Add WiFi to your Neato BotVac for 3$

[yadur]

Hi All,

I really love by BotVac 85, but when I'm on holidays its cleaning schedule often clashes with my other activities so I have to get up and stop it manually. Furthermore, often when I then leave the house I forget to start it again. To solve those problems (and because I like tinkering) I wanted to add a remote control capability to the bot.

The USB port looked promising, but it also has a host of issues, like the USB overhead, space constraints and last but not least cost. I traced out the regular, non-USB, serial lines on the board and identified usable contact points as well as a good tap for power.

I'm using an ESP8266 board, as they are cheap (2.50$ to 3$) and easy to program (like an Arduino, but with built-in WiFi). I developed a simple software that acts as a serial <-> websocket bridge. It also has a (very primitive) web interface.

If you're interested, you can grab the software and the instructions here: https://github.com/sstadlberger/botvac-wifi



The basic steps are:

1. Copy the software to the ESP8266 board
2. Connect four wires between the bot and the wifi board
3. Close everything up and have fun

BR,
Stefan

[JEfromCanada]

I'll wait for the engineers on this board to try it out first.

[glnc222]

The ESP8266 is a WiFi interface module for use with a microcontroller such as Arduino or PIC (for USB interface to Neato), though is not an official Arduino "shield" attachment. In the U.S. at Sparkfun hobby supply https://www.sparkfun.com/products/13678 with a support community. Special situation is 3.3v operation for which an adapter is available for connection to 5v logic parts https://www.sparkfun.com/products/12009
As usual, less expensive direct from China. For lower power consumption micrcomputers moved to 3v levels some years ago while many logic components still work at 5v, such as sensors in the Neato robot.

For other WiFi experiments on Neato see Mods & Repairs list top of main forum page.

[RoboCup]

That doesn't sound too terribly hard. Thank you for the instructions. May be one day in the future I'll actually get around to doing this.

[glnc222]

Connections to the Botvac circuit board is not presented in detail. The Botvac USB connector is under the dust bin where ordinary plugs cannot fit with the bin installed. There is no schematic of the system board locating power supply, either, so any of these details would be useful to anyone else seeking to make this WiFi addition.

[yadur]

The ESP8266 is not only a WiFi interface module, it can be also used as a standalone microcontroller. It is well suited for this application because both the ESP8266 and the BotVac electronics operate on 3.3 volts.

I prefer it over e.g. the Arduino Uno because it is cheaper, has more RAM (2KB vs. 82KB), more flash storage (32Kb vs. 4MB) and has a beefier processor. And of course there is the built-in WiFi and smaller form factor.

(Be careful if you want to interface the BotVac with an Arduino as the Arduino operates on 5 volts. You need a logic level shifter for that. Here's an interesting article discussing the pros and cons of the different approaches: http://jamesreubenknowles.com/level-shi ... ments-1741)

Here's a detailed view of the connections. The connector on the BotVac is on the front corner of the mainboard. I hope this helps.

[LazyRoomba]

Your effectively connecting a serial device directly to the USB. As long as it's wired correctly, this will not harm the robot.

Also, a typical Arduino does draw quite a bit of power (My nano draws around 200 mAh). Benefits of an Arduino tho, opens opportunity for further modding (Like better bin full detection ect..)

Good mod, tho.

[yadur]

Just to be clear, there is no USB involved. This is a direct serial connection between two microcontrollers, where one microcontroller includes WiFi capability. I went this way to avoid the USB driver, operation system, etc. headaches.

The ESP-12F module I'm using in my VacBot only draws between 80 and 100 amps (other modules may vary).

By the way, there is a cutout for the connector in the bot so that when you remove the front bumper you have direct access to it. I somebody would find a matching connector, there would be no soldering involved. I guess that the connector would be similar to a PCI-type, but just with six pins.

Also again, be careful if you're experimenting with an Arduino. These us 5v signal levels and may damage your 3.3v BotVac board (ESP8266 also use 3.3v).

