Let's Make Robots! | RobotShop


simple autonomous robot with a remote control
Using a
Recently, I volunteered at my son’s high school to be a coach/teacher for their robotics club. It turned into more of a weekly class which ran once a week for 2 … Read more

Light following robot

Hey there guys. Well I found this project here on this site and i wanted help since it doesn't work. I already tried it 4 times and yet nothing happens. Since I'm new to this, I don't really know how to read robot schematics. Maybe I did something wrong with the circuit and since I do not know how to use a transistor. Please please please help T^T

This is my first bot and made this using two ldr and arduino . Read more
Blinks when getting dark
Last Friday my little one brought back an empty Yakult bottle from the Kindergarten. The teacher said the kids should build something with it. Since we once already … Read more

Robot water level sensor idea


I spend 2 - 2.5 hours each day commuting to and from work, and I have plenty of time to think about things. 

One thing I have been thinking about is that I have never seen anyone use liquid as a way to keep a robot level.  I can't imagine that I am the only one to think of this; people must have looked into it and discarded it as a solution, or we would have three of these on our workbenches right now.  Or am I onto something really, truly original? 

Once a CD Drive, now a scanner
I created this scanner after working with it, either directly or indirectly (I mean I had to learn how to use Stepper motors, program in the Processing software, … Read more
Tells the direction of motion
The device uses 2 ldrs. It is programmed to check if any of them is low(I mean not receiving light). If so, then it checks if now the other one is low. Based on … Read more
Light Following Robot without using microcontroller. This wheeled robot does not avoid collision. It runs towards the light or just brighter areas.
The gear motor wheels, multi-directional wheel and the plastic sheet. I cut out 6 x 13 cm plastic for base. Glued the wheels to make the body and connected the … Read more

Axe - the sumobot

Hello hello!

As you can guess, I am making a new robot, and it is a small sumo!
- Picaxe 14M
- 2 modified micro servos
- 1 LDR to see the line of the ring
- Sharp IR sensor
- Bottle cap wheels until I make up a better solution (Yes, lol :D)

And when I will receive parts, or get something done, I am going to update this until it is time to post a robot!
Tomorrow (I think) I'm going to post schematics and maybe printed layout ready to make it pcb!

LDR and IC logic gate

I have a basic LDR circuit 

Looks like this one except there is no pot >>> http://www.reuk.co.uk/Light-Dependent-Resistor.htm (the 1st figure)

I have 2 of them and I want to logically or them together.. The problem is I dunno where to connect the IC i tryed connecting it to the legs of the LED and transistor but i don't get the desired output.

the truth table became like this

(the input is the LED output of the LDR circuit and not if i put the light on the LDR)

Hello! Just found out about LMR a week ago and I've learned so much already! This is a great community and a big thanks to all the people contributing to the … Read more
Displays the time in binary
Hi, this is a binary clock that I made for fun out of a Teensy 2.0, some 3mm leds, and RTC, and a 3D printed shell. It displays the current time(in 24-hour … Read more
This is a simple robot that I made for my cousin, it only uses 2 LDRs, 2 geared motors, and a 555 timer IC. I reused a Tamiya Tank tread kit and gearbox for … Read more

attiny85 h-bridge ldr robot

I have an idea for making an simple robot. Maybe solar powered... doesnt have to be...

I have an ATTiny85, an h-bridge from an arduino motorshield (L293D, I think) and some LDR sensors and some 3V-6V motors.

My question is, can I somehow put them all together to make a simple robot? If so, do I need anything else, besides simple resistors and capacitors? Or am I missing something?

Update 3-25-2012: So I used this simple code to program the ATtiny using the Arduino as ISP


void setup() {                

Follow Light Stop in front of Object
Using a
This is a light follower robot that stops in front of objects. Its made from a Microbot from Picaxe. Code:   symbol left = b9 symbol right = b7 symbol difference … Read more

Sensor seeking.

Let's Make Robots! Hello LMRians! I ordered some parts and i order more in few weeks.

