Our process of building a physical robot prototype

田家煒

Idea

Due to the boost of Technology these days ，people are carrying less and less things while going out，the purpose of our project is to allow you to carry nothing when shopping，even you don??t have to go out of your house.A car which youcould control from Wechat/follow you automaticly with a scissorlift and a box to fill your need with carrying objects.The phone is placed at the top and designed to help you out with the QR codes with a press of button.

After a bit of discussion we made a blueprint of our project?±s prototype.We chose a metal robot with control device as the base，as we made a box of cardboard which were first joined to the robot by a subordinate box which fits exactly the same size of the robot by velcros.But soon we realized that they??re not stable and balanced as there will be some amount of weight on it.So instead of that，after a discussion with the professor，we simply screwed it onto the robot，for it was brought together by them and there are empty spaces for extra ones.Due to our original thought，we used to make a remote control part onto it and when we saw our limited time to the deadline，we just programmed it to go on a fixed line.For the other part，we first decided to 3D print the rest of the parts，but considering efficiency and convinience，we end up using cardboard to make the rest with only one side of the original scissor lift.We used hubs of Fidget Spinners to join the parts.Then we found a problem：there are balance problems with the top part.Since we are having this we decided to have a lift on both sides，With the experience of the last one，we quickly built the lift，then a another situation came：cardboards is not strong enough to hold the top bit，then we used pencils to give extra strength，successfully reduced the leaning as preventing the movements.Eventually，we compromised to truncate the lift to half of its length.

Then we found another problem：How do we connect them？We connected these by a roll of paper which are glued to the hubs，therefore preventing us from adding more things to connect both side??s lift.Then we heard about that the laser cutter is arriving，so we constantly made a decision：cut them out of wood for precision and strength.Due to the high efficiency of the machine which we were told，we then tried to get the remote control back，but since then we could not connect the robot and load code to it，we were forced to give up this idea.Then after a weekend，our robot suffered a severe damage which we don??t know who done it：half of the wheels were teared apartthoroughly and the screw could not be screwed on ever since.However，we managed to use the hot glue to fix this problem，but after we launched it on，we found out that it??s too unstable for running.Nevertheless，we are lucky to have substitute parts which are not damaged and they really saved our project.Then there comes a good news：the laser cutter arrived！We are also honored to use it the first time since it arrived.The results were perfect！Although is much more heavier than cardboards，but zhe two sides of the wooden version is identical thus they are much more stronger.We put it on to the trail that we designed，then there came a problem：the size of the wooden stick does not fit in，the hubs were not long enough to fit it either.After a talk，we created two wheel-shaped piece of wood to keep the stick in.Then is the wiring and coding，according to the example given in the kit，we easily got one of the servos working but it was not strong enough to lift the whole thing.Thus we want to connect the other one and make it working，we added an extra board，connected 5V to it then we could have two 5Vs so both of them are working.Then there came another problem：the lift is way too heavy for the servos that we were using，we tried tape，oil to reduce the fraction but it does not work.

For the future plan by 2023，we want our product to be an automatic robot which follows its owner or to be remotely controlled by Wechat from 100m or so.There are three control buttons physically on the robot/digitally in the Wechat：one for lifting up and down，one for automaticly following or not，the other for displaying a QR paying code. The box will be big enough to fill in a lot of things ，a really strong laser sensor，at last a strong servo on a metal scissorlift.