“Basic” chassis

[TYKE]

Hi
I am going to build my first robot mainly for fun but also to to try out my programming skill and to use as a test bed so I am looking for advice on building a “basic” chassis that will run on carpet. For a start I have been looking at the dual motor/gear boxes available can anyone give me any pros & cons for these units

 

[hippy]

[ Moved to Active Forum ]

 

[slurp]

Do you mean the Tamiya motor/gear boxes?

I've got one in a mini-sumo, they're not bad but you'll have to be careful with motor driver / picaxe power supplies to avoid noise and drop-out issues.

With the Tamiya boxes can be easibly attached to a plate acting as a chassis, the example linked above is aimed a smooth painted surfaces - hence two weeks and a skid!

I've not had any problems driving with an L293 (not the D varation) but I've not been stalling and pulling the higher currents outside of start-up.

Best regards,
Colin

 

[westaust55]

And if your motors are higher current rating or might get into a stall situation where the L293D current rating is exceeded, then consider the SN754410 which can drive 4.5V up to 36V at 1A continuous output current. This is a pin to pin compatible alternative for the L293D.

 

[slurp]

And if your motors are higher current rating or might get into a stall situation where the L293D current rating is exceeded, then consider the SN754410 which can drive 4.5V up to 36V at 1A continuous output current. This is a pin to pin compatible alternative for the L293D.

That matches my expectations of L293 vs L293D

http://focus.ti.com/lit/ds/symlink/l293.pdf

best regards,
colin

 

[Rickharris]

Hi
I am going to build my first robot mainly for fun but also to to try out my programming skill and to use as a test bed so I am looking for advice on building a “basic” chassis that will run on carpet. For a start I have been looking at the dual motor/gear boxes available can anyone give me any pros & cons for these units

These geared motors are good for first robots - they result in a fairly slow robot unless you use big wheels - CDs turn out fairly good.

Rapidonline have a reasonable selection of bits and useful stuff because they deal with the educational world. Although other places can be cheaper Rapid are fast and hold big stocks.

At school we glue gunned these motors to a CD with a 3 AA battery box under the CD to keep the centre of Gravity low - and drove them with a 08M and L239 no problems - Simple touch sensors from micro switches for bump and go. Even some line followers were made using Rev eds line detector module.

For us a complete robot came out at around £7

 

[TYKE]

Thanks everyone for the replies it has given me a lot to think about.