Jiaji Li has succeeded in building a prototype Robotic Rowboat. I have used 3D printing technology ever since it was introduced decades ago to build spatial mechanisms and routinely failed, which is why this is a particularly satisfying outcome.
He convinced me to buy an inexpensive 3D printer and said he was sure PLA (poly lactic acid) would provide a strong but light-weight product. So I gave it a chance and find the result to be very nice.
Students at BYU formed a study group advised by Prof. Denise Halverson to explore Kinematic Synthesis. They invited me to join them to discuss Quaterions and how they are used in Kinematics.
I have not talked about this material in some time, so it was interesting pulling together the theory from many past talks, but I soon became afraid that I was assembling a short course, not a lecture. So I took a different approach.
Here is a video of the lecture. The notes that I prepared are posted below.
My Quaternions in Kinematics presentation is posted here.
https://mechanicaldesign101.com/wp-content/uploads/2023/10/BYU-Zoom-Lecture.jpg6911600Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2023-10-18 11:27:502023-10-19 08:57:06Quaternions in Kinematics: BYU Lecture
In this book, we present the detailed design of mechanical walking robots that are driven by a single motor. These walkers rely on specially designed leg mechanisms coordinated by gear trains in order to walk, rather than multiple computer controlled motors per leg. The result is a simplified walking robot that provides a platform for other mechanical and electronic functions.
Two, four and six legged walkers are presented that implement different types of leg mechanisms and power trains. In each case, we provide drawings for a laser cut wood or acrylic chassis, 3D printed parts and a complete parts list. Several of the designs implement an additional motor for steering as well as electronic components and software for speed control.
Our goal is to provide enthusiasts of all backgrounds what they need to build a walking robot at home, to explore new design ideas, and, perhaps, to enjoy the operation of one of these robots as it moves across the ground.
While isolated to slow infections of the Coronavirus, over 60 UCI students learned how to apply the principles of Curvature Theory and Finite-Position Synthesis to the design leg mechanisms for mechanical walkers.
Their first team project was a four-legged walker that used the coupler curve of a four-bar linkage positioned using a skew-pantograph as the foot trajectory. Here are videos that show animations of their walkers
This is the first video:
And this is the second:
The final team project used finite-position synthesis to design function generators to drive the hip and knee joints and guide the foot trajectory. This mechanism is a generalization of the Jansen leg mechanism. Teams of three students designed the leg mechanism, the drive system and assembled them into a six-legged walker. Here are the videos of these walkers.
This is the first video:
And this is the second video:
The variety of these walkers show the versatility of the kinematic synthesis procedures, as well as the creativity of the students. It was a pleasure working with the students on these projects even with the challenges of remote instruction.
https://mechanicaldesign101.com/wp-content/uploads/2020/06/Six-legged-walker-team-12.jpg6741600Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2020-06-15 13:52:472020-06-15 13:55:03The Design of Mechanical Walkers: Spring 2020 Student Projects
Please see our Singular Designs web-site. We look forward to providing our MechGen synthesis software to simplify your linkage design process in SolidWorks. Also see Mechanism Generator.
https://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.png00Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2014-08-04 04:17:402022-07-08 19:56:51Singular Designs is now on-line
UCI’s CNG racecar “Delta” is being readied for competition at the 2012 Energy Invitational. An on-board video of the first run of this race car can be seen at on the web-page: UCI Racecar Engineering.
https://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.png00Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2012-05-10 05:53:082017-01-25 08:09:52UCI’s CNG racecar “Delta” is preparing for EI3
UCI’s race team will field its gasoline powered FSAE vehicle “Epsilon” at the 2012 Energy invitational. This vehicle won 1st place in fuel efficiency at the 2011 FSAE West competition. Some of the team leads who guide UCI’s race car engineering program are show below with Epsilon.
UCI Team leads
https://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.png00Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2012-05-10 05:49:552017-01-25 08:10:50UCI’s FSAE racecar “Epsilon” to compete at EI3
UCI’s electric racecar “Gamma” has an electric motor at each wheel driven by a pack of Lithium-ion batteries. It just completed a test run and is being prepared for the 2012 Energy Invitational at Adams Motorsports Park on May 20th.
https://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.png00Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2012-05-09 20:55:552017-01-25 08:11:53UCI’s Electric racecar to compete at EI3
The Los Alamitos HS race team has been invited to the 2012 Energy Invitational at Adams Motorsports Park based on an excellent performance at the Design Review at the 2012 Youth Expo. They will compete agains race teams from Tustin, Pacifica, Esperanza, Huntington Beach and Foothill High Schools.
https://mechanicaldesign101.com/wp-content/uploads/2012/05/LosAL-Cart-2.jpg675900Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2012-05-09 01:54:482017-01-25 08:51:54Los Alamitos HS race team to join 2012 EI3
The Esperanza HS race team has been invited to the 2012 Energy Invitational based on their performance in the Design Review at the 2012 Youth Expo on April 13 at the OC Fairgrounds. They will join Tustin HS and Pacifica HS at Adams Motorsports Park on May 20th.
Esperanza Vehicle 2
https://mechanicaldesign101.com/wp-content/uploads/2012/05/Esperanza-Vehicle-21.jpg12001600Prof. McCarthyhttps://mechanicaldesign101.com/wp-content/uploads/2016/07/mechanical-design-101LOGOf.pngProf. McCarthy2012-05-08 20:45:462017-01-25 08:47:35Esperanza HS race team preparing for EI3