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Product Design of a 4 wheel differential drive robot

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Inventory App for hobbyists

I used to buy a lot of small electronics component and sometimes store it for future use. The problem is sometimes it is hard to keep track of what you have in your collection. I find it hard to find any free inventory app that does the job. There are pretty good paid software, if you want to use it for some shops/warehouse etc. So I made an app that does the job. It is build using nwjs framework. You can find the whole source code + binaries on my github page. Searching the inventory item Adding entries Modify entry Delete entry

Raspberry pi based Car Infotainment system

Out in the market, there are a handful of car infotainment systems that you can buy for 10 to 30k INR. But nothing beats the thrill of making one from scratch and put it on your own car. So this is my effort to make one from the scratch. At heart, it is a raspberry pi 3 Model B single board computer. For those who don't know about raspberry pi, it is a single board compute with a Quad Core 1.2GHz Broadcom BCM2837 64bit CPU with on board WiFi and Bluetooth. See this for a complete spec. It is connected with a 7 inch multi touch display running Ubuntu Mate (a Linux variant). Os is modified so that it is only running the bare minimum services to run the system. It will save the boot up time and improve performance a little bit. It is connected to a GPS module via UART to get current location. It is used in the navigation section. It is also used to get time, when the device is not connected to internet. It uses google map API for navigation. The complete infotainment system is

Creating a Wireless remote for Nikon Camera using Esp8266

The Nikon DSLR camera I own does have a Bluetooth connection, but unfortunately it is of no use. You cannot trigger shots from Bluetooth. Also u can only share photos of low resolution across Bluetooth. What a shame!!! I also want a time lapse option which is absent in the camera. There is a WiFi option, but have to invest a lot more money to buy the WiFi adaptor. Fortunately it has an IR interface. So I thought of creating my own triggering device (like the ML-L3) which works over WiFi so that I can remotely trigger the shutter and also take time lapse pics. I can control ESP over phone and ESP will in turn control the camera using IR. (It can also behave as a normal ML-L3 Wireless remote). I got the command sequence for taking shots from here ( http://www.bigmike.it/ircontrol/ ). This is the code I wrote for controlling my DSLR. I am able to remotely trigger the shutter from WiFi. remotely trigger the shutter from remote. configure to take time lapse pics from WiFi. (W

ROS simulating a 3 axis robot in Rviz

In this tutorial, we will create an urdf model of a 3 axis robot and simulate it in Rviz. Create a package inside your workspace (create it if u haven't any). Create a folder named urdf to store urdf models. Now create a new file called my_robot.urdf with these data. This link will give you a list of all possible tag tags and informations. (Read this before going further. link ) There are 4 links and three joints in this robot. Each joint has one parent and one child. There are different types of joints. Here we used continuous and fixed type. Joint 0 is fixed and the rest of them are continuous. The origin tag inside the <joint> <origin rpy="0 0 0" xyz="0 0 3"/> represents the amount of offset required from the parent link. This can be clearly understood from the following figure. There is also an another origin tag inside link tag. This represent the base frame of the link itself. We need to shift it by 1.5 (half of the link

Batman Key chain with ESP8266

Have recently bought a small batman key chain from amazon. It  has a small button when pressed lights the batman eye with white light and sounds a pathetic sound (:(). So I thought of opening it. It has enough space to put some custom electronics. So I thought of customising it a bit. This is what it looks before customising. This is what it looks when adding a little bit of electronics into it. It has an esp8266 with 3 SMD LED (Red, Green, Blue) that can be independently controlled. It has a small speaker (from a headset) which plays a pac man tone. It is powered with a 3.7 V Lipo battery with an option to charge with an USB cable. Batman keychain is playing pacman tone... :) I know it's a bit wierd, but couldnt find a good tone (which can be expressed as a piano tone like C4, B#2, ...) for batman. Will replace it once found a better one. Things to add further Pressing for a long time will enable a hotspot Option to change the tone by writing it to

MAV with two propeller

In order to counter the rotating torque from the previous single rotor version, one more propeller is added. The second propeller rotates counter clockwise and both torques will cancel each other (Only if both propellers are rotating at same speed). This the video of it flying with restriction. I have attached a a small weight to its bottom. Even though the counter torque is cancelled, it can't be controlled. Very small variation in alignment will drive the MAV crazy. This is an attempt to control the drone remotely with a joystick. Had changed the body from plastic (from plastic IC tube) to general purpose PCB board. The individual propellers are controlled from a joystick (logitech f710). The controller is an esp8266 es-11 WiFi chip. The telemetry data are send using a python program that run on my computer. Both the WiFi chip and my computer are on the same network.