Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: rabadswompe on June 07, 2010, 01:08:19 PM

Title: 50$ robot questions regarding part selection
Post by: rabadswompe on June 07, 2010, 01:08:19 PM
Hello!
I intend to buid the 50$ robot and then upgrade it to the IR rangefinder mod to make it "sumo".

I tried to source out my materials list at the local electronics store... some parts were really easy, others came back with questions...so here they are :

#1- What is the exact Sharp IR rangefinder's model number AND range ?

#2-is the 5v linear regularor positive OR negative ?

#3- Is the 220uF - 16V capacitor ok? (parts list doesn't mention V value)

#4- 340 ohm and 1,62 ohm resistor ok at 1/4V ?

#5- What LED to select (3mm or 5mm )?

#6- What is a good resitance value for the photoresistors ?


Thanks for your help

Yann
Title: Re: 50$ robot questions regarding part selection
Post by: amando96 on June 07, 2010, 02:22:10 PM
#1- What is the exact Sharp IR rangefinder's model number AND range ?

It usually depends on What you want, but lets wait for someone with 50$ robot knowledge to answer :)

#2-is the 5v linear regularor positive OR negative ?

7805, 78 means positive.

#4- 340 ohm and 1,62 ohm resistor ok at 1/4V ?

if you mean 1/4 WATT, yes

#5- What LED to select (3mm or 5mm )?

up to you, i like 3mm, you might like 5mm, the mm is only talking about the diameter of the led casing.
Title: Re: 50$ robot questions regarding part selection
Post by: Choco_liger on June 07, 2010, 05:36:25 PM
1#
Well I got a 4cm to 30cm range. I haven't quite tested it yet but as long as you have an appropriate range. Like, don't get something 80cm - 100cm for example (assuming they exist).

3#
Yeah that should be fine. I think the only thing that matters is the amount of micro farads anyway unless it's really low.

6#
Well 20k for the photo resistors. I think that was the one for mine. Unless your meaning the value of the resistor attached to them. In that case about 1.62K.
Title: Re: 50$ robot questions regarding part selection
Post by: Alfa_Zulu on June 08, 2010, 11:17:14 AM
hey

#1- What is the exact Sharp IR rangefinder's model number AND range ?

    As far as im aware it doesn't matter, just choose a range that suits you, around 10cm-50cm

#2-is the 5v linear regularor positive OR negative ?

    Positive voltage

#3- Is the 220uF - 16V capacitor ok? (parts list doesn't mention V value)

    The voltage doesn't matter, normal rule of thumb is higher rated voltage the better (but keep it realistic for you project)
    like don't use a 450V cap in a 5V circuit like me lol (that's all they had left in stock).

#4- 340 ohm and 1,62 ohm resistor ok at 1/4V ?

    I think you mean 1/4watt which should be completely fine

#5- What LED to select (3mm or 5mm )?

    as already said this is just the casing diameter, only worry about it if your fitting it into a housing.


I know most of these were already answered but I'm just offering my opinion  ;)

    Alfa.