Finally a quadruped project of my own. 8) Some brief information of my robot and my short and long term plan.
[size=100]ROBOT PROFILE[/size] Name: Sleek Robot type: Quadruped Leg design: 3-DOF (phoenix leg) Controller: Microchip microcontroller (Currently experimenting on PIC16 and PIC18)
[size=100]Project Features[/size] 1. A walking quadruped (omnidirection, straight line) 2. A walking quadruped with inplace rotation, curvature gait. (True omnidirection) 3. RC Remote controller incorporated
[size=100]Nice-to-Have Features[/size] 1. Dynamic gait. Something every quadruped builder dream off
Sleek design is actually a direct scaling of Phoenix, from 6 legs to 4 legs. I am using Phoenix sexy legs, while rebuild the chassis. The chassis will also incorporate Phoenix signature curve, and a matching center cut-out.
Quadruped walking gait will be largely based on Oricom literature.
This is my first draft (paper cutout ) of the chassis, side by side with Phoenix chassis. It’s very compact, and could hardly fit the 5 cells rechargeable battery. Maybe I’ll stretch the model just a bit. img218.imageshack.us/img218/4586/p1020125.jpg
So I increase the size (length and width) by about 10%. I use acrylic for the body, 3mm for top piece and 4mm for bottom piece. I wish I have aluminum, or polycarbonate, but they are just hard to come by here, especially in small quantity (with reasonable price ). (I have some 5mm polycarbonate though, but that is just too thick ) I still prefer acrylic, they are easy to work with.
It’s surprisingly stiffer than my expectation. It is also slightly lighter than phoenix aluminum body. Here’s some update.
Unfortunately, acrylic. Aluminum are hard to come by, and also difficult to work with. Prototyping is expensive in my country, especially that require specific machining. Not to mention it is almost impossible and time-consuming if I were to make it out of hand tool Acrylic is the next best thing.
I reserved those for future and important updates, so that any guests who visit this thread can get an overall picture and information of the robot by reading the first page! 8)
As for now, since I just started, I’ll post even the smallest detail up there. I’ll remove some of the content and tidy things up once it get too congested
Great work. Smart to use the standard phoenix legs on your design. They really match the shape of the body. What batteries are you planning on to use. It looks like it’s going to be a tight fit.
The pictures are showing different kinds of servos. What type are you planning to use?
How are you gonna control the quad?
About the updates, personally I think it’s better to place updates in a new post at the end of the topic. People who are following your project will be noticed when there is a new post and only check the end of the topic. I never start reading from the beginning of a existing topic and read everything over again.
Thanks Xan. Point taken, I’ll update as new post then, the first page will be use for summary, pictures and videos. (Since I can’t delete it )
I bought the 2800mAh NiMH from Lynxmotion. I just did a trial fit, it’s too tight! The aluminum connector is pressing on the battery, kind of worry me there.
I’ve survey some local RC store for Lipo cells, planning to get one of those 7.2V 4000mAh, after I figure out how to regulate the voltage
I have the phoenix kit, servos, except the electronics (SSC-32 and atom pro). I have made allocation for the SSC-32, (hence the center cutoff of top piece which is identical to phoenix), maybe in the far future.
Meantime, I plan to develop my own PWM generator, and a separate controller for IK and third controller for gait generation.
I had the same thing about the battery being a tight fit. I’m using this voltage regulator in combination with a Lipo. It’s pretty small and works perfect!
I’m into light metal, I like the way 6061=T6 aluminum machines. Makes for a very strong chassis.
What center-to-center distances do you have for your servo horn mounts? I think mine are 5" x 7". I noticed that your mounts are on a square. Makes for a very tight body! I’d put in one or two 1/4" holes for some switches. Maybe you have already.
Let me know if I can help in any way. We have similar projects!
Yeah, I’m up to 15 drawings for just two bodies built so far. I see you make up trial parts out of paper as well. I call them “puppets”; “paper dolls” just didn’t sound right.
Your layout IS small! I trust you checked out the swing of the Phoenix legs? I’m using smaller legs.
A new circuit board too! That can really be a chore. I’ve been able to mill a few of mine (isolation). The latest is for a Micromouse.
Where did you find the aluminum spacers (connectors)? The 1.875" length doesn’t seem to be standard. And I don’t see them listed on the LM website (hint). Or maybe I missed them!
I should probably investigate the LiPo batteries as well. Oh well!
I have a hexapod chassis made of 1/4" Polycarb. Nice stuff! I found a cracked floor pad used under desks, that provided me a lot of free material. I haven’t gotten around to making an aluminum chassis (body) for it. Acrylic looks nice; but as you’ve observed, it cracks!
Here’s some update. The SES is now properly mounted on the chassis. I did a dimensional check, the errors are around +/- 0.3mm, which is pretty good. Here is the picture of SES secured on the chassis. Hope this answer your question Alan.
While waiting for hobbycity to restock, I ask around another forum, of suitable voltage regulator method. I was thinking of switching regulator, then one of the forumer suggest using diode to kill the voltage. Any comment?
I’m using scroll saw to cut the body, then did some filing to get the desire shape. Guess I’ll be waiting for the regulator then. It’s going to take some time! Meantime I’ll be working on the code, the PWM and IK first!
) of the chassis, side by side with Phoenix chassis. It’s very compact, and could hardly fit the 5 cells rechargeable battery. Maybe I’ll stretch the model just a bit.
Acrylic is the next best thing.
! Thats the right word… 
