156B Week 6
Overview of Status of Analysis, Design, Fabrication, Tests, etc.
We are now beginning to come up with design soltions for the breakaway and flexible link.
We are also coming up with design solutions for increasing the natural frequency of the arm with hardware upgrades.
We are continuing development of the control interface.
Specifically, how to define our own motion profile and obtaining the time history of the joint angles to be sent to the motors.
Accomplishments from Previous Week
Finished dynamic model (testing and verification)
Learned how to obtain real-time data from the motors.
We figured out how to input time history of joint angles.
We just needed to change the baudrate of the micro-controller. the baudrate between MATLAB and microcontroller matched and was able to communicate properly. However, the baudrate between microcontroller and motors didn't match which caused communication errors.
We figured out the motor's velocity profile is trapezoidal.
See vel.jpg below.
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Try to figure out if Solidworks torques and empirical torques are related by a constant.
Try to find a more accurate method of obtaining empirical torques.
Start looking into ways to improve shoulder assembly. (Beef up shoulder and torso bearing)
Input MATLAB motion profile into the robot motors after filtering.
Determine how to define our own motion profiles.
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Instructor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Point of designing a flexible link: to decrease natural frequency of the arm and bring it close to the control frequency.
Point of designing a fuse link: to have the robot arm break at a certain torque during the motion profile.
Two specializes joints are still high priority.
Comments from Other Students in the Class (indicate date of comments and if via email or in person)
Risks and Areas of Concern
We can't access the motor terminals, and therefore, we cannot obtain analog signals of the voltage and current.
Serial communication and data transfers are still a little confusing conceptually. I can play around with the controls to try to figure out, but I do get worried I might break something.
Resources or Information Required but not Available
Schedule
Be able to define motion profiles to be sent to the motors. Simulate the kinematics of any motion profile.
Budget (list amount spent and amount remaining)
Progress on Report and Webpage