Category: charging

Basic Node for the Internet of Sex Toys (part 1)

March 23, 2017 in assembling, charging, DIY, esp8266, how-to, internet of dongs, internet of things, IOT, molding, motor driver, NodeMCU, review, sextech, tutorial, vibration motor, Wemos mini, wireless charging

Wemos mini modules: ESP8266, motor driver and battery charging (in the middle); Wireless charging module (right side); wireless charging coil (top side); encapsulated vibration motors (left side)

In previous posts we showed how to build a vibrating sex toy in principle as part of the Internet of Things (IOT). In addition we have selected a hardware platform – the popular ESP8266 – for controlling a vibrator motor, gathering motion data and connecting to the internet. Now we want to build the toy itself.

part 1: Basic Node for the Internet of Sex Toys

part 2: Molding the Basic Node

part 3: Software for the Basic Node

Brief Review of development boards

There are a lot of development boards which are equipped with the ESP8266. The popular NodeMCU was already introduced here. Here is a quick overview and comparison:

NodeMCU

plus: very popular, cheap, USB connector for programming
minus: quite large (for being part of a sex toy), no support for battery charging

Adafruit Feather Huzaah ESP

plus: USB connector for programming and battery charging, smart form factor (only 23 mm wide), very good support (libraries, tutorials)
minus: quite expensive

WeMos D1 mini (pro)

plus: very cheap, USB connector for programming, additional stackable modules (eg. battery charging, TFT screens, motor driver), good form factor
minus: no real support (but there is a forum, problems with modules reported

ESP8285 (variant of the ESP8266)

plus: really small (!!!) and smart form factor, USB programming and battery charging, optional sensors on board (but no motion sensors)
minus: quite expensive, only 1MB memory (nevertheless enough for a lot of application)

For our project we selected the WeMos mini cause we get almost everything we need:

USB connector for programming
module for battery charging
module for a motor driver
good form factor (eg. to be put in a vibrator handle or in the base of a dildo)
cheap, fast delivery

But there is no shield for motion detection (accelerometer,gyroscope). So we have to use an additional board eg equipped with the MPU9250.

But there is a problem with the WeMos motor shield: After a few seconds it stopped working. And in addition the MPU9250 stopped working, too. Hours and hours we tried different configurations, changed the libraries … The problem was the motor driver shield itself. Fortunately there is an easy work around. Read here.

Another issue is the battery shield. It has an extra USB connector for charging the battery. So you have two USB connectors (one for battery charging and one for uploading). Two USB connectors are not handy. Fortunately we can do without the USB connector for uploading as it is possible to update the software over the air (OTA) using WiFi.

Material

As the body interaction philosophy uses motion for controlling the device we have to add the MPU. Again we use the MPU9250 which has an accelerometer, gyroscope and magnetometer.

Another insight was that you need at least a switch for rebooting. As we want to mold everything the switch must meet the IP67 requirements, which means it is water- (and silicone) proof. If you don’t want to mold the electronics you can use the RESET button on the WeMos mini board.

A perfect basic node has a wireless charging option, too.

Material list for the basic node:

Wemos mini board
Wemos motor driver shield
Wemos battery shield
Wemos prototyping board
Wemos set of pins
LiPo battery (eg. 3,7V 650mAh, 2C, JST plug, available at ebay)
MPU 9250 board (for motion control)
1 or 2 encapsulated vibration motors, 3V, available at Alibabaexpress
Optional: Switch IP 67 protected (eg. Cherry Switches DC1C-K8AA IP67) – for molding
Optional: Wireless charging receiver 5V eg from Seeed Studio

Material: battery shield, Wemos mini ESP8266, motor shield, MCU9250 (first row), LiPo battery, switch, vibration motor (second row)

Soldering the basic node

We use one connector (part of the Wemos set of pins) to connect the Wemos mini with the battery shield and the motor shield. This is done to save space. If your application has enough space you would use one connector for every shield.

Battery shield, Wemos mini ESP 8266, motor shield (from top to bottom)

Now have a look at the bottom side where the motor shield should be. We can connect up to 2 motors. Solder motor 1 to A1 and A2. Motor 2 has to be soldered to B1 and B2. In addition we need input power for the motor. We just use the 5V provided by the Wemos mini battery shield. Connect 5V to VM and GND (from the pins) and GND. But you could use other (more powerful) power sources, too.

Wemos offers a prototyping board. We use it for mounting the switch and for the MPU9250. Connect the MPU9250 to the bottom side of the prototyping board. Therefore 4 pins have to be soldered

Solder pin (1 row, 4 pins) on the top side next to TX, RX, D1, D2

Now look at the bottom side of the prototyping board. Put the MPU 9250 so that VCC, GND, SDA, SCL are connected to the pins.

Next, solder the MPU 9250.

Then add more pins to the prototyping board at both sides. The picture shows the bottom side of the prototyping board.

Now wire the prototyping board. The picture shows the top side.

Now you can add the switch. Place it in the middle of the board on the top side. Connect GND and RST to the switch. Now you have a switch for rebooting which can be molded.

Now we have both parts ready and can stack them together.

Stack them together!

Now add the LiPo battery, which should have a JST header. Now your basic node is ready.

Wireless charging option

Especially for sex toys a wireless charging option is reasonable as this is a requirement for silicone molding of the toy. And when the toy is molded it is safe and washable.

The wireless charging module consists of a sender (or transmitter module) and a receiver module. You have to solder the receiver module to the battery shield. Don’t mix the modules.

unfortunately there is only a USB connector. If you don’t want to remove the USB connector you can solder the red (+) wire to the R330 resistor as shown on the pictures. The black (-) wire can be soldered to any pin labeled (GND).

Now put the receiver module on top of the battery module.

