Posts tagged “community projects”
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At Pololu, I have spent the recent weeks developing new products, like the motor driver I announced on Wednesday, but at school (I am a mechanical engineering student at the University of Nevada, Las Vegas, UNLV) I have been managing an American Society of Mechanical Engineers (ASME) Student Design Competition (SDC) team. SDC teams create robotic devices to fulfill a problem statement that changes every year. They compete with their devices at one of ASME’s regional student conferences called E-Fests. Last year, I managed a three-member team that built The Rebel WIP and earned third place in the Robot Pentathalon at the E-Fest West. This year, my ten-member team made a squad of robots called The Rebel Bandits for the new SDC challenge, Robot Football. We overcame many technical challenges and 14 other teams to win first place at this year’s E-Fest West that competed this past Saturday!
The SDC’s Robot Football was loosely based on soccer, but with four robot teams competing to shoot eight tennis balls into four goals on a 5 m x 5 m field. Each team was assigned a goal to defend, and eight tennis balls were set in a square pattern at the center of the field for robots to score into the other goals. For this competition, teams could build multiple remote controlled robots, but the robots and controllers had to be able to fit inside a single 50 cm cube. Some teams built soccer squads with only two or three big robots, while other teams used up to six little robots for their squad (which made the matches super chaotic), but each team could only control one ball at a time. Robots controlling a ball needed to keep the ball on the ground when they moved around, but they could stop and lift the ball to shoot on a goal.
The Rebel Bandits.
I am really proud of the robots my team designed and built for this competition, so I want to share how my team made a first place robot squad! However, since we won the competition at E-Fest West, we were invited to compete again in the SDC Finals at ASME’s International Mechanical Engineering Congress and Exposition in Pittsburgh, Pennsylvania this November. We will be competing against the first and second place winners from the other student conferences: E-Fest East, E-Fest Asia Pacific, and E-Fest South America, as well as the SDC team from California State University, Northridge, who came in second place at E-Fest West. The teams will be more competitive, and the prize money increases significantly! So that makes me a little bit nervous about showing all the technical details for our robots right now, but I would still like to give a basic rundown.
Our strategy was to build three large robots: one defender, and two offensive robots. We call the defender robot The Outlaw. It is built on a U-shaped frame with 19 in (48.3 cm) long sides and has tall walls. Even though it cannot block from inside our penalty box and is not particularly fast, it can seriously impede the efforts of other teams to score on our goal just by being big and tall. The Outlaw uses three DC motors for its drive train at the base of the U-frame, and Pololu ball casters help support the far ends of the U-frame. One DC motor is driven by a G2 High-Power Motor Driver, and since we use an A-Star 32U4 SV for the Outlaw’s microcontroller, the other two DC motors are driven by a Dual G2 High-Power Motor Driver Shield for Arduino.
The Desperado and The Renegade.
The two offensive robots are named The Renegade and The Desperado (you should notice the Wild West theme by now). Other than the color schemes, these robots are almost complete duplicates. We decided to build only two offensive robots because it gave us sufficient space to build robust robots with high quality shooting mechanisms.
Each offensive robot uses four DC motors for the drive train. A standard size servo extends an arm with an intake belt, and a DC motor runs the intake belt to pull a ball into the robot’s reservoir. Another servo opens and closes a gate that keeps the ball in the reservoir or pushes the ball into the shooting mechanism. The reservoir allows the ball to roll on the ground as the robot moves without the intake belt constantly pushing down on the ball and impeding driving. The shooting device is a ramp and flywheel. When taking a shot on the goal, the operator stops the robot and the flywheel revs up to high speed. Then the gate servo pushes the ball into the ramp. The velocity of the wheel pulls the ball along the ramp structure and throws the ball at high velocity. Just beyond the outlet for the ball, a plate on a pivot controlled by a servo lets us control the ball’s trajectory. This allows us to shoot across long distances or over defender robots.
The offensive robots each use an Arduino Mega as their primary microcontroller. Most of the DC motors on The Renegade and The Desperado are controlled by either a Dual G2 High-Power Motor Driver Shield connected to the Arduino Mega or are driven by individual G2 High-Power Motor Drivers. On each robot, a Maestro servo controller is used as a slave controller that powers and controls the standard servos. Additionally we use the Maestros’ functionality as general I/O controllers to send logic signals to the individual 18v17 Motor Drivers. In our setups, we want the servos and the Maestros to be powered from 6 V, so we use a step-down voltage regulator to connect the Maestro power rails to main power supply on each robot, a 12 V lead-acid battery.
I am very fortunate to have worked with an awesome team this year for the SDC, and I am grateful for the parts and support we obtained from both Pololu and UNLV! It was also exciting to see different teams at the competition using other Pololu parts like our wheels, metal gearmotors, regulators, and brushed DC motor drivers. After our SDC Finals competition in November, I plan to write another blog post about more of the technical details of our robot. (Hopefully I will be able to brag a little about another first place trophy too!)
Patrick and 6 members of UNLV’s SDC team that traveled to competition in Pomona, California.
Until then, I want to know more about some of your projects! I hope you will share a little about your cool projects in the blog comments, or you can make a Pololu forum account and post in the Share Your Projects category!
