying pressure to the user depending on rotation. The hole in the middle is meant to attach to a servo horn and may need to be adjusted so that reasonable pressure is applied. Most importantly this is a cam which does not attach a disc to its center. Since the servo will rotate the piece from off center the piece will extend further and further as it spins which will apply more and more pressure. Since the pressure should be relatively low a very small servo will be used since they are inexpensive, easy to control, and small. The hole for the servo horn was copied from the 3D Printed Automatic Tea Maker project.
Messy look at servo cam
Cleaned up servo cam

A second part was started which will hold the distance sensor. The footprint was made by referencing an online diagram which showed the dimensions in millimeters of the relevant parts. The parts are being made with the same approach as the previous projects where variables are declared in the beginning of the code and changing them will allow for the project to change as necessary without breaking anything. Another technique used more was the use of the use < > command which allows code written in other projects to be utilized without having to import bulky code.
Simple plane with distance sensor footprint
Screw wings added for enclosure assembly. Taken from Tea Maker project

To do:
  • Design method of holding the enclosure together neatly
  • Model enclosure
  • Design mount for servo which uses screws instead of bolts
  • Design way for servo cam to push on user without rubbing

The rest of the posts for this project have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

2015-03-17 (Tu)