Easel 5000 Week 5 Group Report February 24, 2006 Alison Biercevicz Seth Novoson Justin YuWork Completed Research Additional LED research was done to solidify concepts for the mounting of the system. Considerations like LED light intensity and eye safety were looked into. Also operating life was investigated to make sure the LEDs would last as long as possible. 100,000 hours seemed to be the general rule of thumb for most of the sources I investigated. Also precautions for the actual mounting process were looked into. Lead forming, mounting method, and temperature limits for soldering were really important topics to look into. Also the safety factor of heat dissipation was considered. Contacts Professor Northorp was again contacted to discuss a simplified circuit. The previous dimming option was found to be ineffective so a new schematic with that taken into account was drawn up. Additional calculations were done to make sure the hfe of the transistor was not exceeded. Patty Mitchell was once again contacted to inquire about the current painting system Tom is using. This is crucial in order to avoid mistakes that have already been made. LED System LED mounting options were drawn up. Dimensions were put together for multiple options for the LED light mount. It has been decided that an elongated box will be used to mount the LED system. The LEDs will be mounted inside and an clear plastic PVC sheet will be used to cover them up and protect them from mechanical damage. One box will be constructed out of aluminum and one will be constructed out of white PVC and they will be compared to see which is better when considering weight and functionality. The friction hinges were received for the easel frame and for the light box. The simplified circuit has had the parallel resistors from the LED portion of the circuit removed and replaced with a single resistor right before the LM555 chip. This will be tested with a potentiometer to attempt dimming yet again. Also the battery connector was found in stock at a local Radio shack and will be picked up as soon as the battery arrives to make sure it is the right connection.Machine Shop Work This week, more machining was done. Because of a change in measurements one of the pieces intended to join the easel canvas holder in place needed to be recut and drilled. LED system cover Preliminary LED casing options were explored and it was decided that two options would be built. The first option will be constructed of PVC, and the second will potentially be built out of aluminum. The first option was done this week. With the help of Serge, the PVC was cut with a large saw at the machine shop and the basic dimensioning was done. The shearing cutter was also used to trim the clear plastic that will protect the LEDs. Canvas Holder Design Last week, it was revealed to us that the artist using this easel would be painting extensively on sheet metal pieces with dimensions in the range of 9"x36". Upon discussion and research into this, it was decided that the current design of the canvas holder and the easel in general would be able to support this size canvas. No further changes to design will be necessary.3.6 V100 ohms24 ma3.6 V324876513.476 Kohms22Kohms51 Kohms.01 uf.01 ufLM5559 V Figure 5.1 - LM555 Circuit Dampening The shipment from Reell Corporation came in. Now that there are friction hinges, dampening for the easel system is incorporated into the design. Each dynamic joint will have friction hinges attached to them so that when adjusting the position of the canvas or any of the arms, there will be a higher required force to move the joint. This prevents many accidents and hazards the artist or aids may experience in using the easel. Future Work Next week the LED system will start its final mounting preparation. The components of the LED light box, actual LED mount and the circuit will be wired. The soldering and such will follow the preliminary set up of the circuit to ensure that everything is in working order. The hinges that were just received will be applied to the design. This may prove to be a large challenge.Project Review We are still on good track. All of the parts of the easel have been staged and at this point we are waiting on some parts to make any further progress. A good portion of the construction and machining has been done. We should still have ample time to complete construction and then do product testing. Incorporating the friction hinges into the joints will require a lot of trial and error to see what works best and will be the focus of next week. In addition any problems that crop up in the initial product trials will be addressed in the coming weeks.Pictures Figure 5.2 – Seth using the shear cutter Figure 5.3 – Justin measuring the PVCFigure 5.4 – Machine used to cut the PVC Figure 5.5 – Cut PVC piecesHours Worked Alison Biercevicz - 12 hours Seth Novoson – 10 hours Justin Yu -11
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