Author: Terrence Tu

Introduction:

In the lab with Professor Danyang, we aimed to observe the difference of the circadian rhythms between regular drosophila and mutated drosophila. We are expected to see a clear circadian rhythm on regular drosophila while no such rhythm is observed on drosophila with genetic mutation.  

Procedure:

1. We got two different types of drosophila in two culture vials. Regular ones are in the pink label vial and mutated ones are in yellow label vial (if I remember that correct). First we need to use CO2 anesthetizer to temporally immobilize flies.

Once drosophila is immobilized,  it will fall to the bottom of the vial.

2. Open vials and pour all drosophila on the Flowbuddy CO2 system to keep them all anesthetic. Then we need to pick male drosophila out, put each of them individually into a fly behavior monitor vial and label the vials. The reason why we do this is that drosophila has a very short life cycle so that female drosophila may lay eggs in the vial, thus affecting the accuracy of the experiment. Thus, we will only use male drosophila in the whole experiment. 

Seal one end with food and the other end with cotton, so that we can keep the drosophila alive with enough food and oxygen. Vials with yellow label are regular ones. Vials with red label are mutated ones. 8 of each and 16 in total.

3. Put all the vials on the monitor and put the monitor in a total dark environment. In this way, we can see that, if the regular drosophila does have a circadian rhythms, their locomotion will show a pattern in each 24 hours even when they cannot tell the day or night. The monitor will record how many times they fly across the middle of the vial every hour.

  

Data Analysis:

After I got the data from Professor Danyang, I figure out that the experiment I conducts almost failed. Among all 16 samples, only 5 survived from the process above. 4 of them are regular drosophila and only 1 of them is mutated drosophila. Unfortunately, 2 of the 5 drosophila lost readings in the half of the 8-day process. All of the rest 3 drosophila are regular drosophila. The sample is too small, which means I can barely get anything useful from it. But anyway I deal with the data of these 5 drosophila and see if there is anything I can get.

From 16:00 on 14 April, I turn every 24 hours in to a day with only 22 hours on the last day. The x axis is the point of time and y axis is the how many times they fly across the middle of the vial. In this way, I turn the data of each drosophila into a line chart.

Regular drosophila number 9. Survive all 8 days. However, the drosophila shows no circadian rhythms at all on these 8 days.

 

Regular drosophila number 11. Survive all 8 days. Show a rather clear circadian rhythm. It was extremely active during the period of 6:00-8:00 of everyday and relatively inactive from 3:00-5:00 and 9:00-16:00 of everyday. In period of 17:00-2:00, it status was quiet fluctuated.

Regular drosophila number 16. Survive all 8 days. I would argue it has a clear circadian rhythm. During the period of 20:00-11:00, it was active. In the rest of the day, it was inactive.

Regular drosophila number 14. Died in day 6. It has a similar circadian rhythm as the number 16 and the frequency is as high as number 16 until one day before it dies.

Mutated drosophila number 7. Died in day 4. I don’t see clear circadian from it. The data size is too small. 

Conclusion:

To conclude on the experiment, from this limited-sized sample, I would argue that circadian rhythms does existed on regular drosophila, even the sample size is really too small, and I will not make any conclusion on mutated drosophila since I got nothing about it from the experiment. 

However, from the process, I can imagine the how difficult the scientific community approaches these results. To prove the conclusion of the experiment, scientists need to conduct a much large sample size experiment and it mush be extremely time-consuming. Moreover, raising the idea is much harder than doing the experiment. The complete experiment we are doing nowadays may be based on a process of repeated corrections. Similarly developing robot and software cannot be trouble-free. However, we will finally achieve what we want if we keep going.

After spending tons of time on figuring out how to arrange loops in loops, Justin and I realized the complexity of our previous project is far beyond our imagination and capability. We do not want present unfinished product for our midterm project. Thus we decide to switch to another project. In this way, we can at least show a complete work at the presentation.

In the new project, we tried to imitate territorial behavior of some animals. One of the most typical territorial animal is tiger. The following video shows how tigers fight for territory. 

