Archive for May 2013

Third & Final Design

The third design of the project was created following new instructions, the main objective was shifted towards creating a pan & tilt devices. Also trying to resolve the issue that was found in prototype two; the M1 from schematics 2-1 of the second design. It will either be set in front of M0, which would required a worm gear set to change the direction of motion, or the M1 will have to be placed in one of the sides, disproportioning the device’s arm, see image below.

Prototype II 180º

Mechanical design III

This design is trying to solve the issues encountered in the last two designs and trying to develop the device that would be used for pan & tilt movement. It could still be used for testing devices if required by implementing the algorithm in the microcontroller. The device will have the same number of actuators as it can be appreciated in schematics 2-2. M1 and M2 have changed their position to reduce the distance of the arm L1 and facilitate the two axes movement. M0 will rotate the base creating 360º of movement (pan) and M1 will rotate the gripper 180º (tilt). For the project, 3mm thick black Perspex will be used and will be cut in the laser cutter.

P&T Devices1P&T Devices2P&T Devices3

P&T Devices CADP&T Devices1 cad2

The prototype from design I and design II were created using thin cardboard and the models required some adjustments since was less than 3mm thick. Image above shows the final prototype. In the top right image, it can be appreciated the attachment added to the gripper to hold a small webcam.

 

Base of Prototype III

The base of the device will hold the circuit for control and power supply; ideally, it will have a single PCB containing all the necessary components. Two levels containing different parts of the circuit were used instead, as seen in image on the left.

  • Level one; contains the microcontroller PCB for testing.
  • Level two; contains the power supplier and two stepper motor drivers.