hauptmech
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What is a CIM motor?
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CCL Industrial Motors according to this thread. So CIM is an acronym for the manufacturer of one of the motors the FIRST guys use. The term seems to have been generalized in that community to mean a ...

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How is Topology-based representation invariant to certain change in environment
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2 votes

The concept you might be missing is homeomorphism. The donut=coffee cup visual example at that link might help. Of all the ways you can change the environment (move the obstacles) there is a subset of ...

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Remaking an RC transmitter for controlling aircraft
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If you are looking at automatic control, consider using a radio modem instead of RC transmitter/receiver. One example. These are often used on hobby drones for relaying telemetry and control via ...

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How to make a robot arm follow a shape/path
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The image you post is one way that should work. In the image, $\tau$ is the joint torques, and $x_d(t)$, $\dot{x}_d(t)$, and $\ddot{x}_d(t)$ are the Cartesian shape trajectory. You mention "whole ...

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simulation of robots
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For visualization and kinematics, Gazebo works fine. You can use C++ or Python to work with it. There is lots of integration with ROS as well if you like that sort of thing. If you want a clean and ...

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How to interrupt on a data ready trigger when communications to the sensor are interrupt driven?
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2 votes

I think you have a false assumption somewhere. A very quick scan through the atmel datasheet and arduino twi.c does not show any problems. Why do you think the microcontroller can't handle the ...

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Syncing camera with other signals
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2 votes

Cameras that support syncing will probably do so via an external signal. Google "genlock" or "timecode sync" or "external trigger" to get started. For instance, here's a link to external trigger ...

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How to combine odometry information with time-shifted information from IMU?
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You're robot must be moving pretty fast for this delay to cause problems. Use a circular buffer to store the odometry readings, so you'll have a record of the last 100ms of odometry readings. Use ...

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How do I create a portable solar panel lipo charger?
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Make sure you understand Lithium Ion battery safety before proceeding. Lithium Ion batteries have limits on charging current and charging voltage. The typical charging technique is to provide the ...

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DC motor shaft and gear installation
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The term I'd use for cog-bar and cog is rack and pinion. Plastic pinions are usually press-fit if they are very small or use set screws if they are just small. I assume you are asking the question ...

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Mechanical robustness/shock resistance LiPo batteries
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as @Chuck points out, LiPo cell are sensitive to thermal runaway triggered by mechanical rupture or deformation. An example of a manufactures shock spec can be found here. (They test for a drop onto ...

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ROS and Kinect data without callbacks
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Until you learn more about ROS the best approach is to use a callback. You can copy the data to a global variable and use that in your main program if it helps you reason about the data flow better. ...

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How can I measure the actual speed and distance traveled of the robot with an external setup?
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There are a couple good options depending on the scale of your project for capturing a ground truth. For large scale outside (cars or agricultural vehicles) RTK GPS can be had for a very reasonable ...

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How mature is real-time programming in robotics?
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If you actually need real-time, then you use a real-time operating system. Safety monitoring, data acquisition, and constant sample rate control loops are common subsystems that use real-time ...

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Having trouble getting correct homogeneous transformation matrices for my robotic arm
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1 votes

A quick partial answer to help move you forward: 1) Your axis are labeled for a left-handed coordinate system. Use right-handed (swap the x and y axis in your diagram) 2) There is no prismatic ...

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How timer interrupt is handled in the presence of other interrupt services?
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1 votes

No. The actual time is calculated from counter registers that automatically increment. The timer interrupt will be delayed, and things the timer interrupt is triggering will be delayed. This is called ...

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Calculate ticks with three encoders?
1 votes

To measure position more accurately you need to use all three. They are used for choosing which motor phase to energise, which is called commutation. Searching for "6 step commutation" will give you ...

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Do I have to use the CAN protocol that the motor controller uses in order to communicate with it?
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1 votes

CANopen is a application level protocol and socketcan is at the transport level. You can send Canopen messages using socketcan without any problems. You can compose canopen messages by hand but it ...

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How to get the accurancy of the position system?
1 votes

The amount of rotation that the motor is capable of depends on the physical design of the motor. Usually the motor is combined with a transmission (eg gears) of some kind which also influence how far ...

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Which sensors can be used to feel breeze blowing by the robot?
1 votes

Microphone chips have been used as a transducer for this due to their low cost. (This being high density pressure measurements)

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Denavit-Hartenberg convention in practice
1 votes

CAD is used as a first estimate. Often the kinematics (coordinate frames) are part of the design specification, and you can use those numbers directly. Where they are not, all mechanical design CAD ...

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What knowledge should I have if I want to establish a robotics company?
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If having a company is more important to you than working in robotics for someone else, business skills and people skills are more important than technical skills. Being successful requires ...

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The reason(s)/benefit(s) to use realtime operating system instead of while-loop on MCU
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Using an RTOS on a microcontroller is for reducing the complexity of developing your solution, and reduces the need for programmer expertise for device drivers, at cost of increasing the complexity of ...

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Ontology/marketplace of robotics components and integration environment (BPEL or CAD for robotics)?
1 votes

Do professional robot designers use semi or fully automated toolchains to implement physical systems? Of course. Especially if you broaden your definition of robot to electro-mechanical system. ...

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What do the model numbers in Harmonic Drive gear drives represent?
1 votes

It is the pitch diameter of the flex spline in inches/10. You can see it used it their equations for thrust force on the wave generator.

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Real time implementation of EtherCAT master with ros_control
1 votes

You would confuse or mislead people if you called a non-realtime system with realtime subsystems a realtime system. If your motor control is realtime, just say that. That you have realtime control of ...

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Relation between Power, Weight & Speed
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The calculations are difficult. Here are some foundation equations. If you demonstrate interest and refine your question based on what you learn I'm sure that myself or someone else will help you ...

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finding the frequency of CAN send and CAN receive messages using CAN in Ubuntu
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candump can output the timestamp for each message in different formats. Check the usage notes of candump. candump -t d can0 will give you the time difference between messages for instance.

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How do robotics companies track faults in production systems?
1 votes

Company size and market expectations shape the specific tools used. Almost always kept confidential to some degree. Issue tracking, remote diagnosis (and device security), and stochastic monitoring ...

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Rotary Serial Elastic Actuator
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1 votes

For an arm with series elastic actuators I'm not aware of an open source design. There are many mechanisms you can find in research papers if you search for them. For force control you have a few ...

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