Home - Team 05

    Mosquitoes have always been a major public health concern as these arthropods are responsible for transmitting a multitude of pathogen vectors such as the Zika, West Nile Virus, and Malaria. Modern researches have been made to combat these disease-carrying insects and have seen great efforts and results. UCSD's Laboratory for Eukaryotic Pathogenesis, Drug Discovery and Chemical Biology is in a continuous effort to understand how diseases are transmitted and how the transmission can be prevented. This research requires a large number of female mosquitos to be the subject of the experiment. Because only the females consume blood and are thus responsible for transmitting the virus, it is necessary to sort the male and female mosquitoes apart so that resources are spent on the more valuable female mosquitoes. 

     Before mosquitos turn into the flying adult, they spend a large part of their life in water, going through the life stage known as larva and pupa. Our design is centered around the Anopheles Stephensi mosquitoes that are primarily responsible for transmitting malaria. Their sexual dimorphism begins to appear in the pupae stage. However, this species of mosquito pupae have little variance in sexual dimorphism--the only distinction between the two is an appendage seen on the male pupae. Thus, it becomes a challenge for researchers to sort the two sexes. Currently, the lab sorts them manually under a microscope. With the completion of this project, the researchers can rely on automatic sorting and the manual work is reduced to placing pupae into the system.

Objective:

    Our team is tasked with designing a mechanical system to automate the sorting process of the Anopheles Stephensi mosquito pupae (and some stage 4 larvae). The goal is to separate the two sexes while maintaining a high accuracy rate and efficient timing. The sorting mechanism must be able to sort at least 1500 mosquito pupae per week with no hands-on assistance required other than turning it on and placing the samples. We must also not damage the female pupae, as they must be able to ingest blood at the end of their life cycle. Our goal is to eliminate the tedious process of hand-sorting mosquitoes to increase overall mosquito research efficiency in time and money.

Design Overview:

Final Design:

   With help from the research lab, we are able to design a system that works for genetically modified mosquito

pupae/larvae (similar to ones shown to the right) that contain fluorescent protein that will light up under a UV ray only in the male pupa's body. 

    We decide to use the color recognition method to classify the gender of the pupae and use a water circulation system to transport them onto different stages of the sorting process. 

    The flow chart above shows the final design of the sorting system.  A collection of pupae is poured into the funnel at the opening, they will then be carried through a clear, soft tube and into the revolving door by the downstream water. The revolving door stops the flow of the pupae/larvae for scanning. The camera takes the pupa image and the color detection software decides whether the fluorescent marker is present, then a signal is sent to the servo. The servo controls the centerpiece of the revolving door and rotates it to guide pupae/larvae downstream through the two out-leading tubes. The pupa will end up in one of the gender-specific sorting tanks. Lastly, a pump at each of the sorting tank takes water back to the funnel.