I want to do my own sensor using LDR,IR led and normal leds. And yes, it's going to be something like AmandaLDR but not exactly same.

The sensor is going to my mini sumo, project what i'm working for. It's using Picaxe-08M. What do you think about it?

Value changes and Arduino.

I hope you can help me - I¨m sure it's not too complicated, I just know yet how to ask my Arduino to read it. 


So, I'm playing peek-a-boo with my robot (arduino, light sensor and a motor)

and I need to tell my arduino to read that:

If the value of the LDR (which is usually around 600) goes below 100 (for more than 2 sec) and then above 400, it should trigger the motor. 


Thanks a bunch, 

Nothing much to describe about this robot.Its a simple line follower robot which uses 2 ldrs Read more
Turns on and off whatever you connect to it
There are already some great projects on the internet about hacking home automation systems, but what I wanted to do was to control my plugs creatively. Thats why … Read more

How to keep pixace controlled robot from getting stuck?


I have built my first robot after advice of  LMR start here. So my robot is navigating with help of IR sensor and has those standard geared motors.

 I'm wondering if picaxe can read information from motors if the robot gets stuck. I guess motor makes some noise in such a situation?Can pushing against some obstacle with rubberwheels on harm picaxe?

I would be grateful for any piece of advice!




I would like to know if the PIC12F675 from microchip can control 2 LDRs, a buzzer, and a LED. I know it might sound a simple question but this is for my starting project with Microchip and C programming.

If it is possible I would appreciate if someone could tell me how to wire the components to the PIC.

Thanks, GranTotem


Navigates around via ultrasound, turns on the lights when it gets darker, looks just awful and feels raped.
Using a
First of all, hello LMR! I'm new here so very impatient to learn everything and meet everybody. I saw this website few months ago and instantly fell in love with … Read more
Changes his facial expression according to brightness
Using a
No, wrong thought --- it's not a Jack O'Lantern robot. Mr. Sunsmile changes his facial expression according to the brightness of the ambient light. A LDR is hidden … Read more
Navigates around via ultrasound without falling using LED and LDR, Follows lines.
Using a
This is my first homemade robot. It is inspired on the Start Here Robot and Amanda LDR. Changes: Read more
Lights up when it becomes dark and lets you get in bed without breaking your feet or furniture in the bedroom :D
This is my little LightBox, a night light. Basically what it does: When you switch off lights, it lights up for a minute for you to reach your bed without accidents … Read more

Peculiar ldr problem...

Hi, well got my robot to follow light, to see if everything was working fine, but the weird thing is, instead of changing direction in real time, it only changes direction when i reset my arduino board, same thing happens if i watch the serial monitor.


for example


it prints out 500 to the serial monitor

keeps printing 500, even if i change the light source.

LDR problem

Hey i plan to make a robot that has no brains at all. but the LDR's are not working! they were working in the previous appliance (outdoor light) but not now with a battery,motor and an LDR and it won't work! here is the schematic for my robot.


My Schematic                                                                        Can you please tell me what is wrong!

Slightly more advanced LDR eye

Read this history first, if you have an hour to kill.

The challenge: make your bot rove around your house. Use no active beacons. Use observations by your bot only. Now, does your bot know where it is?

One possible answer: an eye and a brain.

Room Recognition

Each room in the house has a unique lighting situation. A simple eye that looks around in eight directions would "see" a pattern of light and dark segments. Each cell is connected to one ADC on your uC.

A question about hooking up 2 LDRs to 1 picaxe input.

Hey everybody. I am a long time lurker on this site and I would like to thank you all for all the valuable information here. I have built a start here bot and a few more complex things of my own. Now I am trying to build a very small sized robot with a picaxe 08m.

I am a beginner in electronics. I know how to hook up a LDR and read the input, but I would like to know if there is a possibilty to hook up 2 to 1 input. The problem is I am short 1 input on my robot and all the other picaxe pins are in use. The 2 ldrs would be used as left and right eyes in a sense.