Let's Make Robots!

Automatic plant watering system with picaxe

I designing a automatic plant watering system

.A probe is placed in grow bag.It finds the resistance

If the resistance high ( >200 with 1 k conected ) then high 0 and a relay works

It works resistance up to 100 ohm then stops


Low power radios

I would like to start a discussion revelent to low power (cost) radios and embedded electronics such as robots, environment sensing, and remote control of household or shop equipment. I am NOT an RF engineer.

To date I have experimented with:

  1. Raw, very cheap, tx or rx modules and transceivers
  2. NRF24L01 transceivers
  3. Hope RTM69 transceivers
  4. ESP8266 Wifi modules

I also have some other WIFI boards (Digilent PmodWiFi) that are still untouched.

Again, antenna and RF design are NOT part of my skill set!!!!

Help to buy a Mobile Robot

Hi all

I need help to guide me to buy a two wheel mobile robot with components (for example encoders , compass,others ) that make me know the robot position (i.e. X , Y , and Orientation ) precisely in global map . so which robot platform is good for that ?

Hint : I need this robot to implement Artificial Potential Field algorithm .


Support PopPet


Looks like dx, banggood and tindie all pulled this from their 'shelves'. Banggood wants to know who can supply PopPet. I'm passing them CP's way.

I'm scrubbing this post to avoid giving anyone bad names at this point. Thanks everyone.

Hello Guys & Gals,

I am posting this so that fellow LMR members know what is going on, and send an E-mail to ____ in support of PopPet.

Black Friday: 15% OFF Coupon Code Plus Lucky Draw‏

The biggest retail weekend of the year is right around the corner. Enjoy the 15% Off coupon code and Lucky Draw now.

Go to the deals: http://www.icstation.com/newsletter/eMarketing/IC_BF14.html

Excel ... Tip

Hi all just thought i would post this which could be handy for those who use Excel .... as i have seen post where people work out things for there robot projects in excel.

Requesting help: How to identifying a battery connector


I'm currently in the process of up grading the batteries for my current robot project to use 18650 Li-on batteries. However, the battery holder for the  4 x 18650 does not have a conector such as the one on the alkaline battery holder.

Can someone help me identify the connector?

I'm not sure if the connector is a Fut J, JST, BEC, etc.

Thanks in advance. 

Large robot chassis with 50W MP3 player

Dagu is now selling the chassis for our Venus robot as a separate product for $435 USD.
Please note there is a discount for people who log in and an additional discount for LMR members.

This is an ideal chassis for anyone who wants to make a large butler robot. It is an aluminium chassis with 2x 200mm (8 inch) drive wheels with rubber tires plus 4x caster wheels for stability.

Verbal Skills and NLP

I'm starting this forum for discussing verbal skills in robots including but not limited to natural language processing.  I'd like this to be a place to discuss conventional and out of the box ideas for improving verbal skills in robots.  This could involve:

Christmas Specials for LMR members at DAGU

Now is your chance to grab a bargin from DAGU. From now until the end of December DAGU is offering discounts for all LMR members.

Go to our website: http://www.dagurobot.com to find what you want and then contact Mr. Lee at DAGU. Tell him you are an LMR member to get discount prices.

Ideal Battery for the T'Rex Motor Controller and Wild Thumper 6WD Chassis

Hello LMR Rockstars!

What's the best battery to use with the T'Rex Motor Controller and Wild Thumper 6WD Chassis? I'd like as much speed, torque, and runtime as I can safely get. I've been using a 3S (11.1V) 30C 2650mAh. Could I go up to a 4S (14.8V)?

Robotix 2015!!!! @IIT KHARAGPUR

Technology Robotix Society is proud to present ROBOTIX 2015, its annual technological extravaganza, to be held during 30th January – 2nd February,2015 as a part of Kshitij, the annual Techno-Management Fest of IIT Kharagpur.

How to make a robot look steampunk?

Dear: LMR

Hello this is me Noah. You should know I am trying to build a steampunk robot chassis. This robot is going to be made of cardboard, arduino uno, and other materials. What I am trying to ask you is this how do you make something look steampunk, what materials do you use to make something look steampunk, and how to design a steampunk texture for my robot? I could use all the help I can get so thank you. By the way this is what I have done so far.

From: Noah 

Simplified occupancy grid mapping

I have a setup, where a distance sensor, such as sonar or IR, rotates about 180 degrees and takes a distance measurement every few degrees. What I would like to do is to create a occupancy grid out of these measurements on an Arduino or, more specifically, I would like to compare two different algorithms, which create the grids.
One of these algorithms would be made by myself, but in order to make a solid comparison, I would like the other algorithm to be the one which is mentioned in occupancy grid materials and research papers, which utilizes a binary Bayes filter.

Wearhouse Arc- Wireless headphones reinvented

I will tell you a little story about Nelson, our hackerspace member here in Shanghai. Xinchejian, the Shanghai hackerspace is quite a breeding station for new engineers. Nelson did prototype a new kind of headphones which enables you to share your music with many others via Bluetooth and an App. Control play/pause, volume, next song etc. via a touch sensitive surface on the right earcup. But I will shut up now.

Disassembling RC Car for Chassis

Hello, I am putting together a quick robot, and I figured I could skip a couple of steps by purchasing a remote controlled car, taking the frame off, and using the chassis as a preassembled remote controllde base.


Has anyone does this before and has any tips? What cars are good for this, and do any specifically have better chassises? Thanks!

How to affect a variable timer in lbink ?


I tried to make the first example blink, everything seems very easy till I tried to give a value in the green field ? How to find this green field ?

I didn't find it in tutorials



For unni

Think you will want something like this for code on 28x1 from our brief shoutbox conversation, you will have to pick the value from your sensor, I used 5 as example. This is using adc pin 1, and pin B.1 to go high and turn  on your relay. Have no idea if this works or what you have for sensor, also you might need to turn relay on with a transitor depending on current draw. Please remember picaxe does not like over 5 volts.

;for unni