Ballistic Cart

Meg Chen

University of British Columbia

PHYS 420C (2024)

 

Overview

Materials

Design + Construction

Videos

Lesson Resources

Contact Me

 

Materials

Cart

 

A logo of a letter AI-generated content may be incorrect.

Train

 

A drawing of a cart AI-generated content may be incorrect.

Track

 

A black and pink rectangle with a white line AI-generated content may be incorrect.

List of Materials

A black and white image of a train AI-generated content may be incorrect.

(all the measurements are in millimeters)

A drawing of a cart AI-generated content may be incorrect.

(Please refer to this Onshape Design Link for more detailed dimensions)

Note: I chose to make my train rechargeable with adjustable speed, but feel free to modify it according to resources available. The demonstration should work if the train moves at constant velocity and has the dimensions specified for the wheel and the bumper (so that it moves in a straight line on the track and drags the cart)

 

-         Structure

-         Bumper (laser-cut with 3mm acrylic) -> so that the train moves in a straight line

A grey t-shaped tool AI-generated content may be incorrect.A drawing of a measuring device AI-generated content may be incorrect.

-         The bumper will be between the rails on the track, so the train's path is straight

A wooden box with wheels and a red tube on it AI-generated content may be incorrect.

-         Two main wheels (60mm diameter 3D printed) -> to be attached to the motors and drive the train

A circular object with a hole AI-generated content may be incorrect.

I used the wheels that came with the motor, cut the center part of each, then inserted them into my 3D printed wheel.

A yellow and black wheel AI-generated content may be incorrect.(image retrieved from amazon)

-         Two sub-wheels (50mm diameter 3D printed) -> to keep the train balanced

A grey button with a flower in the center AI-generated content may be incorrect.A grey circular object with a hole AI-generated content may be incorrect.

-         Rod (3mm diameter, 90mm long aluminum rod) -> to hold the sub-wheels

-         Train body (I laser-cut mine with 3mm plywood)

-         Lid and rim

A rectangular object with lines and numbers AI-generated content may be incorrect.

A blue rectangle with a black dot AI-generated content may be incorrect.

-         Base

A rectangular object with a number and a point AI-generated content may be incorrect.

-         Long side with opening for switch

A drawing of a rectangular object with numbers and lines AI-generated content may be incorrect.

-         Long side without opening for switch

A diagram of a rectangular object with numbers and lines AI-generated content may be incorrect.

-         Short side without opening for charging port

A blue square with black lines and a point AI-generated content may be incorrect.

-         Short side with opening for charging port

A blue square with black lines and a handle AI-generated content may be incorrect.A blue square with black dots and numbers AI-generated content may be incorrect.

-         Non-slip rubber carpet tape (cut into two 188.5 x 11 strips) -> to stick on main wheels to prevent slipping

-         Electronics

-         Charging port -> to recharge the Lithium battery

-         Since I chose to use a Lithium Battery, I used the TP4056 Lithium Charger Module with Type-C USB port, like the one shown below:

-         A close-up of a blue circuit board AI-generated content may be incorrect.(image retrieved from amazon)

-         DC-DC buck converter module (step-down voltage regulator) -> to adjust the speed of the train

-         I used this one:

A close-up of a blue circuit board AI-generated content may be incorrect.(image retrieved from amazon)

-         Switch -> to turn the train on and off

-         Two motors (200 rpm) -> so that the train moves at constant velocity

-         I used this one:

A small yellow electric motor with black and red wires AI-generated content may be incorrect.(Image retrieved from amazon)

-         One AA Lithium battery

-         Battery case for one AA battery

-         Heat shrinks tubing -> to safely insulate the wires

-         Solder and wire-> to connect the different components of the circuit together

TIPS:

1)    For the bumper, note that there are two pieces, please cut them separately and then attach them with hot glue

2)   The holes made for both the main wheels and the sub-wheels are made smaller intentionally, drill with electric drill where necessary to fit the rod and the motor connector part

3)    For the lid and the rim, I hot glued them together

4)   When laser-cutting the train body parts, be mindful about which side/orientation will be seen on the outside