Our favorite team of robot-making sisters over at Beatty Robotics has finished making another stellar robot! Their latest creation is a 1/10th scale functional replica of Curiosity, the rover from NASA’s Mars Science Laboratory mission. The rover uses a variety of Pololu products, both mechanical and electrical. For example, it uses a pair of G2 high power motor drivers to control six 25D mm gearmotors, each of which is coupled to a wheel with a 4mm hex adapter. The robot also features our voltage regulators, current sensors, logic level shifters, and pushbutton power switches. In addition to using our products, the rover also uses some stainless steel parts cut with our custom laser cutting service.
The Beattys are currently in the process of documenting their rover. Right now there’s a blog post out focused on the robot’s exterior, but the duo plans to also post about the electronics and functionality soon. We are looking forward to seeing more pictures and learning about how each part contributes to the whole system!
If you are curious to know more about the electronics inside of this replica rover, you can keep an eye on the Beatty website, or you can stay tuned to our blog – we will update you when they share more.
Erik Pettersson’s interactive sculpture, Roball, is a gripping take on the classic rolling marble kinetic sculpture. Roball uses a robotic arm to pick up a small ball and randomly place it on one of five tracks, where it twists and turns as it rolls down the track, eventually coming to rest at a holding station. The input to the system is a single pushbutton, and when the user presses the button, the arm picks the ball up wherever it stopped. Then, the device randomly selects another path, moves the marble to the start of that track, and releases it. A 12-channel Maestro controls the whole system and analog sensors (which might be our QTR-1A) at each holding station at the end of each track help not only detect the ball, but help the Maestro randomize its next move. Because of the ball’s non-uniform surface, the analog sensor will read different values depending on how the ball is positioned. That reading is then used in a calculation to determine what track to roll the ball on next.
You can learn more about this project on its Thingiverse page.
MIRR, which stands for Mobile Interactive Responsive Reflector, is an interactive installation that responds to people’s movement by independently rotating elements in its array of 98 mirrored panels. A FEETECH Mini Servo FT1117M actuates each panel and a total of five Mini Maestros control the servos. People can also use a custom box of arcade buttons to independently move each panel. You can read more about how MIRR works in this post on our forum.
A Maestro commands this Luftwaffe pilot to direct his steely-eyed gaze out into the wild blue yonder.
Klaus Herold, who makes RC models of World War II aircraft, used one of our Maestro servo controllers to elevate one of his German Luftwaffe models to new heights. A 6-channel Micro Maestro adds a touch of reality to his model by animating the movement of the head of the pilot. The movement has two degrees of freedom: the head rotates side to side and tilts up and down. Additionally, the cockpit canopy extends and retracts. You can see the pilot in action in the video below:
Laser cutting is an excellent way to make intricate parts for jewelry or decorations. These fantastic jewelry art pieces were designed by Melissa Cameron, an Australian-born artist based in Seattle, WA, who has work displayed in the collections of multiple art galleries, including the National Gallery of Australia. These pieces were cut from birch plywood and stainless steel using our laser cutting service. To get started on your own laser cutting project, submit a quote request here!
Pololu customer Yvon Hache made this 3D-printed aerial photography rig that he shared in a forum post. The rig, trailing 100 feet below the kite, automatically triggers a camera to take pictures at three tilt angles and sixteen pan angles. It incorporates an ARM Cortex-M4 microcontroller from Texas Instruments (32-bit, 80 MHz, TM4C123GH6PZ), an AltIMU-10 v5, Pololu voltage regulators, and a Zigbee module for wireless remote control. Yvon uses a pair of Pololu micro metal gearmotor extended brackets per motor—one mounts the motor to the frame and the other protects the encoder assembly.
More kite rig information and pictures can be found on Yvon’s website.
This summer, Jon and I participated in NASA’s nationwide Eclipse Ballooning Project with the University of Nevada. Specifically, we were members of the University of Nevada, Las Vegas (UNLV) section of Nevada’s team which also had a section from the University of Nevada Reno (UNR). Our goal was to make a payload to collect interesting video footage and scientific data, then fly that payload on a high-altitude balloon that would ascend to around 100,000 ft in the totality zone during the 2017 solar eclipse on August 21. Continued…
We were excited to hear from the NCA Lights high school student robotics team about their recent entry in the RoboFest Michigan Championship 2017 RoboHit competition. RoboFest is a series of robotics events and competitions organized by Lawrenece Technological University. This year’s baseball-themed competition, “RoboHit”, involved hitting a ping pong ball off of a water bottle with a pencil and circling the outer edge of the arena (base running).
The NCA Lights used a Zumo 32U4 Robot Kit and two 50:1 Micro Metal Gearmotors HPCB 6V with Extended Motor Shaft as the base of their robot.
Pololu customer Alvaro Villoslada made this impressive open-source 3D-printable hand prothesis. Each finger uses a 1000:1 Micro Metal Gearmotor HP 6V with Extended Motor Shaft to wind a fishing line—acting as a tendon—onto a spool. A magnetic encoder attached to each motor enables closed-loop control, and the motors are driven by DRV8838 DC motor driver carriers. An RC hobby servo controls the thumb position. Alvaro uses a Teensy 3.1 microcontroller to monitor the encoders and control the actuators, and he built a user interface in Python for controlling the hand from a computer.
For CAD files, detailed instructions and more pictures and videos, see the Hackaday project page.