Now stack the protoytping board on top of the battery shield. And connect the battery.To charge the battery connect the sender (or transmitter) module to 5V. To power the sender module you may use a USB port power source which has about 500mAh or more. Place sender and receiver coil about each other. For a more professional charging solution you need a charging station. The making of a charging station using 3d printing is described here.

Learn how to construct the mold form in part 2:

part 2: Molding the basic node

part 3: Software for the basic node

New vibrator design “fusion”

April 21, 2016 in 3d printing, Arduino, assembling, case design, charging, how-to, molding, sextech, tutorial, vibrator, vibrator design

bodyinteraction designed a lot of vibrating toys, some are usable as massage devices, some are explicit sex toys (vibrator ring, balls), some are experimental (collar). Everyone is motion controlled. If you have more than one they will influence each other remotely, eg. a vibrator and a vibrator ring.

But a device like a classic big vibrator is still missing. So we designed the “fusion” which is approx 19cm long and up to 4+cm in diameter. It is called fusion as the case is made of silicone and 3d printed material (ABS).

We have put the body interaction vibrator development board, motor and battery in a silicone form. There is an on/off switch – so when you travel the vibrator doesn’t wake up when it is moved. And you can charge the battery with a USB micro connector. There is a spacious inlay for the electronics, so it will be easy to get it done.

Pros:

easy to charge the battery via USB
on/off switch
hard handle
flexible upper part
large (if you like this)
ISP interface (“hacker port”) accessible

Cons:

only the silicone part of the form can be put under water for cleaning

What do you need?

200 ml silicone with high shore A rate, eg. shore A 45 from silikonfabrik.de
optional: special colour for silicone molding
3d print of the molding form, inlay and closure
tinker wire
body interaction vibrator development board with LiPo and motor (or similar Arduino boards)
bin for preparing the silicone, something to stir the silicone

How much is it?

Board, battery, motor: 30$ (buy at Tindie)
Silicone: 10$
3d Prints: less than 5$

Step by step instructions

Step 1: Print out the inlay, the form and the enclosure

Download as zip-file: Fusion

Download at Thingiverse: http://www.thingiverse.com/thing:1505539

Step 2: Prepare the inlay: Insert the body interaction board and the LiPo battery

The body interaction vibrator development board is inserted into the provided rails. It it doesn’t fit in use a file to remove printing artefacts. Use some glue to fix the board. Then insert the battery and fix it.

Important: The Micro USB connector must be above the upper part of the inlay.

Step 3: fix the wires of the vibration motor

The vibration motor will hang down from the inlay as the inlay will be put in the form upside down. You can influence the position of the motor by shortening the wire or fixing the wire to e.g. to the battery. In this case the wire of the motor was threaded between battery and board. Therefore the motor will be in the middle of the vibrator.

in the center there is the overmolded vibration motor

Step 5: Prepare the form

Use some tinker wire to “press” both parts of the form tight together. molding-form-empty Use some wax to fix little holes in the form where the printer failed. (These are the white spots)

Step 6: Insert inlay into the form

There must be some space between inlay and form for the silicone.

Remark: The two wedge like forms at both sides of the inlay help to hold the inlay. The wedge can be removed after molding. inlay-in-molding-form

Step 7: Cast the silicone

Prepare the silicone as the producer recommends. It takes some time to pour the large amount of silicone into the narrow form. The silicone we use must be used within 10 minutes. So start at once after preparing the silicone.

Important: The USB micro connector, the switch and the ISP connector shouldn’t be dashed with silicone. If this happens remove the silicone. Maybe some silicone will remain behind. This can be removed later when the silicone is solid. molded

The battery is covered with silicone, the USB connecor and switch are not. drying-seen-from-top

Step 8: Remove the form

Remove the tinker wire. Remove overhanging part of the silicone. Carefully tear both parts of the form away. You can use a knife, but be careful not to “hurt” the vibrator. Remove overhanging silicone at the vibrator. Also remove the two wedge like forms at both sides of the inlay.

Step 9: Install the closure

Now you can put the closure on the inlay. Fix the closure with glue. (Be careful! The USB connector is not very strong.) closed-inlay

Tinker, share and download from Tinkercad:

form and inlay: https://tinkercad.com/things/b8nQxRn4XWl

closure: https://tinkercad.com/things/dhgtgeaYG0B

Download as zip-file: Fusion

Download at Thingiverse:

http://www.thingiverse.com/thing:1505539

USB powered charging station for the silicone molded vibrator

April 14, 2016 in 3d printing, Arduino, case design, charging, how-to, sextech

We made a DIY silicone molded vibrator (see here, here and here) using the Arduino compatible body interaction vibrator development board and a wireless charging module. Now we need a charging station where you can put your vibrator for battery charging.

We need a simple box for the wireless charging sender (transmitter) module and the coil. In addition we need a USB cable which we will cut though and connect to the charging module.

It is important to keep the distance between sender and receiver coil as small as possible. The larger the distance is the less power will be transmitted. Therefore the plate where you put the vibrator must be very thin. There are different modules available.

What do you need?

A USB cable
Wireless charging sender (transmitter) eg. from Seeed Studio, 5V input. The sender (transmitter) will be placed in the charging station. The receiver module will be part of the vibrator. There are different modules available. Look for a 5V input module.

Instructions:

A. Print out part A and B. Download STL files (zip file)

B. Cut a USB cable. Plug the cable through the hole of form B.

C. Now connect the USB wires with the sender module. Solder the red wire to the (+) pad on the wireless charging sender. Solder the black wire to the (-) pad.

D. Glue the sender board on the bottom of the red form. Put some glue on the cable to fix it. We used hot glue.

E. Now glue the black form and the sender coil together. We used simple “UHU”-like glue. If the distance between coil and form is too large the charging could be rather slow. So don’t use too much glue.