rover

99 Articles

A Mechanical Edge-Avoiding Robot

December 27, 2020 by 19 Comments

In the age of cheap sensors and microcontrollers, it’s easy to forget that there might be very simple mechanical solutions to a problem. [gzumwalt]’s 3D printed mechanical edge avoiding robot is a beautifully  elegant example of this.

The only electric components on this robot is a small geared DC motor and a LiPo battery. The motor drives a shaft fixed to a wheel on one side, while the opposite wheel is free-spinning. A third wheel is mounted perpendicular to the other two in the center of the robot, and is driven from the shaft by a bevel gear. The third wheel is lifted off the surface by a pair of conical wheels on a pivoting axle. When one of these conical wheels go over the edge of whatever surface it’s driving on, it lowers front and brings the third wheel into contact with the surface, spinning the robot around until both front wheels are back on the surface.

Mechanical alternatives for electronic systems are easily overlooked, but are often more reliable and rugged in hostile environments. NASA is looking at sending a rover to Venus, but with surface temperatures in excess of 450 °C and atmospheric pressure 92 times that of Earth, conventional electronics won’t survive. Earlier in the year NASA ran a design competition for a completely mechanical obstacle detection system for use on Venus.

[gzumwalt] is a very prolific designer on ingenious 3D printed mechanical devices. This mechanism could also be integrated in his walking fridge rover to explore the front of your fridge without falling off. Continue reading “A Mechanical Edge-Avoiding Robot” →

Incredible Discrete MOSFET Rover Has Maximum Blink

December 4, 2020 by 12 Comments

What do you get when you stick 1738 MOSFETs together? If your answer was a ‘4-bit CPU’, you would be totally correct. Available as a product over at Marutsu as the ‘CPU1738’, it seems to target beginners to computer theory, with build instructions that explain how the CPU is built up from individual MOSFETs that are combined into logic gates.

A CPU1738 NAND PCB.

While decidedly more compact in its SMD format than it would have been with pure through-hole parts, the use of countless small PCBs on top of the larger PCBs make for a pretty hefty package. Board after board build up the CPU, and the assembly continues with the addition of sensors, motors, and wheels. In the end, a robot emerges, albeit a somewhat wobbly-looking one.

Check out the video linked after the break, though before starting one up, note the 50,000 Yen (approximately $500) price tag for the CPU block alone. On the other hand, in addition to the 1738 MOSFETs, there are also 1070 LEDs, so you get what you pay for in blinkies.

Continue reading “Incredible Discrete MOSFET Rover Has Maximum Blink” →

Sending 3D Printed Parts To Mars: A Look Inside JPL’s Additive Manufacturing Center

November 10, 2020 by 5 Comments

With the Mars 2020 mission now past the halfway point between Earth and its destination, NASA’s Jet Propulsion Lab recently released a couple of stories about the 3D-printed parts that made it aboard the Perseverance rover. Tucked into its aeroshell and ready for its high-stakes ride to the Martian surface, Perseverance sports eleven separate parts that we created with additive manufacturing. It’s not the first time a spacecraft has flown with parts made with additive manufacturing technique, but it is the first time JPL has created a vehicle with so many printed parts.

To take a closer look at what 3D-printing for spaceflight-qualified components looks like, and to probe a little into the rationale for additive versus traditional subtractive manufacturing techniques, I reached out to JPL and was put in touch with Andre Pate, Additive Manufacturing Group Lead, and Michael Schein, lead engineer on one of the mission’s main scientific instruments. They both graciously gave me time to ask questions and geek out on all the cool stuff going on at JPL in terms of additive manufacturing, and to find out what the future holds for 3D-printing and spaceflight.

Continue reading “Sending 3D Printed Parts To Mars: A Look Inside JPL’s Additive Manufacturing Center” →

Robot Travels The World

October 17, 2020 by 7 Comments

Around the World in 80 Days may have been an impressive feat of international travel in a world before widespread air transit. In modern times though, it’s not even necessary to leave your home in order to travel around the world. To that end, [Norbert] is attempting to accomplish this journey using a robot that will do the traveling for him as part of this year’s Virtual Maker Faire.

The robot is called the World Tour Robot, and the idea for it is to be small enough to ship to each new location around the world and be simple enough to be repaired easily. It is driven by two servo motors and controlled by a Raspberry Pi which also handles a small camera. Once at its location, it can connect to the internet and then be able to be controlled through a web interface. Locations are selected by application, and the robot is either handed off to the next person in the chain or put back in a box to be shipped.

