VEX V5 - Gravity Rush - Lab 12 - Exploring Center of Gravity with the Robot

Materials Required:

Quantity	Materials Needed
2	VEX V5 Classroom Starter Kits (with up-to-date firmware)
1	Roll of Tape
1	Materials to make a Small Ramp (wood, cardboard, binders, etc.)
1	Meter Stick
1	Engineering Notebook

Step 1: Clearing a Space

A diagram showing a rectangular race track with dimensions labeled as 1.25 meters in height and 3 meters in length. The track has a solid black background with a green Start label on the left side and a checkered finish line on the right side. The word Finish is written in red next to the checkered line. The track represents a simple, straight course for a racing challenge — 3m x 1.25m racing track for the Claw Arm Challenge

The first step in creating a course for your V5 Clawbot is to clear a space on the floor approximately 3 meters (119 inches) by 1.25 meters (49 inches). This will be the racing track and allow two Clawbots to race side-by-side at the same time. Mark the space with tape or in some way so that the track is clearly marked with starting and finishing lines.

Teacher Tips

Locate a space that is 3 meters (119 inches) by 1.25 meters (49 inches). The track and ramp can be scaled down in cases where there is limited space, but the width of the track needs to be wide enough to accommodate two V5 Clawbots racing at the same time.
Promote the conscious development of cooperative learning skills by reviewing the Strategy and Teamwork (Google / .docx / .pdf) tips with students.
Gather materials for building the ramp in advance. There are recommended materials in the hardware/software section, but anything from three-ringed binders to plywood will suffice.

Step 2: Building a Ramp

A diagram showing two views of a wooden ramp structure. The top section of the image provides a top-down view, displaying a rectangular surface with three distinct sections. The height is labeled as 1.25 meters. Below the top-down view is a side view of the ramp, showing an incline on both ends with a flat section in the middle. The ramp is supported by vertical beams, and the side view illustrates the change in elevation from the ground up to the flat middle section — VEX V5 Clawbot going up a ramp

The next step is to build a ramp that is as wide as the course (approx. 1.25 meters or 49 inches). The ramp could be constructed using wood, cardboard, or anything available that is strong enough to hold the weight of the two V5 Clawbots. The ramp should have two slopes, first upward and then downward, and should be sloped gradually so that there aren't gaps at either end of it.

Step 3: Positioning the Ramp

A diagram of the 1.25 meter by 3 meter track from Step 1, with a ramp added, shown directly to the left of the checkered finish line. — 3m x 1.25m racing track with ramp

Move the ramp to the second half of the course. The ramp should be at least 1.5 meters (59 inches) from the starting line. Make sure the ramp is positioned so that its sides are precisely parallel to the sides of the track. In other words, make sure that the ramp is not crooked so that the V5 Clawbot's front wheels can reach the ramp at exactly the same time.

Step 4: Preparing the Robot

Power on the V5 Robot Brain, make sure it is paired with the V5 Controller, and run the Drive program on the V5 Robot Brain so that you’re able to wirelessly drive your robot with the V5 Controller.

Step 5: Running with a Resting Arm

A side view diagram of the Clawbot driving up an inclined wooden ramp. The ramp consists of three sections: an incline, a flat middle section, and another ramp leading down. The robot is positioned near the beginning of the ramp, with its front wheels on the incline and its back wheels still on the ground. The ramp is supported by vertical beams, and the robot appears to be moving upward along the ramp. — V5 Clawbot traveling the course with its arm all the way down

The V5 Clawbots should have their arms all the way down in the starting or resting position.

Teacher Tips

Check that the arm of each V5 Clawbot is lowered to the starting or resting position.
Group teams into pairs. During the first round, each pair will race the V5 Clawbots against each other.
Utilize a round robin bracket if there is an uneven number of teams.
Rotate the pairs after each round, if you have four or more teams. Ensure that the two fastest teams face each other in the next round, then the next two fastest, and so on.

Step 6: Running with an Angled Arm

A side view diagram showing a small robot with large wheels attempting to climb a wooden ramp. The robot is in the process of tilting backward, with a dashed line and arrow indicating a rotation of 25.5 cm. The ramp has an incline leading to a flat middle section and another incline leading down. The robot's front wheels are on the ramp, while its back wheels are on the ground, showing the difficulty of the Clawbot in maintaining balance on the incline — V5 Clawbot travelling the course with its arm angled out

During the second round, the new pairs will race their Clawbots again head-to-head.

In this round, each Clawbot's arm must be raised at least 25.5 centimeters (approx. 10 inches) above its starting position.

Teacher Tips

Check the position of each arm prior to each race to ensure the arm is properly positioned.
Notify students that the V5 Clawbot is prone to tipping when the claw arm is lifted (especially if the arm is raised and the claw is holding an object).

Step 7: Running with a Near-vertical Arm

A side view diagram showing a small robot with large wheels as it begins to tip backward while climbing a wooden ramp. The robot is leaning at a steep angle, with a dashed line and arrow indicating a rotation of 38 cm. The ramp consists of an incline leading to a flat middle section, supported by vertical beams. The robotâs front wheels are on the ramp while the back wheels are still on the ground, highlighting the robotâs instability as it ascends — V5 Clawbot travelling the course with its arm raised up

During the third round, the V5 Clawbots' arms must be raised 38 centimeters (approx. 15 inches) above its starting position.

If you have just two teams, the team who wins Round 3's matchup is the winner of the challenge.

Teacher Tips

Check the position of each arm prior to each race to ensure the arm is properly positioned.
Allow the winners of each matchup to continue to face off in another Round 3 match, until one team emerges as the overall winner.
Notify students that the V5 Clawbot is prone to tipping when the claw arm is lifted (especially if the arm is raised and the claw is holding an object).