by Mark (Moonyoung) Lee & Kevin J. Wang:
What is seeing without feeling? The field of Virtual Reality has recently been gaining much attention, with the Oculus Rift and Google Cardboard paving the path of visualizing a world that is not physically there. But what if the virtual reality experience could be enhanced by incorporating tactile sensing? The Haptic Glove we developed accomplishes just that – without seeing the physical structure of the object, you will still be able to feel the presence of virtual objects.
The goal of the project is to create an exoskeleton on the forearm arm that provides tactile perception for the user. The volume of the virtual object will be emulated based on the intensity of a light source that is placed inside a black box. Depending on the relative brightness of the source to the phototransistors that are mounted onto the exoskeleton, a distance between the user’s hand and the light source can be determined. By varying the brightness of the LED light source, the size of the virtual object will vary. To provide the tactile perception, servos mounted on the exoskeleton provides a pulling force, preventing the user’s fingers from reaching closer to the light source. In addition to the resistive force that act against the fingers’ movement, there are also flat surfaces at the tips of the exoskeleton that will flip up to make contact with the user’s fingers, which actually provides the sense of touching a real object.
Feeling the light in a whole new way - [Link]
by w2aew @ youtube.com:
This video shows a simple circuit that can be used to control the position of an typical remote control (RC) style servo with an analog voltage. The PWM (pulse width modulated) control signal format for an RC servo is reviewed, followed by the presentation of a simple circuit that can be used to control the servo with a simple adjustable DC voltage. The circuit is built with rail-to-rail op amps and a few resistors and capacitors. Note that the schematic presented doesn’t include all of the decoupling on the power supply and reference lines that you would likely want to include. A description of the circuit, as well as a more in depth discussion of each of the building blocks such as an integrator, hysteresis comparator and DC signal conditioner circuit including an attenuator, inverting amplifier and level shifter, is presented.
Circuit Fun: Control an RC Servo with an adjustable DC voltage - [Link]
Ondřej Karas of DoItWireless writes:
We described simple method, how to drive modellers servo. Today, we are going to try to drive this servo from potentiometer connected to TR module ADC. It is reaction to forum thread where is discussion about airplane model control possibility.
Wireless servo controller II - [Link]
This easy-to-build PWM generator project uses the ATtiny45 processor and can be used as a tester for servos. It operates at 5V and can drive maximum PWM load of 1A. [via]
PWM generator and servo tester using ATtiny45 - [Link]
The Arachnoid Mobile Platform is an open source robotics development platform used to make small autonomous moving robots. It can be either configured as a four-legged robot, or as a two wheeled robot. The PCB board holds all the electronics and mechanical components, and also serves as the chassis of the robot.
AMP – Arachnoid Mobile Platform - [Link]
Ray Wang writes:
Hi, I recently built a reflow toaster oven using an Arduino. I know it’s pretty standard stuff, but my version has an automatic oven door opener (using a servo) and circulation fan to speed up the cooling time, and remote notification using an RF transmitter
Reflow toaster oven using an Arduino - [Link]
Gadget Gangster @ instructables.com writes:
A little bigger than a postage stamp, the Simple Servo Tester lets you control two digital or analog servos without using a transmitter or receiver, just plug in your battery pack to start testing.
Use it to check your servos before installing them into your models or to center your servos when setting up linkages. The Simple Servo Tester can also be tuned to precisely center your servos – Some manufactures consider 1.520 milliseconds to be center while others use 1.500 milliseconds.
Simple Servo Tester - [Link]
Trandi made this simple DIY Servo tester based on ATTiny85:
I had to test a RC speed controller that I wanted to use to control an electric car window motor, and for the 100th time I was facing the same dilemma: find 8 batteries for my remote control, dismount the RX part from the quadcopter and use that, OR grab the Arduino and write quickly some code to generate the corresponding signals? Neither of which was actually particularly handy… So I finally decided to build a small stand alone servo tester.
DIY servo tester based on ATTiny85 - [Link]
soldersplash.co.uk folks are creating a 24 channel Servo controller. It’s controllable over SPI or USB and can be stacked on top of our SplashBase board to enable network control. Up to 5 of these can be used to enable control of 120 servos in total.
24 Channel Servo Controller- [Link]
Since we’ve been busy adding quite a few I2C sensors and breakouts lately, I thought this technical overview of the 2-wire “Inter-Integrated Circuit” bus might be handy. I2C isn’t fast (typically limited to 400kHz in most real-world situations), but it’s convenient since it only requires two pins and more than 120 devices can be connected on the same bus, address space permitting. For low-pin count devices, it can be a real life-saver since you can hook an OLED display, a DAC, a 7-segment display and 16 servo motors up to your Arduino with a measley two pins and some careful coding! The full bus specification is available from NXP in UM10204 – the bus was created by Philips, whose semiconductor branch later became NXP — but the more concise information from Embedded Systems Academy might be easier to digest as a starting point. The FAQ has some very good information in it.
I2C Bus Technical Overview - [Link]