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Iterative Design Summary

The body of the pill dispenser went thoguh several versions. First it was designed on Fusion360, then it was rebuilt in SOLIDWORKS. The screw footprints were tested on the laser cutter to make sure that they could accomodate the motors. Finally, the form of the body went though several revisions before landing on the presentation version that completely enclosed the infrared light sensor in the hopper body.

The control unit also went thoguh several designs. Those shown below are not even including the models that were made very early in the class. At first, I wanted to have a contorl unit that was all curves, but this didnt work for two reasons: 1) a continuous side panel was too long for my laser and 2) the small curves were too short of a radius for the wood. Also, it is worth noting that there is no good system for making the tabs along curves in standard SOLIDWORKS, so I just did the geometry to make it work. (These angles could still use a bit of adjusting -- in the end, I cheated with wood glue). I ended up with 4 side panels and they mated together nicely.

The central hub for the serial connections went through a few versions. There was a hub that just connected things to an FTDI cable (not shown) and then the first one shown here had pigtails so that I could connect to a satshakit. In the end, I decided to integrate an Arduino Pro Mini and made a footprint to solder it in to the hub. This worked well for the presentation version, but I would like to move to a more integrated ATmega328p chip driven board, possibly with the periferals integrated.

All of the electronics went though several revisions before the presentation version (and I am still working on them after). The examples here are all motor driver boards. The leftmost image is the DC motor, that worked but was ultimately swapped out for another unipolar stepper motor. The following boards were for a bipolar stepper and then three iterative versions for the small unipolar steppers that made it into the presentation version. Ultimately the rightmost version should be the only used, but I had to make a last-minute swap out at the last minute for one version prior when a board burnt out.

The agitator and queue depicted below went through several versions as well. These changed, with a measurement of the pills, change of the motors and further fine tuning to better fit the hopper and queue housings.

You can see all images (used and unused) from the final project's work HERE.

The final presentation of this project for Fab Academy 2017

Build Instructions

The pill dispenser is a simple device that is still actively under development. Not only can it be highly useful for the individual user, with a single type of pill, but work is being done to simplify the design's construction, improve reliabiliy and better the extensibiliy. A planned future internet connection will also be able to send reminders and information to health information systems.

Contact Corey Rice (LinkedIn) for more information on this project, its use, or recent updates. All files needed to build the device are below, including the bill of materials. All of the files included here are restricted to the most up-to-date versions, as of the presentation. The messy and imperfect files that include all of the design files that I iterated beyond, are available via Dropbox. Any further updates will always be available here: github.com/crice009/PillDispenser.FabAcademy2017-beta

• 3D printable parts
• Laser cuttable parts
• Millable circuit files
• Code for all boards
• Bill of Materials

The first and foremost step would be 3D print all of the printable parts. Rather, you may want to start this first, since they are particularly long prints. The two largest parts each took nine hours for me at 30% infill. Once the parts are built, you can proceed by attaching the motors, queue and agitator.

An assembly item that needs to be carefully noted is the insertion of the infrared light sensor. The code for for this is still currently under development, but the hardware is available in the current design. The smaller board that has only two resistor, the IR LED and the IR phototransistor is inserted into the hopper, after being threaded through the queue base. this is complex to show or describe, but will likely make sense once all of the parts are together. The images below show this froma previous version of the hopper, where the board is more visible.

Once the Infrared sensor is threaded through the hopper and base, the queue can be confirmed in place and the entire assembly can be secured with M4 screws and captured nuts. The unit should look as it does in the images below. Now you should laser cut the console housing, so that it can be assembled and mated to the 3D printed parts. It is important to note that the only exposed wire in the whole unit (in the presentation version) will be able to submserge back out of view through a slot in the console housing as shown here. The 3D printed assembly will just sit over top of the console, mating to the laser cut parts. (This design choice was because the console will ultimately be extensible, to accept multiple hopper assemblies.)

If you have not already, mill out the reamining circuit boards and populate them. compile and upload all code, using the AVR-libc and Arduino toolchains, respectively. You will also likely need a FABISP, Arduino as ISP, and FTDI adaptor/ cable to upload this code to each board. I wholeheartedly recommend testing each of the parts before integrating the system. Also, the 2.1mm barrel Jack will likely have a small post you need to cut off before it can be soldered.

Once the electronics are assembled, you should connect the nodes to the hub connector. There will be a three node bus started from the hub connection closest to the speaker. This chain will be for both steppers and the IR sensor. The keypad and LCD each get their own serial connection. The LCD is connected closest to the barrel Jack connector, and the keypad is connected adjacent to that. The spare connection is where I had planned to include an ESP8266, but never had time. PLace all of the electronics into the console housign, making sure not to stress any of the wires, or cause any short circuits. Use the standaoffs and hotglue as needed to hold things in place or insulate contacts. Future development on the electronics is aimed at reducing the number of processors in the system, and simplifying the serial connections. For now, it is critically important that all electrical bus connections are in the proper orientation, so that power is never applied in the wrong way to any of the boards. Not all of the presentation versions of the boards have diodes present everywhere needed for protection in case of an inverted plug.

SUCCESS!!! If you have followed these instructions and used your intuition (or emailed me) to fill in the gaps, you have now successfully assembled your very own pill dispenser. I will be continuing to develop this project further, so check the link above to see how things have progressed since June 21, 2017. Hopefully I will have made progress integrating this device, putting it on the web and, perhaps, even integrating it into helthcare providers' datastreams. If so, I would be happy to help you connect your pill dispenser into that service network, so you can reap the full benefits.

Enjoy and be well. -- Corey Rice 2017