Basically we are going to imitate the behavior through remote control. One micro:bit will work as controller and control our tigerbot from distance. The tigerbot can make movement, give out sound of threatening and fearing under control. We achieve the coding part through the MakeCode. 

Code for Controller:

Code for Tigerbot:

Display of Movement Function:

Micro:bit has built-in acceleration sensors. It can sensor the change of g on different axis.  Through inclining micro:bit, we can change g on different axis. Once acceleration sensors sense these changes, the controller micro:bit will send out signal through radio function. The micro:bit on tigerbot will receive the signal and move the tigerbot.

Display of giving out sound of threatening and fearing:

By pressing button A and B on the controller micro:bit, we can control the tigerbot to give out different sounds.

Sound of threatening:

Sound of fearing:

Remarks:

1. The new project still has a lot of places for improvement. For example, all the actions of tigerbot is controlled by us. We may write code to calculate the rate of hurt and give out sound of fearing automatically in the further project. 

2. The previous project is not totally abandoned. We have kept what we achieved so far and it might be used in the future projects.

Basically Justin and I will do the same thing I post in my last week’s lab report. Two Kittenbots will imitate ants’ food gathering behavior. Ant is almost blind, thus it searches food through its sense of touch. Once it finds food, it will go back to its cave and leave pheromone on its way back. Then other ants will follow the pheromone to find food. For simplicity, we will use a large paper panel to build a six-route plane. Two ants will search each route. Once one ant finds food. The other ant will stop and turn back to the start point. Then it will go straight to the route with food. There are schematic diagrams in my last week’s report, thus I will not copy them here.

Note: We will first separate our whole project into small parts and use Makecode to realize these small parts. But our final work will be based on python.

Source: https://www.quora.com/How-do-ants-sense-food We basically design our project according to the link above.

Justin and I try to build a kind of vehicle which imitates ants’ food gathering behavior. Ant is almost blind, thus it searches food through its sense of touch. Once it finds food, it will go back to its cave and leave hormone on its way back. Then other ants will follow the hormone to find food.

For simplicity, we will use a large paper panel to build a six-route plane. Two ants will search each route. Once one ant finds food. The other ant will stop and turn back to the start point. Then it will go straight to the route with food. Schematic diagrams are showed below.

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Remarks: It is our very first proposal. Thus the steps may change due to limitations of our capability and practical effect.

1 . Plan

On start, Justin and I tried to build a reverse version of the shadow-fearing robot, which is a light fearing robot. When the vehicle is set down in a dark or dim room, it drives straight forward until the light sensor senses high intensity light. Then left motor of the vehicle will stop. In this way, the vehicle will veer. It will start turning again until the light sensor no longer sense high intensity light. However, when will try to achieve this behavior by using python, we find out there is no code for calling the light sensor in the library. Another way of achieving this behavior through python is using external sensors, but it is beyond our capability. 

Thus, we decide to try to achieve another behavior, which is wall follower. However, since we don’t have whisker brick, we have to redesign the logic of the behavior by replacing whisker brick with microwave unit. But we found out that it needs at least two microwave unit to realize the behavior. We have to give up this plan.

After spending most of time with achieving nothing, we decided to at least make something. Thus we decided to use MakeCode to achieve the shadow seeker behavior. The main part we used is Line Follower Unit. We interpret the black line as shadow and the vehicle will automatically drive on the black line. 

2 . The completed code is shown below.

3. Implementation

4. Something more

After doing some research, I find out the Kittenbot to some extent is a small version of sweeping robot. Modern sweeping robots usually have microwave sensors or  infrared sensors, a basic part of line follower unit, to sense obstacles and veer. It is interesting to see that these robots with very simple behaviors have already become an important part of our daily life.

It enlightens me that I may combine the microwave unit and line follower unit to conduct some more complicated behaviors. However, only several pins have read function. Most ones only can write. I may have to give up some functions of these units. Thus, how should I implement complicated behaviors needs more thinking.