Mechanical Broncos

for Open Simulator

From Ocean Engineering by Kayaker Magic. Last updated June 2020


  • Mechanical Bronco with Control Panel
  • Locked or anyone can control
  • Rotates on three axes
  • Turn spin off for easier riding
  • Timed mode using mouse-look-mode
  • Shows top 3 scores
  • Five auto program buttons
  • Manual joystick mode
  • NC for changing skill parameters
  • Very low LI, low vertex count
  • COPY, MOD, NOtrans
Links to other parts of this document:
These are Mechanical Bucking Broncos for OpenSimulator. You are posed to sit on a bucking bronco. A control panel has auto program buttons for very slow (sexy) to very fast (cowboy) bucking action. The bronco rotates on three axes, bucking forward and backward, rolling back and forth and spinning left and right. The spinning motion can be turned off to make the ride easier. In manual mode you can control the bronco with a “joystick”. Clicking and dragging your mouse on the joystick area makes the bronco move. The control panel can be locked so that only the owner is allowed to use it, or unlocked so that anyone can control it. A parameter note-card in inventory allows you to change the skill level, the maximum angles of travel, the position of the avatar on the seat and several other settings.

There is a timer and a scoreboard for measuring who can stay on the bronco the longest! To test your skill, go into mouse-look while it is bucking and see how long you can keep your cursor above the bronco’s head.

There are several different Mechanical Bronco designs, each with different features:

The Mechanical Bronco version has the neck and head of a horse that moves smoothly as the horse bucks. When no-one is riding, the Bronco tosses its head, flicks its ears and tries to graze on the AstroTurf.

Pictures of other bucking broncos that are available can be found below. As of this writing there is a shark and an R2D2 version.

Using the Control Panel

Click one of the 5 auto program buttons to start the bronco going. The SPIN/NOSPIN button turns spin off in auto modes to make the ride more difficult or easier. The STOP button will stop the bronco immediately and put it back in “fidget” mode. AUTO is just an indicator of what mode was used last. Clicking and dragging on the joystick area will move the bronco in manual mode. Dragging the mouse up and down on this area will buck the bronco forward and backward. Dragging the mouse left and right will roll, spin or do both to the bronco. The ROLL/SPIN button selects between these three options. The timer display is a stopwatch that shows how long the current rider has been in mouse-look. The CLEAR button resets the top three scores on the score panel. Clicking on the HELP button sends you to this WEB page, so I guess you already figured that out! Clicking on the Ocean Engineering logo will take you to my blog with links to demos and other products of mine.

Timed Rides on the Mechanical Broncos

For a timed ride:
  • Go into mouse-look mode while riding and bucking
  • track the head of the bronco with your cursor
  • your time ends when the head and cursor are too far apart.
The Bronco will time how long you can stay on the ride, but some skill is required. The timer starts when you go into mouse-look mode while in one of the auto programs or while someone drives the bronco in manual mode with the joystick area of the control panel. To stay on the bronco, you must hold your cursor close to the head of the bronco. Actually, you should aim at a point a meter or so above the head. If the bronco bucks or turns away from your cursor faster than you can follow, you will be bucked off and your time ends. The top 3 scores are displayed on the contest panel.

The angle between the head and cursor must remain below 100 degrees for you to stay on the bronco. This skill setting can be changed in the parameter NC. Some of the bronco versions (horse, Velociraptor, ichthyosaur) have a floating text display above the head that shows you your current angle. The viewer occasionally gets “gymbol locked” and cannot mouse-look to some angles! If this happens, it is the luck of the ride and you will probably get bucked off. You can decrease the likelihood of this happening by using the manual joystick to rotate the bronco to face towards the control panel.

OpenSim is quite perverse and will usually mount you facing backwards when you go into mouse-look mode. This will usually get you bucked off in the first second. One way to solve this is to sit on the bronco before starting auto or manual bucking, rotate the view until you are facing forward, then have a friend start the bronco going. By yourself, you can go in and out of mouse-look mode several times until you are facing forward in mouse-look and can see the console when not. Click on one of the auto mode buttons then immediately go into mouse-look mode one last time.

Getting into Mouse-Look-Mode

Mouse-look-mode is notoriously difficult to get into! Pressing the ‘m’ key is supposed to do this, but the local chat box often catches all characters you type. To stop this you have to click on empty ground or click one of the arrows on the Move Controls dialog first. The Camera Controls dialog has a button that puts you in mouse-look-mode. On mice that have a scroll wheel, zooming into the back of your avatars head can put you in mouse-look-mode. But this also fails to work depending on what you were looking at last! Tapping the left and right arrows before zooming usually fixes that.

