Tuesday, March 17, 2009
Friday, March 13, 2009
This is the Final CAD lay out of our Robot for the 2009 Robogames Competition. I decided to go with the Double Knee configuration , for the proposed running attribute. The Chassis Specification are 1.7 lbs machined parts, 51cm tall, 24 DOF. Incorporated in the feet are also custom XYZ Force Torque sensor for foot landing data collection. The colors are the proposed Anodizing scheme, but that will come later. I know what you want to see the real thing right? Wait for the next post...the Manufacturing!
Thursday, March 12, 2009
This is the "Bent Knee" approach I prototyped. Notice the distinct feature of the the knee motor is set a 45 degree angle normal to the ground. This I believed allows the robot to lift its leg to take a step with out it needing to swing the lower half of the knee out as far in order to progress forward. Also the ankle pitch does not need to rotate to maintain keeping the foot parallel to the ground. The design uses what I defined as stacked axes , which is the pitch and roll are offset from each other in height. Thou being a clever set up of the motors, that was the down fall why we did not go with this design. As a team we decided we wanted all pitch and roll to be fall on the same plane for the hip and ankle motor orientations. Below is closer look into what I described as the Gate motion of this prototype. I guess it is shelved for now but I may want to revamp it for a future candidate.
Saturday, February 28, 2009
To build a mini robot you need to have small motors to drive the articulation of each joint. In Hubo's case It uses a complex set of multiple motors and drive belts in combination with Harmonic Drive systems to produce movements and have holding torque to stand and move. This method work wonders for Hubo but is not a good system for a small system for reasons that it is bulky and very expensive. On top of the mechanical complexity it needs to have custom motor controllers to drive the motor train as well. Small Humanoids can use a off the self package that includes a motor, gear set, encoder, and controller. These servos are far more cost effective, light weight, and have far less overhead to program the included controller. The servo package we chose for this project is the Robotis Dynamixel. Robotis is actually a Korean based Company that sells robot kits such as the Bioliod Humanoid. They sell many other accessories and servos for people interested in building custom Humanoids like ourselves. We deiced to go with the RX-28 that supplies 28N.m of torque for leg servos and RX-10 (10N.m) for the upper body.
I liked the legs where the knee joint is set on an angle to the perpendicular part of lower leg and foot. This allowed the robot to have a very fluid motion during walking. I also felt it did not have to Throw its leading and trailing leg as far to achieve locomotion.
The second design that also took my interest was a small robot also from ROBO - ONE. This robot is called OmniZero.
The video shows the unique construction of the robot, notice that this robot has two motors at the knee joint. The double knee is much different than most Humanoid robots competing. Most robot have a single motor actuating at the knee, but in using two motors in the knee allows each motor to rotate half the distance. This allows of for faster actuation at the knee and I believe that this is a potential design for a more capable running robot.
Feb. 9th - 11th Finalize Robogames CAD of Legs/ Feet
Feb. 12th - 14th Produce CAM with MasterCam of the Legs/Feet
Feb. 16th - 17th CNC parts at Hubo lab
Feb. 17th - 21st Torso/ Arms Finalize CAD
Feb. 21st - 28th Produce CAM for Torso/ Arms
Mar. 1st - 7th (Overflow) CNC of Torso/Arms
Mar. 1st - 7th Start MasterCam Documentation for tutorials completion April 1st.
Mar. 7th - 13th Rap up loose ends with Hubo 2 CAD and Documentation
Friday, February 13, 2009
Wednesday, January 14, 2009
Bryan and I watched our first Eagles Football game in Santa Claus Bar on Monday after work. We knew the final score...but we still had allot of fun!
Sorry for the quality of the picture but here is the proof that we watched the Eagles beat New York Giants!!! WOOOOOO Next Game here we come!!!
On Monday the 12th Jeong Hoon Kim, famous Pop Singer visited the Hubo lab for a photo shoot with the stylish Hubo. Dr. Jun Oh built the singer a 7 degrees of freedom motion platform stage that was used in his concert performances. I had the the opportunity to be the Stutman/Testing personnel when Mr. Kim was producing his Choreography at KAIST with this platform featured below. In my good spirit I dressed up in full body pads and gave the group some smiles and laughs for the late evening/morning. Mr. Kim invited us to his concert but we could not make it! But he did recognize me and made an effort to come over and talk with me! Such a nice Guy!!
Friday, January 9, 2009
Thursday, January 8, 2009
It is a true achievement to show chase my skills permanently even after I leave and it truly shows that my CAD is accurate for all the pieces did fit together seamlessly. I also learned many valuable skills with working with secondary companies that I did not expect to learn from my PIRE experience.