The robot hasn’t left for its maiden voyage just yet but [Norbert] plans to get it started soon. Hopefully there are enough interesting places for this robot to explore on its trip around the world, although it’s probably best to avoid Philadelphia as it is known to be unfriendly to robots.

Modular Rover Platform Rolls On 3D Printed Flexible Tank Tracks

October 11, 2020 by 12 Comments

Master of 3D printed robots, [James Bruton], plans to do some autonomous rover projects in the future, but first, he needed a modular rover platform. Everything is cooler with tank tracks, so he built a rover with flexible interlocking track sections.

The track sections are printed with flexible Ninjaflex filament. Each section has a tab designed to slot through two neighboring pieces. The ends of the tabs stick through on the inside of the track fit into slots on the drive wheel like gear teeth. This prevents the track from slipping under load. The Ninjaflex is almost too flexible, allowing the tracks to stretch and almost climb off the wheels, so [James] plans to experiment with some other materials in the future. The chassis consists of two 2020 T-slot extrusions, which allows convenient mounting of the wheel bogies and other components.

The interlocking track pieces

For initial driving tests [James] fitted two completely overpowered 1500 W brushless motors that he had on hand, which he plans to replace with smaller geared DC motors at a later stage.

A standard RC system is used for control, but it does not offer a simple way to control a skid steer vehicle. To solve this, [James] added an Arduino between the RC receiver and the motor ESC. It converts the PWM throttle and turn signal from the transmitter, and combines is into differential PWM outputs for the two ESCs.

Continue reading “Modular Rover Platform Rolls On 3D Printed Flexible Tank Tracks” →

Autonomous Rover Navigates The House With LIDAR

September 22, 2020 by 1 Comment

For those wishing to explore robot autonomy, there’s no better way then to learn by doing. [Greg] was in that camp, and decided to build an autonomous rover to roam his house, and learned plenty along the way.

[Greg]’s aims with the project were to build a robot that was capable of navigating his home without external assistance. To do the job, a Raspberry Pi 3 was put in charge, and kitted out with a LIDAR for mapping. Pololu Roboclaw motor controllers are then used to allow the Raspberry Pi to drive the robot’s individual wheel motors, giving the four-wheeled bot skid steering capability.

[Greg] goes into immense detail on the project’s writeup, exploring the code and concepts behind its autonomous abilities. Creating a robot that can navigate using LIDAR is no easy task, but [Greg] does a great job of explaining how it all works, and why.

It’s not the first autonomous rover we’ve seen here, and we’re sure it won’t be the last. If you’ve got your own build coming together in the lab, be sure to let us know. Video after the break.

Continue reading “Autonomous Rover Navigates The House With LIDAR” →

ExoMy Is A Miniature European Mars Rover With A Friendly Face

September 5, 2020 by 5 Comments

Over the past few weeks, a new season of Mars fever kicked off with launches of three interplanetary missions. And since there’s a sizable overlap between fans of spaceflight and those of electronics and 3D printing, the European Space Agency released the ExoMy rover for those who want to experience a little bit of Mars from home.

ExoMy’s smiling face and cartoonish proportions are an adaptation of ESA’s Rosalind Franklin (formerly the ExoMars) rover which, if 2020 hadn’t turned out to be 2020, would have been on its way to Mars as well. While Rosalind Franklin must wait for the next Mars launch window, we can launch ExoMy missions to our homes now. Like the real ESA rover, ExoMy has a triple bogie suspension design distinctly different from the rocker-bogie design used by NASA JPL’s rover family. Steering all six wheels rather than just four, ExoMy has maneuvering chops visible in a short Instagram video clip (also embedded after the break).

ExoMy’s quoted price of admission is in the range of 250-500€. Perusing instructions posted on GitHub, we see an electronics nervous system built around a Raspberry Pi. Its published software stack is configured for human remote control, but as it is already running ROS (Robot Operating System), it should be an easy on-ramp for ExoMars builders with the ambition of adding autonomy.

ExoMy joins the ranks of open source rover designs available to hackers with 3D printing, electronics, and software skills. We recently covered a much larger rover project modeled after Curiosity. Two years ago NASA JPL released an open source rover of their own targeting educators, inspiring this writer’s own Sawppy rover project, which is in turn just one of many projects tagged “Rover” on Hackaday.io. Hackers love rovers!