First, I must say that this project has been more of an experiment since I have choosed to try some cheaper servos. Of course you almost always get what you pay for. The servos I’m using does not have the same quality and precision like you get from Hitec or Futaba. But they are strong and have MG geartrain. Here is a picture of my new coxa design: http://i214.photobucket.com/albums/cc6/ZentaOlbaid/OxyopusCoxa.jpg
Having low weight in mind from the beginning of this project has been very important. These servos has a relative low weight (low quality = low weight? ) The low profile servo has a torque of 7,4 kg and the standard sized servo has a torque of 9,7 kg and their weight is 33gr and 48gr. I’ll also use this low profile servo for the tibia part.
The coxa design is very simple, but has very low weight and was quite easy to make.
Wow , this is a great desing! First real octopod I’ve seen for a while, and I see you’re going more the way of small lighweight inexpensive servos for a lighweight rbot more than the traditional beefy body with beefy servos that en up costing you an arm and a leg.
I know I already said it but I love this design! it’s nice and sleak. i have a feeling it’s going to walk pretty fast! i can’t wait to see it walking, t will be almost hypnotizing to see the eight legs advance in perfect coordination!
and, finaly I completely agree with you about panting those thing black, it just dampens the style.
Can you show us you’re drawings of the femure and tibia?
Alan: I choosed not to use ball bearing on the underside of the coxa part. I used ball bearing on my Phoenix. On Oxyopus I have used some custom made brass bearing, you can see them integrated on the picture of the lower bodyplate. I think they will do the job. I’ll mount the SSC32 inside the body this time. And hopefully there is some space for a motherboard too, in the future
Tyberius: Yes, I hope the LiPo’s and the BEC’s will do the job.
Sam: I’m looking forward to see it walk too . I’m not sure about the speed though . But since the total weight of Oxyopus without the battery are almost the same as for Phoenix, it will have a very good weight/power ratio. I think the total weight for Oxyopus will be a little bit over 1,9 kg. Phoenix’s weight is 1,8 kg.
Thanks for the tip. But I’ve already sprayed them black. It seems OK and I have already monted them but I had to be careful not to fasten the srew to hard, some of the paint did (as you mentioned) crack of.
wow! This octopod is wonderfull! I love how thw curve in the femur would give more flexibility and looks really cool with all those curves, looks like a spider-web or like the batshaped weapons of batman…
It adds lots of style! thumbs up
But, what I didn’t exacly get is, you use low profile servos on the tibia because the legs don’t have a lot of space between each other, so you need the smalest servos to get the biggest gait you can get?