Construction

The idea for this project was conceived from two group members involved at the CWU campus. The analysis, design, manufacturing, and testing are also completed within the restraints of the CWU campus build and design facilities.

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            The suspension consists of multiple parts that are fabricated using the available equipment at the CWU MET department in the machine lab and foundry. The remaining parts for the suspension are purchased from a third party and will be used in relation to the machined parts. These parts consist of all springs, pins, tires and shock absorbers associated with the suspension.

The suspension is a compact design in which the shock absorbers are able to support the frame and drive train. The first component of the suspension is the control arms. The control arms calculations and drawings can be found in the appendix. Control arms are hinged suspension linked between the suspension arm connector and the suspension hub that connects to the wheels. The suspension arm connector of the control arm is attached by a single pivot, using a pressed fit rod that is clipped on each end. Directly connected to the suspension arms on the other side is the hub.The hub is the central part of a wheel that rotates with the axle and from that the axial rotates. In my design the shock absorbers will be directly connected to the control arms. The shock absorbers are devices that absorb jolts and vibrations especially on a motorized vehicle. The shock absorbers should absorb 40% of deflections. Based on my calculations the shock absorbers will be able to support a drop from 2 feet.

During the manufacturing process of the suspension our team did run into a few bad spots. The RC car does sit lower then we had hoped for and could become a problem while driving over hills and rough terrain. In order to solve this problem, we will create a bracket that can be bolted to the top of the shock mount, so the shock absorbers connect higher up. The turnbuckles will be lowered down so they connect on the inside of the rear shock mount above the axle. This will benefit the turnbuckles because they would no longer have an angle in the horizontal direction and would be parallel to the axle. This would give the turnbuckles more control. The tires would then be affected by this and would create a better alignment.

Steering Mechanism

The steering assembly consists of a servo motor that mates with a steering rod that is parallel to the axle. The steering rod is offset from the axle using the Ackermann steering principle and interacts with steering arms. The steering arms are angled to provide non-slip turning and not interfere with the axle. The servo motor uses a spindle like wheel to move the steering rod laterally left to right. The steering rod is machined from 6061 aluminum flat bar stock and machined with the manual mill and drill press. With one hole in the middle of the bar and one on the servo wheel, a pin loosely mates with the two. Having the pin loose, allows for the steering rod to move back and forth without binding.

In the manufacturing process the above assembly did not function. Another assembly was thought of having two steering rods and connecting them to the servo itself using a small thick wire and small bushings. The ends of the steering rods connect directly to the servo arm on the outside.

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The frame consists of a flat piece of material. The frame connects all objects and is the main part of the RC car. The frame is made of 6061 aluminum because it is light weight. The frame has many holes so other objects can screw into it. The frame will also be made to be as light as possible.

About Body