Fabsosh’s Blog

MOBILE FABLAB UNVEILING AND LAUNCH BY THE MINISTER OF SCIENCE AND TECHNOLOGY,

Which was held at the University of Fort Hare, the FabSosh team mentioned that the visit was an eye opener and I must congratulate them on an exceptional display of highly intellectual interactions with school children  as well as adults who visit the Mobile, Fab Sosh Images

DC/AC inverter

The basics for a DC to AC power inverter consists of an Oscillator generating the required frequency i.e. 50/60Hz , a power amplifier using power BJT’s or Power Mosfet for driving the step up transformer.  A 550VA step-up thyroid transformer transforms the pulsating DC from the power amplifier to 220Vac.

This inverter takes in a 12Vdc and convert it to a 220Vac a modified sine kind of output is achieved which is later filtered to achieve a sine waveform.

How does this inverter works:

A battery charger has been incorporated into the design so that it charges the battery when the mains AC power is available and the inverter part is OFF during this time and the AC main voltage is made available on the output. An automatic switch over circuit is responsible for that. When there is power failure or AC mains outage the inverter switches ON, converting the battery voltage to AC.

The casing was designed with Open office Draw and laser cut on the Epilog, circuit boards were milled on the Modela.

See pictures below

Till next time

enjoy

S.Ndlovu

Soshanguve, South Africa

SLA battery cherger

the oscillator

step-up drivers

step-up transformer

the inverter(dc to ac mode)

The circuit board on the left shows the original hello.echo.44 board and the other two are the modified hello.echo.44 boards. The top right was modified by Conty and the bottom right by Tshepiso. all the modifications were done on cad.py. Tshepiso has even replaced the hello text with her initials(TM).

Till next time

Enjoy

S’khumbuzo Ndlovu

Downtown Soshanguve , South Africa

Shapes were created using the Roland 3D design, machined using the Roland modela player together with the Roland Virtual modela for preview, its easy using the Roland modela software i.e Dr.Picza( for scanning),3d engrave ( 3d machining from scanned data), 3D Design ( 3d Modeling), etc. Hope the pictures will explain it all.

till next time!!!

Enjoy!

S.Ndlovu

Soshanguve ,South Africa

3D text design with Roland 3D text by Tshepiso

Tshepiso showing her workpiece

we used an old keyboard button/key as our 3D object to be sacanned.The button/key was scanned using modela software Dr.picza and 3D engrave for machining. its was an interesting experience. I hope the pictures will explain it all. We were experimenting with the modela, so Tshepiso promise to scan more interesting objects( more 3D scanning and printing),..yeah…

scanned button/key on Dr.Picza

scaled-up button/key machined on the modela

tool path rendering on Roland 3D engrave. Ready to sent to the machine

Here is a document I’ve put together back then when I was teaching myself the AVR microcontrollers. So I thought it might be useful. AVR micros are very nice microcontrollers, they are very powerful compared to their competitors the Pic-micros and 8051 variants.

AVR MICROCONTROLLER ISP PROGRAMMING

Men at work building what would eventually become FabLab’s new home. It’s quite an exciting experience.  Moving from an old place to a new place is a bit of a challenge and an exciting experience. We packed materials, removed and rolled cables, components into boxes, moved tables chairs cabinets out, machines one by one they all went out, suddenly the room we used to call it the FabLab was empty and there were no signs that it ever was a our beloved FabLab.

Our Lab in boxes ready to move into a new place courtesy of Rodney and Conty, they really made sure that everything is packed nicely into the card boxes.

Our new FabLab

a tall giant beautiful bird paid us a visit today. tried capturing the best picture I could with my S600 sumsung camera since birds of this size does not always come.

A switch mode computer power supply was used as the basic building block. The power supply has two functions i.e. 1.2V – 17V variable power supply and a lead acid charger. A function selector switch has been provided for choosing the mode of operation.

S.Ndlovu 2009

S.ndlovu

2009