Six Wheels (En)rolling: Mars Rovers Going To School

August 3, 2018 by Roger Cheng 7 Comments

Few things build excitement like going to space. It captures the imagination of young and old alike. Teachers love to leverage the latest space news to raise interest in their students, and space agencies are happy to provide resources to help. The latest in a long line of educator resources released by NASA is an Open Source Rover designed at Jet Propulsion Laboratory.

JPL is the birthplace of Mars rovers Sojourner, Spirit, Opportunity, and Curiosity. They’ve been researching robotic explorers for decades, so it’s no surprise they have many rovers running around. The open source rover’s direct predecessor is ROV-E, whose construction process closely followed procedures for engineering space flight hardware. This gave a team of early career engineers experience in the process before they built equipment destined for space. In addition to learning various roles within a team, they also learned to work with JPL resources like submitting orders to the machine shop to make ROV-E parts.

ROV-E

ROV-E Team

Once completed, ROV-E became a fixture at JPL public events and occasionally visits nearby schools as part of educational outreach programs. And inevitably a teacher at the school would ask “The kids love ROV-E! Can we make our own rover?” Since most schools don’t have 5-axis CNC machines or autoclaves to cure carbon fiber composites, the answer used to be “No.”

Until now.

Continue reading “Six Wheels (En)rolling: Mars Rovers Going To School” →

Robot Rovers Of The Early Space Race

July 29, 2018 by Jenny List 3 Comments

In the early 1970s, the American space program was at a high point, having placed astronauts upon the surface of the moon while their Soviet competitors had not taken them beyond an Earth orbit. It is however a simplistic view to take this as meaning that NASA had the lead in all aspects of space exploration, because while Russians had not walked the surface of our satellite they had achieved a less glamorous feat of lunar exploration that the Americans had not. The first Lunokhod wheeled rover had reached the lunar surface and explored it under the control of earth-bound engineers in the closing months of 1970, and while the rovers driven by Apollo astronauts had placed American treadmarks in the lunar soil and been reproduced on newspaper front pages and television screens worldwide, they had yet to match the Soviet achievements with respect to autonomy and remote control.

At NASA’s Jet Propulsion Laboratory there was a project to develop technology for future American rovers under the leadership of [Dr. Ewald Heer], and we have a fascinating insight into it thanks to the reminiscences of [Mike Blackstone], then a junior engineer.

The aim of the project was to demonstrate the feasibility of a rover exploring a planetary surface, picking up, and examining rocks. Lest you imagine a billion dollar budget for gleaming rover prototypes, it’s fair to say that this was to be achieved with considerably more modest means. The rover was a repurposed unit that had previously been used for remote handling of hazardous chemicals, and the project’s computer was an extremely obsolete DEC PDP-1.

We are treated to an in-depth description of the rover and its somewhat arcane control system. Sadly we have no pictures save for his sketches as the whole piece rests upon his recollections, but it sounds an interesting machine in its own right. Heavily armoured against chemical explosions, its two roughly-humanoid arms were operated entirely by chains similar to bicycle chains, with all motors resting in its shoulders. A vision system was added in the form of a pair of video cameras on motorised mounts, these could be aimed at an object using a set of crosshairs on each of their monitors, and their angles read off manually by the operator from the controls. These readings could then be entered into the PDP-1, upon which the software written by [Mike] could calculate the position of an object, calculate the required arm positions to retrieve it, and command the rover to perform the required actions.

The program was a success, producing a film for evaluation by the NASA bigwigs. If it still exists it would be fascinating to see it, perhaps our commenters may know where it might be found. Meanwhile if the current JPL research on rovers interests you, you might find this 2017 Hackaday Superconference talk to be of interest.

Thanks [JRD] for the tip.

Flexible PCB Becomes The Actuator

July 29, 2018 by Jenny List 13 Comments

An electromagnetic coil gun takes a line of electromagnets working together to form a moving electromagnetic field. These fields accelerate a project and boom, you have electricity moving matter, often at an impressive rate of speed.

[Carl Bugeja] has taken the idea and in a sense turned it upon its head with his flexible PCB actuator. Now the line of electromagnets are the moving part and the magnetic object the stationary one. There is still a line of flat PCB inductors in the classic coil gun configuration, but as the title suggests on a flexible substrate.

The result is a curiously organic motion reminiscent of some lizards, caterpillars, or snakes. It can move over the magnet in a loop, or flex in the air above it. It’s a novel moving part, and he’s treated us to a video which we’ve placed below the break.

