3! – Prototype II Final Report: Mechanical Camera Control System for Wheelchair

Introduction:

This project is a mechanical control system for people who have trouble using their hands and use a wheelchair. People with disabilities, who are using wheelchairs, often have trouble using a camera to take pictures or videos. It is hard for them to hold the camera steady and take shots at the same time. A camera is a way they can capture  memories of their lives, and save them to share with others. This project will allow them to position and use a camera easily and effectively without any assistance. We used a turntable for the rotation of camera (panning), two servos for pitch movement and pan movement, one arduino uno board, one joystick, structures and supports from plexiglass. 

     In comparison to the first prototype, we used gears for 360 degree rotation of the platform instead of the limited rotational movement that a servo arm gave the first prototype. Our joystick control system was not able to hold a fixed position in pitch, which we fixed in prototype II by improving our arduino codes. The overall structure of this prototype is also smaller compared to the earlier one.

Description:

The mechanical design includes a base where camera can be mounted on a rotating platform. The control system is able to tilt and pan the camera. The top platform will spin a full 360 degrees, so that clients can take a picture of themselves, or show a picture to others once they take it. The whole base will also move up and down, raising the position of the camera. Clients will be able to control the position of the camera and once it is set, they can manually control the interface of the camera. This feature will aid them in taking shots in less time and will also solve the problem of lifting the weight of the camera and aiming it.

The initial ideas about our prototypy II design are given below:

  • Joystick which could be mounted on the wheelchair so we need a clip attached on the joystick.
  • Vertical stand for the camera which is mounted on the wheelchair. The vertical shaft of the MCCS can go up and down, and the fixed platform is connected to top of this vertical shaft.
  • The camera platform has a hinge allow pitch motion of the camera and is mounted on the rotating platform. There will be a fixed platform underneath the rotating platform.
  • Use three servos to control the position of the camera mounted as shown in the picture.
  • Joystick and servos will be connected to Arduino board so that they can communicate with each other.
  • Adruino, servos, circuit board and wires are will be inside the plexiglass box.
  • All platforms will be made from plexiglass.

we started by building the box that hold the servo and circuit board from plexiglass. Then, we designed and cut the rotating platform from plexiglass, using a 2-D computer controlled laser cutter. Then, we moved to the platform that holds the camera and built it as shown in the diagram below. after that we started working on the programing for the movement (rotation 360 degrees and pitch +/- 30 degrees). The last part was adjusting the length of the arm that controls the pitch movement. In every step of our design, we used hot glue, so that we could fix any mistakes that we made. After we made sure everything was working as we wanted, we started using cement glue for the plexi glass. The arduino code for our design is at the link: 3! Design I code. The schematic diagram, and pictures of our final design are below.

Diagrams:

Reflection:

For the prototype II, we managed to rebuild our initial design and made it more durable and functional, using plexiglass. We managed to add 360 degrees movement  by using a gear train to rotate the platform. We have learned a lot in constructing this prototype, and now we have a vision for the way ahead and how we are going to tackle it. We believe that we spent too much time designing and cutting plexiglass, but eventually we got it done. Our plan for the next semester is to have a up and down movement and with wireless control system. If possible, we would like to add remote control for the camera shutter and other camera functions ( mode, flash, focus, zoom, etc. ). We will focus more on electronic section of the project to improvise the control system and make it easier and effective for the users to control the camera. We were unable to complete the up down movement of the design which has been challenging to us. We are ready to face the problems that we have encountered so far and complete the project that we have been working on.