Phase 2 Update:

The following stages include more System Engineering and less conceptual design work. The team will begin implementing 2nd round concept feedback, while placing a larger emphasis on viable system designs in the coming month. The first requirement when building the system is determining specifications developed from Phase 2 Analysis, and sourcing the appropriate pump for our product.

When Dealing with a negative pressure control unit the team was tasked with deciding whether a vacuum pump (pictured right) or peristaltic pump (pictured left) was best to suite design needs. The team ultimately decided with the adviser that a peristaltic pump would achieve what the team desired. The reasons for this are as follows.

Given that the team decided to move forward with an extremely lightweight device. Any amount of pressure applied to the skin besides the physical device resting on the skin can drastically change data output. With a vacuum pump, a proper seal and pressure can be acquired which is ideal; however, a vacuum pump does not continue to run, but rather creates a stand alone chamber. This would require the team to place the lightweight device on skin and hold the device in place until the pump is turned on and a proper seal has been developed. This poses a detrimental effect to data given our device only weighs 3 grams and the average pressure of someone touching skin can far exceed this.

With a Peristaltic Pump the device continually runs as it has entry and exit tubing, and dispenses air through a stand alone chamber. This allows the device to be placed and sealed under its own work. Picture similar to a magnet as approaching another opposite sided magnet and attracting itself once it is close enough. The cup and probe will attach itself to skin as the device closely approaches skin.

The next obstacle is determining pump specifications. Solidworks modeling has led to desired pressures for the system; however, all pumps are measured in volumetric flow rate (mL/min). These are issues that will be resolved in the next two weeks, and the next blog will greatly detail the technical analysis behind the system and pump specifications!