Using a Bronco in a Contest

If you want to have a bucking bronco contest, you probably should lock the control panel to prevent cheating. Then the owner of the bronco can set the mode the same for each contestant. I also recommend using manual mode to rotate the bronco to the same starting angle for each contestant. To avoid the startup problems with mouse-look mode, stop the bronco before they get on, have them adjust their mouse-look angle, tell you when they are ready, and then hit the auto program mode to start them bucking. Note that their timer does not start until two things happen: They are in mouse-look AND the bronco is bucking. This can happen in either order but it is usually easier for the contestants to sit and get into mouse-look first, then start them bucking.

Changing Default Parameters

The bucking bronco has a note-card in inventory for setting the skill level and other parameters. I had to make the whole Bronco MOD so that you can edit this NC! But I do not recommend that you actually change anything. Moving any of the prims will probably cause the bucking animation to fail! This NC is named “.params” and will look something like this:
skillangle=100;     //hold your cursor this close to head to stay on (degrees)
touchtime=0.11;     //skip touch events that come in faster than this
timestep=0.1;       //how fast the bronco animates
sitpos=<0.44,0.15,1.95>;   //position of the avatar (rotation is calculated dynamically)
soundvol=0.3;       //volume of the sounds made while fidgeting
buckmag=45.0;       //maximum buck angle back and forth in degrees, +/-
tiltmag=30.0;           //maximum tilt angle left and right in degrees
spinmag=100;        //maximum spin angle left and right degrees

You can probably figure this out from reading the comments, but here is a little more discussion of each parameter:
skillangle How close (in degrees, your cursor must stay to the head of the bronco. (Actually a point a meter or so above the head). This angle must be fairly large or it is too hard for anyone to stay on the bronco.
touchtimeDragging on the joystick area with your mouse can generate a lot of events that lag your experience. To cut down on this you can set this number larger, but eventually the movement of the bronco will become too jerky.
timestepHow fast the bronco is animated, in seconds. A value of 0.1 (a tenth of a second) means 10 times a second. This is probably as fast as most grids will let scripts update things. Even if your grid runs certain events faster, that would make even SLOW mode too fast. Best to leave this alone.
sitposThis parameter allows you to change the position where the avatar sits. This is a vector and the co-ordinate system is … interesting. There is help from the script and below to set this up.
soundvolWhen the bronco has nothing to do it fidgets and makes noise. This could potentially be annoying so you can set the volume low with this parameter. Values range from 0.0 (off) to 1.0 (full volume). No, you cannot set it to 11.
buckmagThe bronco rotates 45 degrees up and 45 degrees down by default when bucking in auto mode. You can change this with the buckmag parameter, but setting it too large will make the bronco rotate unnaturally into the support pillar.
tiltmagThe bronco tilts 30 degrees back and forth while bucking. Change this with the tiltmag (tilt magnitude) parameter. Setting it too large will look non-physical.
spinmagThe bronco spins 100 degrees left and 100 degrees right by default when bucking in auto mode. You can change that here, but setting spinmag to more than 180 degrees will rotate more than all the way around. Note that manual mode has its own maximum magnitude limits that you cannot change here.

Adjusting the Sit Position

You can sit on the bronco, open the .params note-card and edit the sitpos to help set it up for your avatar. Every time you save the NC back into inventory, the sitting avatars position will be updated to match. Changing the X component of sitpos (the first value) will move the avatar forward and backward. Modifying the Y component (second value) will move the avatar left and right. The third value moves the avatar up and down. (All movements relative to the current orientation of the bronco). Change the sitpos values one at a time and save the NC to see the effect it has on a sitting avatar. You can embed the avatar a little into the bronco, that makes it look like a cushy seat. Try to get the avatars right fist close to the rope loop, but this will never be correct for all the different sizes and types of avatars out there.

Other Versions of Mechanical Brocos

I have ideas for even more designs! What bronco do you think I should make next?

The Bucking Shark version is a fun mechanical bronco that looks like a shark! I saw one like this in RL and since my company name is Ocean Engineering, I had to make one with a water theme! When no-one is riding, the shark plays sound clips from a popular shark movie.

The Bucking R2D2 version of the mechanical bronco looks like the popular ‘droid. I made this one for people who have Science Fiction themed venues. When no-one is riding, he talks in ‘droid speak. When you sit on him, he makes a rude noise before trying to buck you off.

To learn about other products from Ocean Engineering, click here.