He has plans to put it to use in some form of robot, though while it certainly has promise we’d be interested to know both what force it can produce and whether flexible PCB is robust enough for repeated operation. We salute him for taking a simple idea and so effectively proving the concept.

We’ve brought you [Carl]’s work before, most notably with his PCB motor.

Continue reading “Flexible PCB Becomes The Actuator” →

Couch Potato Refined: Self-Rotating TV Uses Plywood Gears

July 26, 2018 by Al Williams 20 Comments

When we first saw [Mikeasaurus’] project to rotate his TV 90 degrees in case he wanted to lay down and channel surf we were ready to be unimpressed. But it grew on us as we read about how he fabricated his own gearing system to make a car seat motor rotate the TV.

The gearing system is made from plywood and the design was from geargenerator.com, a freebie design tool we’ve covered before. You’d think you’d need a laser cutter, but in this case, the gear forms were printed out, glued on the plywood and then cut out manually. Each gear is made of several laminated together.

Continue reading “Couch Potato Refined: Self-Rotating TV Uses Plywood Gears” →

Juggling Machine Listens To The Bounce To Keep Ball In The Air

July 25, 2018 by Dan Maloney 10 Comments

It’s a seemingly simple task: bounce a ping-pong ball on a wooden paddle. So simple that almost anyone can pick up a ball and a paddle and make a reasonable job of it. Now, close your eyes and try to do it just by the sound the ball makes when it hits the paddle. That’s a little tougher, but this stepper-driven platform juggler manages it with aplomb.

That’s not to say that the path to the finished product in the video below was a smooth one for [tkuhn]. He went through multiple iterations over the last two years, including a version that surrounded the juggling platform with a fence of phototransistors to track where the ball was at any time. That drove four stepper motors through a cross-linkage that popped the platform up at just the right moment to keep the ball moving, and at just the right angle to nudge it back toward the center of the platform. The current version of the platform does away with the optical sensors in favor of four small microphones. The mics pick up the sharp, well-defined sound of the ball hitting the platform, process the signal through an analog circuit, and use that signal to trigger a flip-flop if the signal exceeds a setpoint. An Arduino then measures the time delay between arriving signals, calculates the ball’s position on the platform, and drives the steppers through a PID loop to issue the corrective bounce.

The video below is entrancing, but we found ourselves wishing for a side view of the action too. It’s an impressive build nonetheless, one that reminds us of the many maze-runner and Stewart platform robots we’ve seen.

Continue reading “Juggling Machine Listens To The Bounce To Keep Ball In The Air” →

An Integrated Electromagnetic Lifting Module For Robots

July 25, 2018 by Donald Papp 7 Comments

The usual way a robot moves an object is by grabbing it with a gripper or using suction, but [Mile] believes that electromagnets offer a lot of advantages that are worth exploring, and has designed the ELM (Electromagnetic Lifting Module) in order to make experimenting with electromagnetic effectors more accessible. The ELM is much more than just a breakout board for an electromagnet; [Mile] has put a lot of work into making a module that is easy to interface with and use. ELM integrates a proximity sensor, power management, and LED lighting as well as 3D models for vertical or horizontal mounting. Early tests show that 220 mW are required to lift a 1 kg load, but it may be possible to manage power more efficiently by dynamically adjusting drive voltage depending on the actual load.

[Mile]’s focus on creating an easy to use, integrated solution that can be implemented easily by others is wonderful to see, and makes the ELM a great entry for The Hackaday Prize.

Was The Self Driving Car Invented In The 1980s?

July 25, 2018 by Al Williams 29 Comments

The news is full of self-driving cars and while there is some bad news, most of it is pretty positive. It seems a foregone conclusion that it is just a matter of time before calling for an Uber doesn’t involve another person. But according to a recent article, [Ernst Dickmanns] — a German aerospace engineer — built three autonomous vehicles starting in 1986 and culminating with on-the-road demonstrations in 1994 for Daimler.

It is hard to imagine what had to take place to get a self-driving car in 1986. The article asserts that you need computer analysis of video at 10 frames a second minimum. In the 1980s doing a single frame in 10 minutes was considered an accomplishment. [Dickmanns’] vehicles borrowed tricks from how humans drive. They focused on a small area at any one moment and tried to ignore things that were not relevant.

Continue reading “Was The Self Driving Car Invented In The 1980s?” →