Shane Tornifoglio Page 1 of 6. Weekly Report 6 2/29/10

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1 Shane Tornifoglio Page 1 of 6 Week 1 Feb 22 nd March 1 st This meeting marks the first meeting in three weeks because of no meeting the week before spring break and then bring break itself. The first week of this three week period I spent a lot of time going through all of the connections and planning the wiring of the entire electrical system, as mentioned in the last meeting I hadn t thought about the connections of each component. To get a better idea of the system I went the Visio image and went through each attachment and component looking for every connection. This helped in identifying the different connection sizes and types necessary. It was at this point I tested the current components available which included the actuators, inverter, console, and Philips LCD DVD player. They all worked according to plan. After going through these testing and planning of the system it was determined that crimping connectors would be my best option. On Digi-key this week I ordered a kit full of crimp connectors and some separate larger connectors for the larger AWG wire. This order was submitted the following Monday. Upon testing the actuators I found an important discovery: the two smaller actuators have limit switches to stop when they are fully extended or not extended at all, however the larger actuator does not have any limit switches build in. This is an issue because if the actuator goes beyond its length allowable length, it spins in place and could potentially unkey itself from the threads. Therefore I have also put a few limit switches on the P.O. This was an unexpected design so after discussing the issue with Drew we have decided that the best way to implement the switches is to integrate them into the I-beam and not the actuator. This causes less wiring and is easier to attach. The limit switch is literally a button that would become depressed, opening the circuit, to prevent current flow to the actuator. This past week I also spent seven hours milling. This was my first time working with the machine shop equipment since August. It took me some time to become reacquainted with the machines. However, the shop techs were very helpful in getting me situated. My primary focus in the shop was milling the swivel base. The swivel base goes at the bottom of the console to allow for the swivel movement. I started with a solid aluminum cylinder measuring four inches in diameter and three inches in height. I milled the cylinder down to its appropriate height of 2.25 inches, a half inch whole through the middle, a 2.5 inch rectangular chunk out of the bottom, and counter bored a.75 inch circle in the top leaving a.25 inch lip. The finished swivel base can be seen below.

2 Shane Tornifoglio Page 2 of 6 Week 2 March 1 st March 8 th This week I continued milling for almost the entire week working on the tilt bracket to fit into the swivel base shown above. This part took 15 hours to mill and was a real pain. The reason for it taking so long was the fast that I had to first use the lathe to take down the diameter half an inch which took around an hour and a half. Another issue with the cylinder base I started with was that the height was too tall and the tech s said there was no way to cut it using a saw safely, so I used the lathe to go from a diameter of four inches down to nothing on for a length of 1.25 inches, this process took about three hours. The next step was to mill down a rectangular chunk three inches deep going at 0.05 inches at a time. Needless to say this took 60 passes and each pass took around five minutes to complete going at such a slow feed rate of 3.0, as recommended by the shop techs. Once the rectangular pocket had been milled down the next step was to drill the hole in the bottom to it can be bolted to the swivel base and the frame so that it could pivot freely 360 o. This hole took maybe fifteen minutes tops. After the hole was completed I needed to mill a radius around the top for the console stand tubing to fit snugly on top. The radius took roughly two hours to complete because of mounting the bracket sideways in the miller was challenging and only one side could be cut at a time. Once the radius was completed the eight holes for pins to be locked into needed to be drilled on each side of the bracket as well as the locking mechanism holes to align with the pivot base. These also could only be done one side at a time and took three hours. When all of these holes

3 Shane Tornifoglio Page 3 of 6 were finished I needed to test the fitting of the bracket in the base, and of course it was too tight. I went back to the lathe and took off another tenth of an inch. The finalized tilt bracket can be seen in the overall picture of the bike in the swivel mount bolted to the frame near the front of the bike. Week 3 March 8 th -15 th (Spring Break) I came back to campus on Wednesday after having my wisdom teeth removed on Monday and all of the Digi-key parts that I had ordered had arrived. I immediately began by building the voltage regulator using the capacitors, resistors, and LM338 regulator. The first problem I noticed right off the bat was in the conversion from Multisim to Ultiboard the LM338 regulator changes packages. I assumed the pin order would remain the same in the transition, however it did not. This took some trial and error with the actual circuit building and testing to figure out. Once I understood the problem I redid the pinning in the Ultiboards for all three regulators. I also spent some time using trial and error referring to the datasheet for the rocker switch to understand which pins were the input and which were the separate outputs with each rocker direction. Once an understanding of the rocker was comprehended I did the same with the relays. I ran into an issue with the relay with an interpretation of the specifications. It listed the activation voltage as 1.2V (min) to 7.8V (max). I took this to mean any voltage in that range will activate the second circuit in the relay. In reality that meant the activation voltage must be greater than 7.8V and once it drops below 1.2V it stops. This was an issue considering the voltage regulator I had planned only went to 5V, which was lower than the needed activation voltage. Once I adjusted the output voltage of a regulator to be 8V, by changing the R2 value in the circuit given in the LM338 datasheet, I tried using the relay again. However for some reason, I still don t know why, the relay causes a voltage drop down to 1.3V when using the circuit, however when using a controlled 8V from the box it works fine. I changed the circuit again giving the output 10.5V and that worked fine with the relay. I documented the new values and made the necessary changes in Ultiboard. I then decided to try and combine the rocker switches with the relays to make the H-bridge and if it worked test it on an actuator. When I began building the system I came to the realization that I don t need to H-bridge for the two smaller actuators because the rocker switch has a high enough tolerance to handle the voltage and current. However I continued to build the system anyways for the sake of the larger, 23A, actuator. I did not want to use our actual wire and waste it so using alligator clips I was able to build half of the H-bridge and then just flipped the polarity of the actuator terminals to develop a full understanding of how the system would work. This system was using the voltage regulator designed as well so it was as realistic as possible. By activating the rocker switch in either direction is activated two of the relays in the bridge to move the actuator either up or down. I was happy with the above results and couldn t do much more with the actuator system without starting to mount to the frame, only problem is the frame isn t done yet. Therefore I moved onto powering the console with its voltage regulator and everything worked fine. I also went to Mansfield supply at some point to get wire, totaling $ I built the voltage regulator for the mini track; however the rest of the mini track has not been built yet. There are a few issues I m having with the mini-track at this point: tapping into the signal wire from the magnet sensor on the bike, programming the PIC16F877 with the code, because for some reason windows 7 won t work with MPLAB IDE and I don t have the authorization to use the SOE engineering computers, and designing a way to mount and ground all of the LEDs. This is one of the lower priority events at this point with the frame being top priority. At this point I focused on assisting Drew with the machining of the frame as things were finally starting to come together. The extensions and stabilizers had been dimensioned, cut, and welded together; however they are square ended and did not make very good contact with the current round stabilizers. Therefore I programmed a miller to cut a radius on each side to fit the stabilizer already on the frame. This allowed for welding of the extensions and stabilizers onto the frame in the front and rear, making this the longest stationary bike I have ever seen. I finished up this week by working on the timeline for an hour and a half which set up our future goals for the next few weeks.

4 Shane Tornifoglio Page 4 of 6 Finalized Console Voltage Regulator (12V to 3V) (correct pins)

5 Shane Tornifoglio Page 5 of 6 Finalized Rocker/Relay Voltage Regulator for Large Actuator (12V to 10.5V) (correct pins)

6 Shane Tornifoglio Page 6 of 6 Finalized mini-track with updated regulator (12V to 5V) (correct pins)