[glnc222]

Connect four wires between the bot and the wifi board

Where on the Bot? It is not shown in the detail needed. There is no documented serial port on the Botvac, so you made a discovery. There also has to be Botvac software reading this port, compared to the USB interface. This once existed in the older XV system boards but discontinued in the newer ones. The Botvac has yet another OS.

[LazyRoomba]

You can connect a serial device directly the CPU, like a UART device. I do it on my 3D printer when I killed the USB chip.

I connected my Uart on my 3D printer onto the circuit just after the USB chipset, and a DTR to the CPU reset. As long as the CPU is listening to the serial ports for commands, this can be done on most chips.

[glnc222]

If the USB port IC connects to a serial input on the CPU there could be USB protocol software for the CPU, unlike simple serial com, RS232 etc. -- packets and what not. You might think the interface must be driven by USB software in the sending device whatever the electrical connection. It is all a bit sketchy for anyone not a communications engineer.

[LazyRoomba]

The USB chip as far as I'm aware is used to identify the device so the machine its connected to can install the correct driver, control the data flow going to the CPU's serial port and reset the CPU when new firmware is to be flashed. The connection can be tapped onto another device (In this case, WiFi) and packets can be sent into the CPU serial port.

An Arduino is a good, basic, example of this.

[yadur]

Where on the Bot? It is not shown in the detail needed.

I'm sorry if I wasn't clear enough. If you look at the top outside corner of the mainboard, there is a slot cut into the board that forms an connector (labeled P7 on the top side and P25 on the bottom side):

If you just remove the front bumper you can also access it through a hole in the front:

My connector had already some (light) scratches on it when I first opened it up, so I guess it is used during manufacturing or factory testing.

[glnc222]

Nice discovery. Maybe how WiFi was added to the Connected model, planned from the beginning of the series.

[shirgal]

Nice discovery. Maybe how WiFi was added to the Connected model, planned from the beginning of the series.

The connected model use special IC on board as U27 just near to the serial port Yadur discovered.



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[glnc222]

On software: on XV there was a software demand to disconnect com when the cleaning cycle is started -- to remove restraining com cables -- but you could reconnect after starting. It may require some programming of the receiver to control the relevant signals over WiFi. Whether Botvac code the same will have to be seen.

[shirgal]

Yadur- well done with this Wifi mod project !!!
I am going to try it as soon the ESP8266 board will arrived on hand.

[shirgal]

The serial plug called "Card Edge Connector"
Hence can't find 2 x 3 row pin to match this.

[glnc222]

Card Edge Connector
As shown in the picture above an empty part of the system board extends beyond the connection traces to the board edge. A longer connector with extra unused positions is needed to fit around the corner of the board. A 2-row (double sided board) type is needed. The spacing distance Pitch is needed to specify the correct part -- many sizes made. Check Digi-Key industrial supply, Card Edge Connectors.
Worst case a longer connector can be cut down to fit.
[edit] I suspect the plug would be 10 position 2 row (sides of board, 5 each side, to reach the corner of the board),
0.1 in. spacing pitch (same as IC pins). Gold for data signals. Not common so probably only from parts distributors e.g. Digi-Key. Neato board must be checked for spacing etc.
http://www.digikey.com/product-detail/en/cw-industries/CWR-170-10-0000/CCE10G-ND/59362

[edit] For opening the Botvac case see links in Mods & Repairs list top of main forum page.

[yadur]

I did some Photoshop measuring and a quick mock-up and it looks like your guess is correct:

It looks like an 0.1" pitch based on the 4mmx4mm WQFN package size of the DRV8800 motor driver (U25).

I also extended the connector to the board edge and a 2x5 connector might fit (but not without removing the case):

I don't think that the connections on the board will tolerate many plugging and unplugging cycles as my connections were already pretty badly scratched from factory testing.