Week 10/20 to 10/26

In this week, we determined to use the digital Hall Effect sensor to do test for scanning the corrugated metal strip. The test was very successful. In this case, we did not have to worry about the corrugated metal strip design. It is because if we try to use the analog output Hall Effect sensor to scan the corrugated metal strip and magnet, then the distance between two peak (up and up), the peak to peak distance(up and down) and the deflection on each curve has to be very accurate. It will be a very big challenge to make this strip. For now, we use digital Hall Effect sensor, the strip only need to focus on the accurate of the distance between two peak (up and up). The design will be shown below.

Week10/12 - 10/19

According to the bogie team and the track development team, the distance between the inner and the outer tacks is 2 in (50.8 mm). The width of the part of the bogie in between the two tracks is 33.5 mm. Thus the distance between the bogie and the track is about 0.5*(50.8-33.5) = 8.65 mm. The height of the magnetic switches on the bogie is 7.5mm from datasheet, and it will scratch the track while turning. Thus, the height of the peak for the corrugated metal strip is design as 5 mm. See Figure 1.

Figure 1 Space between Tracks

The ground came up with three kinds of corrugated metal strip we might be using. They are square wave, sinusoid wave and trapezoid wave corrugated metal strips (See figure 2). Square wave will be our first choice because the sudden change of height will allow the Hall Effect senor to have clear digital output. The distance between peaks (d) is depended on the speed of the podcar and the resolution of the data acquisition device, which is the Arduino board in the SuperWay project. The team have to find out the maximum speed of the podcar in order to find the minimum distance between peaks.

Figure 2 Designs for Shapes of Corrugated Metal Strip

Moreover, the team had decided to put the Hall Effect sensor on a ski which extent out of the bogie in order to keep proper distance between the corrugated metal strip and the sensor. The team is also looking for a magnet with proper size and magnetic strength.

week 10/05 to 10/11

In this this week, we tried to determine the size of the ferrous strip. According to the control team and the bogie team, the magnets detector on the bogie will be kept. Keeping the magnet detector will allow us to stay with digital ouput sensor. However, the magnet detectors are occupying too much sapce on the bogie, which became a problem for us to install the metal strip on the track. We came up with a proposing solution for this, that is to cut out the upper part of the magnet detector, and we will attach the corrugated metal strip just right above the position of the magnet detector. The upper part of the magnet dector is for placing the screws, but currently the detector are mounted using glue. Thus, the screw holes are no longer needed.

The team also examinize the track, and found that the distance between the two side of the tracks are different every where, it is a big problem for us to decide the size of the corrugated metal strip in this case.

We already found a nice size hall effect sensor. The rest thing depended on how small of the strip we can make.

Week 9/29 to 10/04

This week, it is because we have to prepare for our presentation, so we do not have that much time spend on our project.
Overall, our team tried to ask some workshop in San Francisco to make the ferrous strip this week. Unfortunately, none of them can make for us. It is because the ferrous strip we expect is the distance between peak to peak and the distance between upward peak and downward peak have to be very accuracy. Probably, we have to ask help from some more workshops or companies in the coming week.
Moreover, we will test the new hall sensor in the coming week.

We also found some of the small bussiness websites which might be able to manufacture the corrugated metal strip we want, and we will contact them for more information.

http://www.builders-in-scale.com/bis/parts-metal.html
https://www.mechanicalmetals.com/accessory-items/foam-closure-strips-and-plugs/