IGVC Mechanical 2014
Contents
Tasks
Development
- Autodesk Inventor
- We model our robot in Autodesk Inventor, and perform FEA with the inbuilt stress analysis tools.
Structure
Our robot frame consists of primarily 1" steel tubing that has been custom designed and welded in-house. Steel tubing is chosen largely for its rigidity, with design emphasis on ruggedness and high payload capabilities, similar to that seen in military environments. The frame provides partitions for electronics, motors and sensors.
Suspension
Much emphasis has been placed into the design of the robot's suspension. The primary objectives of off-road capability and vibration damping (for sensors) have been achieved by allowing for independent suspension for each wheel. The robot sports 4 ATV wheels and heavy-duty shock absorbers, allowing it to traverse rough terrains at high speeds while damping residual and transient vibrations to the sensors and giving each wheel up to 5 inches of vertical travel.
Drivetrain
The vehicle utilizes skid-steer mechanics by mechanically linking the wheels on each side of the robot. This is accomplished via a central motor and gearbox per side with two separate outputs, one going to the front and back wheels. The sprockets and gearbox give a combined reduction of 30 to 1. This coupled with the two 4.5 HP Ampflow motors ensures that the robot will not get bogged down in muddy or rocky terrain. Additionally, this allows for a top speed upwards of 20 MPH to be achieved.
Weatherproofing
Heavy emphasis is placed on making the robot resistant to weather. The custom-machined gearboxes are sealed shut and snap-on body panels cover the entirety of the robot to keep water from directly seeping in. Additionally, water run-off flaps are attached to all sides of the body panels. Splash guards are also employed to keep water and debris thrown from the wheels from entering the region with the motor controllers and other electronics.
The button panel and electronics mounted on the mast also reside in weather resistant enclosures.
Other things
The robots sports a variety of features that make it easy to maintain and operate. The body panels are easily removed via thumbscrews from any location, providing easy access to anywhere on the robot.
Emphasis is also being placed on ensuring ease of testing and transportation of the robot. Basic design parameters have been adhered to, such as making the width of the vehicle fits through a standard doorway and making vehicle such that the overall height fits with the transportation trailer.
