Using CNC to machine the electronics plate for Mars Rover

Using CNC to machine the electronics plate for Mars Rover

Here we are using our homemade CNC to machine a custom electronics plate for the new Mars Rover we’re building. The robot’s circuit boards and electronic components are mounted onto this plate, which is then mounted inside the robot’s main box. Check out the video and the photos below.

The completed electronics plate for the Mars Rover.

Here is the electronics plate with the various circuit boards and other electronic components mounted. Wiring and soldering comes next. The wires will go through the rectangular holes underneath each circuit board and then run beneath the plate.

Machining CNC parts for the telegraph

Machining CNC parts for the telegraph

Today, we worked on the wireless telegraph project. We decided to mount the electronics on brass and copper plates, so we designed the parts on the CAD system and then machined the parts on our home made CNC mill (one of our many projects over the last year). Using the CNC to make project parts was a really cool use of what has become our favorite tool. Here are some pics of the CNC.

Here is our CNC mill just after machining the copper telegraph base plate. Top left: the computer and electronics box we built. Top center: Cooling tower for the water-cooled spindle. Top right: The 3-phase Variable Frequency Drive (VFD), which powers the 24,000 rpm spindle, is mounted on the wall. Mounted on the wall just below the computer box: an LCD panel for the CNC user interface. Right hand side: The stepper-motor-driven CNC machinery, which is made out of steel and aluminum. You can see the copper part on the blue riser (which is machinable wax).  Front center: the system’s keyboard, the emergency stop button box we built, and the jog box (for moving the CNC manually).

 

A close up of the copper base plate just after it has been machine by the CNC.

 

Camille showing off her new copper base plate, fresh out of the CNC

We needed two of the base plates (one for each side of the telegraph system), so we machined the second one out of brass instead of copper (using the same CNC file).

Here Camille assembles the telegraph electronics onto the baseplate

Here are the electronics for the telegraph system mounted on the copper plate. The electronics shown here include an Arduino Nano in a screw terminal board, a 7.4v Lithium Polymer Battery, an Xbee Radio, a potentiometer (for tuning the voltage to the Telegraph Sounder), and a small speaker). This copper plate will be mounted inside the base of the telegraph system.

 

 

 

Working on wireless telegraph

Working on wireless telegraph

Here at Beatty Robotics, we have a keen interest in mixing cool, old technology with exciting new technology. Recently, we became interested in Morse Code and telegraph equipment. We began exchanging written secret messages in Morse Code. And then we continued on by learning to tap the codes with rocks and listen to them at some distance. We are still learning and practicing, but it’s pretty clear that they are getting better and better and will soon be fluent. So now we’ve embarked on our next project, which is to build a functioning telegraph system by refurbishing several very old, antique telegraph keys and sounders, and then combining then with our modern electronics knowledge. We aren’t ready to show the completed project quite yet, but here are some pics of us wiring up the electronics. As we complete the project over the next few weeks, we’ll post pictures of the complete telegraph system (we’re hoping it’s going to look pretty cool), an explanation of how it all works, and the list of components.

Genevieve solders the headers on the Arduino Nano while I wire up the screw terminal board

I power up our wireless Xbee LCD screen to see if test messages are being transmitted properly from the Telegraph key. (The telegraph system itself won’t include an LCD screen. This was just for a test.)

Working together on some delicate soldering on the main microcontroller

See the finished product here: Wireless Telegraph

Terrabot

Terrabot

Today, we would like to introduce Terrabot, our Terrain Traveling Robot. Based on a modified “rock crawler” chassis, its primary purpose is to traverse rocks, branches, steep slopes, flower beds, boulders, mountain trails, and other extremely rough terrain.

Terrabot

Terrabot is equipped with 4-wheel steering (4WS). Two high torque servos shift machined aluminum linkages to rotate its front and back wheels independently. Note the navigation GPS on top of the back servo (on the left) and the sensor turret on the front (right). Terrabot’s four wheels are driven by two powerful brushless motors (bright blue) and robust gearboxes (centered in each axle).

Terrabot’s highly-articulated chassis is designed to twist up to 90 degrees as the robot is moving, allowing it to climb over huge boulders and other obstacles. In this picture, the chassis is articulated 45 degrees. Note that the back tires are still on the ground because the center linkages of the bot are twisted.

Terrabot’s topside electronics include a tiny Arduino Nano (lower left), an XBee Radio (right), and a 9-DOF Mongoose Inerntial Measurement Unit (IMU). The IMU measures the degree of tilt and the rate of acceleration in the X, Y, Z planes, which we plan to use for our stabilization algorithm.

Terrabot’s other electronics are stuffed into the little chamber inside the aluminum core (note the blue LED at the bottom of the picture). This includes the two Electronic Speed Controllers for the motors, the Pololu Maeastro motor/servo controller, the power rails, various voltage regulators, and other electronics. The navigation GPS (see the first picture), is mounted on top of the rear servo so that it has a clear view of the sky.

Terrabot Side View, showing the shocks, the frame, and LIPO battery beneath. Note the “roll posts” we installed on the top to protect the topside electronics if Terrabot falls off a rock during a climb and flips over. (We learned this one from experience!)

Terrabot Front View. There are three sonars mounted in the sensor turret, which rotates 270 degrees when the robot “looks around” to determine the best course through obstacle-ridden rough terrain.

Black Dragon

Black Dragon

Today, we would like to introduce Black Dragon, our newest flying robot quadrotor. This newest flyer incorporates everything we’ve learned to date about ease-of-use, modular maintainability, crash resistance, lightness, and safety. While we constructed all our previous full-sized quadrotors with aluminum, we designed and built this new flyer with super-cool carbon fiber material. This particular type of carbon fiber, which carries the brand-name “Dragon Plate” (www.dragonplate.com), is used in the aerospace and defense industry, among others. It’s very light, very strong, looks fantastic (the photos don’t do it justice), and is surprisingly machinable.

BLACK DRAGON: Our first carbon fiber quadrotor

Our CAD drawing for the Black Dragon frame design

 

Our Carbon Fiber Frame

Carbon Fiber Arm. Note that we drilled the motor holes and landing gear holes directly into the arm in order to reduce parts

Like our previous quadrotors, we are using the Arduino-based ArduPilot Mega board as the main controller, a 3-axis Inertial Measurement Unit shield (IMU), a GPS for autopilot navigation, Magnetometer for heading control, and a Sonar for altitude control. The robot can be flown via an RC controller or on various autopilot modes. New features include a large illuminated toggle switch for easy on/off in the field, large main plates to hold electronics and wires, improved frame design, complete elimination of the motor mounts (which used to be susceptible to bending), an x-oriented frame (as opposed to +) to provide an open field of view for a camera mounted on the the front, and improved landing gear.

The carbon fiber material is excellent. We love it. It’s easier to machine and work with than we expected (even with the necessary safety precautions), it’s very attractive, but best of all it’s both very light and very strong. For example, the previous aluminum arms weighed in at about 50 grams each. The new arms are 21 grams each. The whole unit ways in at about 850 grams without the LIPO battery.

Close up view of some of Black Dragon’s electronics

We’ve loaded the software into the microcontroller, calibrated the ESC/motors, double-checked the prop rotation, tested the sonar, set the magnetic declination on the magnetometer, confirmed the GPS is giving good long/lat, and it’s ready to fly. We’ve flown it a few inches off the floor indoors just to make sure it’s good-to-go and so far it seems excellent. Perhaps our best ever. As soon as the rain stops, we’ll be testing it in the big blue sky.

For more details on our various flying drone robots, go here.

I want to give special thanks to the folks at Dragon Plate for sending us their cool material.