Spider Robot Platform

[airman00]

OK this is a two part question

First Part: What are the differences between quadrapod robots and hexapod robot ?  Besides Hexapod having better stability.

VS.


Second Part: 
Do you think it is possible / worth it   to make a hexapod or quadrapod from scratch or to just buy one ready made?

[cooldog]

depending on the price i would say buy them

the cost of the servos and costom parts will kill u

[Fredrik Andersson]

Oh yes, it's very possible. In fact, I and a team on school is working on a hexapod robot.

We bought the cheap GWS S03T servos, which, though they are pretty oversized (they wont fit SES brackets, the ones Lynxmotion uses) is still performing really well. My own experience of them is that they have very high quality, no twitching, varying strength and speed on every unit of them. Google for them, they are only $10 a unit.

The difference between a quadropod and a hexapod (besides the number of legs) is that you can only receive good and easy results moving one leg at the time with a quadropod. I guess you could program a gait that makes it move two of the legs at one time but that would be pretty hard to get good working. The hexapod however is able to lift three of the legs while still standing stable. I would definitely go for a hexapod (and well, thats what i did) because of the much more possibilities it gives you. The extra possibilities is worth more than the cost of the extra servos and such.

Check out my thread about our project: http://www.societyofrobots.com/robotforum/index.php?topic=2777.0

[airman00]

thanks


will you be making a tutorial?

[Fredrik Andersson]

Yes

[Ro-Bot-X]

What I really like about hexapods is the possibility of using the front 2 legs (while standing or moving on the other 4 legs) to manipulate small objects. I would also add another degree of freedom to them to allow the tibia to rotate to be parallel with the ground. The robot would be able to pick up objects and store them on it's back in a special basket. Also, the tip of the tibia would be fitted with some sort of hooks to better grab the objects.

[Admin]

What are the differences between quadrapod robots and hexapod robot ?  Besides Hexapod having better stability.

Well, since quads have fewer legs and fewer servos, they are much cheaper and require less battery power.

Hexapods can lift more weight, since it has more legs.

You don't want a wide stance with a quad (unlike your pic). Watch how a dog or horse walks/runs, and you will see that the legs are really close to each other - this greatly improves stability.

Do you think it is possible / worth it   to make a hexapod or quadrapod from scratch or to just buy one ready made?

The build or buy argument. The more you do custom, the more you learn and the more 'I did it myself' pride you can claim. But buying it will save you time and it will probably work better too. Cost will probably be about the same. Ask yourself what your goal of building that robot is, and the answer will come

[airman00]

Cost will probably be about the same.

thanks, that was what I was most interested in

[paulstreats]

Also a robot that you build yourself can appear in a portfolio/resume for future employers, unlike a kit that you buy a build from instructions

[airman00]

Also a robot that you build yourself can appear in a portfolio/resume for future employers, unlike a kit that you buy a build from instructions

true,


i was most worried about the cost for the hexapod


b/c if I would spend considerably more on a homemade version then a bought version , i would go with the bought version

[Fredrik Andersson]

We get off much cheaper with building our hexapod ourselves. Although the metal plates we used was donated to us by a local roof plating company. Guess you could find some place to get that as well. The plates we got was just spare sheets for them, even though it was enough for the whole project, so it was no big deal for them to give it.

[SmAsH]

ive made one before but i only programed it to move in four directions (via remote control keypad) i want to try and make it atonimous.... gonna be really hard tho oh well im always up for a challenge.

[Fredrik Andersson]

ive made one before but i only programed it to move in four directions (via remote control keypad) i want to try and make it atonimous.... gonna be really hard tho oh well im always up for a challenge.

Hey, could you explain more about that one? Did you build it completely from scratch or used a kit? I would be really interested to know more about this if you made it from scratch.

[SmAsH]

4 close friends and i made it from scratch use help from school (teachers let us use special programes and utencils)
took us like 3 terms tho i can talk to you about it if u want...do you have msn?

[paulstreats]

Maybe you should put it on your website......

It is a much more accomplished task to build a quadruped or hexapod....

What controller did you use to move the servo's?

[airman00]

ive made one before but i only programed it to move in four directions (via remote control keypad) i want to try and make it atonimous.... gonna be really hard tho oh well im always up for a challenge.

I want to see pictures man!

[SmAsH]

ya ya ya....i dont have any pics or specs. theyre all on the team laptop which is locked in the school....so. ya

[airman00]

well email it to me when you are in school