Controlling the Air Swimming Shark with your Brainwaves How does it work? Nick Carter 7/25/2016 ?????????????????????

The Idea In researching EEG Sensors I found Open EEG and their application idea. http://eeghacker.blogspot.com/2015/03/brain-controlled-shark-attack.html http://spectrum.ieee.org/geek-life/hands-on/openbci-control-an-air-shark-with-your-mind I wanted to do it on the cheap thus, MindFlex Game has 1 or 2 EEG sensor inputs.

Shark being driven at Nova Labs EEG Headset MindFlex Game RF IR Shark Remote Arduino For Video see: https://drive.google.com/file/d/0B_8yqnVcbS5gQ0ZWVjVQdGU2SzQ/view?usp=drivesdk

Block Diagram - Project Building Blocks Program in Arduino to translate MindFlex signals to Shark Remote signals Circuit* to make MindFlex compatible with Arduino Circuit* to make Shark Remote buttons compatible with Arduino Shark Remote Modified to get button signals MindFlex Toy Player Brain Control Signals. 1 EEG Sensor ?? ?? ?? ??

Interface Mindflex to Arduino - 1 What signals are available Motor control Physically moves Seems to have speed/position feedback Physical access? LED control Easy access 3 intensities already decoded 2 player access Other Hack controller? More difficult – little info available I chose the LED control

Interface Mindflex to Arduino - 2 Interface to LEDs – how do I monitor them What is the drive LED signal Light intensity varies with Pulse Width Modulated (PWM) signal How do I interface to it, Arduino has Analog and Digital inputs. Digital interfacing requires careful timing and there are 6 lights. Analog interfacing is easy. I used an RC network to convert PWM to analog. Use threshold values in the Arduino to decide if LEDs are “ON/OFF” for control purposes

Wiring inside MindFlex Base Unit LEDs LEDs Connectors LED Wiring to Connectors LED Wiring to Connectors

Arduino Code Major Code Blocks – Loop this Read Analog Inputs Compare Analog inputs with thresholds to see if they represent ON or OFF. Since the filtered signal is a saw tooth, we need a big hysteresis. (Difference between thresholds more than saw tooth height.) Decide Shark Drive action based on LED ON/OFF Forward, Turn Left, Turn Right, Up, Down Send signals to “push” the Remote Control buttons Turn solid state relays ON/OFF with Digital outputs Create Sequences for Drive actions as callable functions Forward = side to side tail wag, alternate L/R button press Turn Left = Short wag R, Long wag L. (Turn R = opposite) Up/Down – requires 2nd player, use manual control at first Using one player, Activate Drive sequence Forward when Green LED is on, Activate turn Left or Right when Orange LED is on, Change turn direction every time Orange is achieved after Green. Notes: 2 Player LED signal sets are available – players would have to coordinate but more control information is available. Preprogrammed Shark drive sequences could be used without the “mind control.” just using the Arduino – or using other input means.

Interface Arduino to Shark Remote control Remote control has push buttons to control the Shark. 3 buttons close to a common signal 1 button does not** I need to wire out the button contact points I will wire to a convenient external connector for my relay board **This was my remote version. Some versions of remote may have all buttons with common connection to switches drivable from Arduino, but relay drive is universal. Ribbon cable with 6 pin connector to Relay Board

Interface Arduino to Shark Remote control Solid State Relay I need to close the Push Button circuit from Arduino I cannot drive directly from digital outputs for all I need a relay (isolated contact) for the 1 contact I designed a quad Solid State Relay board using Eagle CAD, PCB from OSHPark. Components from Digikey. Ribbon Cable Connector mate

Integrating the Parts Couple everything with connectors Breadboard interface Arduino to Game Arduino Monitor on PC. Values sent back 1=LED_ON, 0=LED_OFF Arduino Analog level REMOTE GONDOLA IR Wagging the tail from the PC (This pic shows EV3 remote not shark remote)

The Shark I used “Air Swimming Shark” from Internet. (Other fish types available) Price range $15 to $50 Requires about $15 of helium to inflate I bought a party balloon kit for $25 with helium canister. So far it did 1 full inflate + 1 top-up – more left still. Shark stays inflated a few days then may need to be topped up. Cannot assemble shark until inflated. 2 people needed for best assembly. Fins and control electronics are held with double sided sticky tape + overlay reinforcements. (Tricky with one person) Neutral buoyance is achieved using clay/putty (supplied). I found I had to tape some to front of shark to balance it. Normal leveling is supposed to be achieved using “climb/dive “ attitude adjustment using the remote to move the electronics module (gondola) to front or rear with rack /pinion gearing. Propulsion forwards is by side to side tail wags using remote to wag left and right alternately (separate buttons) Turn is done using the wag buttons to wag more one way than the other, or holding button down will only wag to one side.

Issues Shark fin reinforcement tape is light and sticks to itself easily. Can be difficult to apply. My placement of the control gondola using lowest altitude placement was not far enough forward to enable proper climb dive control (I added more clay taped to front of shark.) You can’t tell until you stick it on then it is too late. The fins came off in my car driving 7 miles and the shark was stressed against roof etc.. They could be re-stuck but for how long? The control gondola did not stick well to underside, curvature did not match shark. One end broke and I had to hot-glue it. The tail drive mechanism frequently became stuck and had to be manually released (forced) to continue wagging. From time to time it gets “directionally challenged” and needs manual intervention to put it back on course (see video) BUT…..despite these issues, it is a fun toy and people really like it 