COTS Parts made just for FIRST Robots

[Robomaniac928]

i would definatlybe interested in a FIRST shop i think i whould carry gearboxes shafts wheels sprockets chains and and any other part that would be nessasary to build a good drive train and i twould be great if they cariied omni wheels because i dont know about anyone else but i have been searching for a while but i cant find any that are what i need. it would have to be reasonably priced with a quick ship time as well

[Paul H]

Robomaniac928, have you looked at AndyMark?

[John Gutmann]

Originally Posted by cdr1122334455

An adaptor for that you could use a servo to switch the AndyMark tranny instead of the Pneumatic shift. Also a servo shifter for the Dewalt Transmission too. I'd price them about $30-$45 range depending on the price of the design and the servo.

my team used a servo for shifting of the dewalt transmission, we found out how in one of the white papers

[Gdeaver]

I'd like to see a add on optical encoder module for the KOP transmission. All that would be needed would be a gear meshed to the output gear with a 1/4" shaft. There are optical quadrature encoders that can be had for less than 1/2 the cost of the Grayhills. A code wheel with a dual photo interrupter module could be done for even less. Add a coprosessor to handle the counting. Make it programmable so that it could be set to pull a pin low after so many counts. Also the current count and calculated velocity could be sent out to the TTL serial port either by query or every so many ms. Add some interface code in the default code and there would be no reason for any team to sit and do nothing for autonomous next year.

[mechanicalbrain]

The one thng i have trouble getting (at least the right type) that a number of teams do is tread. It would also be nice to see specialty materials like square carbon fiber rods. it costs just over $120 to make a 20 ft length with i believe 1" per side. Actualy its not hard to do and if you contact me ill list some suppliers and tell you everything you need to know to make some. Im not telling Why i know how to though!

[Matt Leese]

Originally Posted by sparksandtabs

my team used a servo for shifting of the dewalt transmission, we found out how in one of the white papers

What you didn't really add was that it never worked particularly well. The servo barely had enough power to shift the transmission and sometimes it would get stuck out of gear. If it were done again, it would require two servos shifting each DeWalt (at least).

Matt

[Sparks333]

Originally Posted by Matt Leese

What you didn't really add was that it never worked particularly well. The servo barely had enough power to shift the transmission and sometimes it would get stuck out of gear. If it were done again, it would require two servos shifting each DeWalt (at least).

Matt

You want to be careful with that. It's popular method with RC model airplanes (the really big ones, like 33% Extra 300's) to gang two or more servos to make a really big control surface move (I have most often seen this in the rudder, though there are often more than one servos driving each aileron) and I have seen some articles about how they can fight each other if not calibrated correctly, reducing battery and servo life. There are COTS parts that keep them from doing this, but I don't know how they work.
Just something to look into.

Sparks