Put Together–Connecting the light-sensing circuit to the flashing light circuit
By Jianqiao Xiao
This week I tried to connect the light-detecting circuit to the flashing light circuit to make a prototype of the final product. It is quite easy to do this work since I need to just connect the output of the light-detecting circuit to the input of the inverter of the flasing light. The way I connect the circuit is depicte as below
And the real circuit looks like the one shown below
It seemed that everything goes well so far until I powered the circuit. Even though I have duty cycle controlled through the diode-resistor cicuit, the duty cycle of the light was out of control–the light flashed unexpectedly and changes its duty cycle every time I power the circuit. In addition, the light is pretty dim and hard to see at night. These two drawbacks would really hurt our product.
As I have just learnt the usage of transistor (BJT) I think it would be a good way to apply the transistor to the circuit and separate the controlling circuit from the power circuit. In that way, not only wouldn't the brightness of the light be affected by the controlling circuit, but also make it easier to change the working voltage of the light if we change the type of light we use.
Automated switch to detect when the rider is on the bike
By Kausik Venkat and Yupeng Yang
We do not have too many updates from this week. We did further research on the parts we considered last week and decided to pursue both the pressure sensor and the vibration sensor.
We think the vibration sensor will be more accurate as it can tell when the bike is in motion but based on the vibration sensors we have found online, we cannot identify how to attach it to our bike.
We also feel pressure sensors would be a good option because it can be placed under the seat and we will be able to tell that a rider is on the bike during stop signals, which means that we do not need to create a delay in the system because we assume the biker is always on the bike during his or her trip, whether the biker is in motion or comes to a stop.
