MACHINE BUILIDING-

Scrapbot- Automated Dust Collector(Made using scrap materials)

Team

Daniel Jeevan

Muhammed Athif K

Arsheena E P

Riyas P K

Nizamudin K Y

For our machine building group project we shuttled across a few ideas during the branstorming session.



First idea was to build mini an electric wheelchair which could be used by handicapped children, specifically for children with no legs.The sitting platform will be only be slightly above ground, thus making it easy for handicapped people to get on it. The project was divided amongst the us:
->Riyas and Athif- Mechanical Design and parts assembling.
->Arsheena- Electronics
->Nizamudin K Y- Programming
->Daniel- Documentation & Project overseer

PROGRESS

the initial designing and construction of the project went smoothly. Athi created a deign for the body, whch only slightly elevated from the ground level.This would enable the handicapped person to easily get on the chair.The 3D design was created using Autocad.



The shaft system and placement of the motor and the electronics components will be on the base protruding on the back of the machine.We had decided to keep the overall cost of the machine building as short as possible. towards this end, we decided to use waste/reusable materials and parts.
The body was made using the plywood we had left over from the shopbot week. The body was designed in press-fit model so that it would be easy to dissassemble if necessary.It only took a few minutes of hammering to combine the pieces.



The back wheels were also cut using the wood.We had rubber sheets available at the lab. We used this to create a traction surface for the wheels.Two layers of rubber were used for each sheet.



The front wheel couldnt be made using wood, since it needed to be ball wheel.we could have 3d printed the wheel, but due to inadequate time, we bought 2 wheels and used them instead.





Setback & Improvistaion-

Halfway through the project, we encountered our first first setback. we couldnt get access to the required motor. The motor we had in mind was the kind that was used in electric wheelchairs. It was too costly for us and we couldn acquire second hand one.So we obtained a pair of wiper motors used in cras. Later we realized that it didnt have enough power to move a person.We had only 2 days left before the presentation, so we decided to change the project. Since we didnt have time to design & build a new topic, we decided to convert already inprogress project to Automatic cleaning machine. the machine would utilise the body we had already constructed along with the motor we had at hand.

The platform intended as the seat of the person will be used to hold the vaccuming mechanism.The projetion of this platform in the back would be used to hold the motors, battery and electronic components.

The next step was making the shaft for the motor and the wheel. The motors shaft length was not the required length. First the required length of shaft was cut using the scroll saw. The shaft was then welded to the gear of the motor .



The next step was to make a simple dust collecting apparatus.

Athif had an idea for this. We Utilised empty plastic bottles and a DC motor for this.The design was very simple.The motor was placed in the bottom of bottle and a fan made of thin slices of plastic was connected to it. There are tiny in the bottom so that when the motor rotates in counter-clockwise direction, the air would be sucked through the mouth of the bottle and dispensed through the holes in the bottle.a net placed b/w the mouth and fan would collect the dust.



Here's a working video of the dust collecotr:



Electronics & Programming

The next step was the electronics assembly. This was the only part of the project where we had to spend money. For the machine, we used an HC-SR04 ultrasonic sensor, 2 IR obstacle sensors,l298 motor driver and an arduino UNO.
Arduino board was used because arsheena's effort to make a fabdruino failed and we didnt a main controll board and time was running out.This problem is explained in detail in arsheena's page.
Arsheen created the required electronics connections using arduino as the main board.



The IR sesnors was mounted left and right side of the body and the ultrasonic sensor was mounted on the front. This was to measure the distance between any potential obstacles and the machine. The program was written and uploaded by Nizam. The program part in detail can be found in nizam's page. After the program was tested and uploaded to the board, we then mounted the entire electronics assembly on the machine and connected them to the motor and sensors. The whole components cost less than 20$. We tried to mill an fabdruino but the traces were too thin and kept being damaged.The ultrasonic sensor was used to detect the obstacles infront and the distance b/w the machine and the obstacle. IR sensors were used to detect obstacles on both left and right.After assembly, The machine looked like this:



We tested the working of the machine. We used a motorcycle battey to power the machine. During the first try, the machine worked fine, but we felt that the battery didnt provide enough power so we used one more battery connected in parellel to the 1st battery. When we tried again, the motor driver shorted out!!! Too much power...

We were able to obtain a working video-





The Download files and detailed documnetation can be found on our respective pages.