Applications and Implications
What will it do?
-My Project will be able to project ping pong balls at various speed and spin rates. By speed, I mean the m/s. By spin, I mean rps as well as the axis on which the ball will be rotating (degrees). I’ll get these numbers in and the wheels should be able to turn accordingly. The ball should be able to to move from a speed of 0 m/s to 10 m/s.
-Needs to be able to be mounted on something for a solid position
-Needs to connect to the ball feeder and the pan/tilt head
Who's done what beforehand?
-123D Catch Example
-Robo Pong 2050
-Gears
-Homemade Table Tennis Robot
What materials and components will be required?
-I will be using acrylic for the structure surrounding the wheels.
-I will also use bolts in order to secure the motor to the acrylic.
-I will be using two hextronic DT700 brushless motors
-Speed controllers, and a servo board.
-Servo motor
-I will also use 3D printed material for the wheels.
Where will they come from?
-Everything except for the brushless and servo motors will come from our fab lab inventory.
-The Brushless and servo motors will be ordered online from www.hobbyking.com.
How much will it cost?
-Brushless motors (2): $9.81 + tax, each.
-Servo motor (1): $4.59
What parts and systems will be made?
-The structure to hold the wheels and motors in place needs to be assembled.
-The wheels need to be 3D printed.
-A control board: Speed Controllers, Servo controller, Network interface
-A structure that can rotate along 180 degrees
What processes will be used?
-A networking process needs to be used in order to connect the speed controllers and servo to the rest of the table tennis machine so that the motors can read inputs of different speed and spin rates and produce output accordingly.
-Control each motor
-Rotation of axis
-The board would have three connectors for each motor and a three pin connector. Power supply connector, and network interface connector.
-3D printing – wheels
-Laser cutting – acrylic
-Output devices – motors/servo
-Input Devices - measuring the speed/rotation of the ball
-Network and interface – connect the incoming information across nodes
-CAD 2D and 3D design – designing the hold structure and press-fits
-Embedding programming – control board
-Application and Interface programming – testing data input/output
What tasks need to be completed?
-3D design a wheel with multiple material characteristics
-3D print the wheel
-Assemble holding structure for the wheels/motor
-Assemble Speed Controllers
-Program speed controllers
-Program Servo Board
-Connect board and controllers to a network
-Develop speed/spin calculations from speed/spin to motor rpm and servo pulses
What questions need to be answered?
-How to merge multiple materials on one 3D printing?
-What components and structures are necessary for designing a brushless speed controller?
-What are the dimensions of the adjacent projects that my project needs to connect to?
-What are the speed and spin rates to be calculated and inserted into the code?
-How do we keep the holding structure from moving when the ball moves through the wheels?
-How to rotate the structure 180 degrees?
-Is high speed photography the best way to determine if the ball is actually traveling at the desired speed/spin/rotational rates?
What is the schedule?
-Friday, 5/10/13:Full test structure assembled with test wheels
-Tuesday, 5/14/13: Actual structure assembled with actual 3D wheel printed
-Friday: 5/17/13: Servo board and test speed controllers programmed
-Tuesday: 5/21/13: New speed controllers actually programmed
-Friday: 5/24/13: Everything connected via network and tested
-Tuesday: 5/28/13: Problems from previous test troubleshooted and final product shown.
How will it be evaluated?
-Does the structure stand alone and is it strong enough to hold all of the necessary components?
-Is it actually projecting that ball out at the desired spin/speed/axis rates?
-How often does it project the balls?
-How fast can it change spin/speed/axis?
-Consistency?