Wednesday, December 16, 2009
Monday, December 14, 2009
We finally have our (almost) finished Throwing Machine! We used our original catapult concept using PVC pipes, but we changed our release mechanism. Our current release mechanism is using 2 eyehole screws screwed into each side of the machine- two on the swiveling part and two on the stable piece which does not move. We have a rod that goes through all four loops and therefore holds together the two pieces. When the rod is pulled out, the swiveling piece of the machine is released, and it then throws the ball. We have estimated that the ball can be thrown up to approx. 25 ft., since we have so much potential energy stored from the bungee cords that are stretched very tightly. The mechanical part of the project is the wireless power drill that when powered on, pulls a string that is attached to the rod, which then pulls the rod out after the string is spun around the drillbit. We are still working on improving this method of release in order to pull the rod out easier and make it more compact. We might get a mini hand drill so we don't have to use a bulky power drill, and we can attach it to the side of our project. The only thing we have left to do is find a way to make it wireless, or have something that can press the drill button without the user being so close to the machine. We will have another update in a few days, along with pictures and a Youtube video that we will upload.
Thursday, November 5, 2009
Our group went to the last Saturday Sidekicks meeting on 10/31/09. Brooke presented our first prototype to the group and demonstrated how it works. Our prototype is made with PVC pipes, bungee cords, and part of a "doggie tennis ball thrower". We are going to work on improving the design of our project and cleaning it up. We plan to attach a motor to our release mechanism, which is eyehole screws into both pipes that come together (held together with a rod going through all of the eyeholes). The motor is going to pull the rod from the screws, releasing the moving pipe piece that has the tennis ball on it, creating a catapult-like mechanism. We will have our second prototype done in two weeks, and will have another update on our blog.
Wednesday, October 21, 2009
Today, we finalized our design and decided to change it slightly. We bought PVC pipes, elbows, and Tee pieces to construct our device, which functions like a catapult (tension from Bungee cords). We have the contraption built and put together, we just need a few finishing touches before we finish our first prototype. We need to figure out what we are going to be using for our release mechanism to let go of the pieces in motion (attached to Bungees). We might use a motor with a button connected, or a non-mechanical device that we have not decided on yet. We also need to find a way to attach the tennis ball to the pipe that will be launching it (tba). We will scan a sketch of the device ASAP, and will have another update next week, hopefully with our prototype finished.
Wednesday, October 7, 2009
The beginning of our building process got delayed this week when one of the things we were bidding on E-bay sold before we were able to bid again, and it got too expensive for our liking. We are now going to build our throwing machine almost all by raw materials, most of which we need to go and buy. During the next week, we plan to buy the materials listed below, create the basic structure of our device, and formulate more ideas for the details of our plans. For now, we plan to use wood and PVC pipes for the structure, two small motors to power the "height changer" to control how many balls are being thrown and the other to power the switches used for the buttons. We also plan to use a large, curved PVC pipe (if we can find one) as a chute for tennis ball. If not, we will create a ramp that can be under the spinning wheel that will launch the ball. If possible, we want to have the device planted on a rotating platform, so it can be easily aimed. For the three buttons that will be attached with wires to the platform, we intend to have one button for the actual on/off powering of the machine, one to spin the wheel that will launch the ball clockwise, and the other button to spin the wheel counterclockwise. When the wheel is turning towards the tennis balls, they will be prevented from being launched. We plan to get all of our supplies from Home Depot/Lowe's, Radio Shack, and possibly from a source on the web. Another update will be posted next week.
Items that we need:
Items that we need:
- electrical wires
- basket to hold balls
- 2 small motors
- battery packs
- PVC pipes for structure and large pipe for ball transfer
- 3 switches/buttons
- wood (for structure and support)
- basket/holding device for the balls waiting to be launched